On May 28, 9:49*am, Home Guy wrote:
George wrote:
I have to waste more time explaining why I want to do something or
why I want certain information about measurement techniques, and
instead I get a bunch of arm-chair blow-hardts that think they
know better.

Poor you

No. *Poor usenet. *

Poor every future poster to any newsgroup that asks a simple technical
question and gets told by the peanut gallery that it's important to know
all the ancilliary circumstances surrounding the question when in
reality in the end those circumstances have no bearing on the question
or it's answer.

@Home Guy:

It is a poor craftsman that blames the tools...

Ask a question based in this reality (rather than your fantasy which
is filled with gaps in your practical knowledge that someone could
drive a box truck through) and you can get an answer...

Ask a fishy question that doesn't sound right to people who *do*
know, and they will want to know more about the situation before
they chime in with their opinion...

You very poorly defined your "issue" to begin with and then you
focused on techno-babble and ill-advised methods to attempt
to monitor your power usage... When there are devices that
are purpose made and could be bought and installed in any
panel whose power consumption you wish to monitor...

~~ Evan

On May 28, 11:14*am, Home Guy wrote:
mike used improper usenet message composition style by unnecessarily
full-quoting:

You're pushing a very big rock up a hill to nowhere.

I should not see a huge spike in monthly usage during a month when our
hvac usage is practically zero. *Investigating the reasons for this
spike is not path to nowhere.

Your meter will give you little useful information.

An unnecessarily dramatic statement.

To say that a clamp-on amp meter can't give useful information is
hyperbole.

You need to KNOW the phase.

To the extent that my aggregate power factor is less than .95 or .9,
yes, then I need to know the phase.

Are you suggesting that my effective power factor is likely to be less
than .9?

What is the power factor of 10 to 20 year-old florescent lamp ballasts?
Or a 1 hp, 220 VAC fan motor? *Or a 10 year old refridgerator? *Or a
typical desktop PC power supply?

Those are the largest (and probably only) non-resistive loads in
question here.

Why do you care?

Because I pay the bills. *What a stupid ass question that was.

If you think the equipment is faulty, you should enlist the power
company.

I've already stated that I've contacted them, and that I expect to
encounter difficulty in having them ever admit that their metering
equipment could be faulty or even undertake a process to evaluate the
meter, but I will pursue every course of action and give them every
chance to determine that.

I've found 'em to be very knowledgeable and helpful.

In the pages and pages of materials and contracts that exist for this
utility, describing all manner of service obligation and liability,
billing, etc, I find nothing in print that defines a process whereby a
billing meter is tested or what is done if a meter is found to be
defective.

There is absolutely nothing I can find in writing even contemplating the
possibility of a meter that does not measure correctly. *

I believe that issue is a political "hot potatoe" for all municipal
electricity suppliers, something they'd rather not have to deal with and
hence they largely remain silent about it.

If you think they're intentionally screwing you,

I believe that they never "intentionally" screw anyone, but that instead
they put up a front that their meters are always correct, all the time,
and reinforce that by not mentioning the possibility of erroneous meter
operation anywhere in any printed material they make available, let
alone define in writing a process or methods to test a meter that the
client believes is suspect.

Measuring VA is an exercise in futility.

The worst I can do by measuring VA is to OVER-ESTIMATE my watts used by
5 or 10% - unless you think it's likely that my aggregate power factor
is less than 90%.

Your "finger" ain't gonna hold up in court anyway.

Making my own measurements would be a first-step. *I never said I'd use
those measurement in court (that is your hyperbole again).

If indeed it got that far, then I would investigate my options have
having an acredited third-party measurement performed, and that would
only happen if my local utility did not perform their own tests that I
was satisfied was unbiased and accurate.

@Home Guy:

Ah, the true picture emerges -- an accounts payable rep who thinks
that because they pay the bills they understand how everything
works...

You clearly lack the technical expertise to do anything about this
on YOUR side of the meter...

You seem to not understand the regulations which protect consumers
and control how power is sold in your state -- therefore you are
unaware
of your potential remedies in this "situation" if one really exists...

Instead of spending your time researching something actually useful
which might shed some light on what is actually going on (if anything
really is at all) you have chosen to ask stupid questions which are
clearly not on the proper wavelength to make any sense to someone
who actually understands electrical issues AND you are chasing after
something *YOU* can do which would support *YOUR* claim that
your electrical meter is not functioning correctly when there may
in fact be a procedure to follow which has already been defined by
the public utilities commission (or equivalent in your state) which
would almost always involve bringing in an uninterested third
party with the proper credentials and equipment to assess what
if anything is happening in this whole convoluted story...

It seems whenever you get some sound advise that would make
sense in the real world, you attack the contributor because the
person didn't respond with the specific answer you were looking
for in your especially preferred format... So you critique based
on newsgroup etiquette and posting format rather than the
supplied content -- keep doing that and you will be properly
labeled as a troll and written off as such...

~~ Evan

On May 28, 12:03*pm, bob haller wrote:
Just for the heck of it go after hours and turn off your main breaker
with friends watching building.

I had a customewr at a local shopping mall they had electrical
troubles and found a connection from their meter powering public
spaces in the mall, seemingly left over from the malls construction in
the 60s. Tenants on that meter had been paying a big chunk of the
malls electric bill..

This was identified one night when the customer had a fire. The fire
department pulled the meter blacking out a big piece of the mall.

The mall claimed no knowledge I believe there was a lawsuit,,,,,,

@bob haller:

That doesn't sound like it was a professionally managed "mall"...

Sounds more like it was being run by people like Home Guy...

All the malls I have seen inside of have entirely separate
switchgear to power tenant versus house circuits...

~~ Evan

On May 28, 9:03*am, Home Guy wrote:
Smitty Two wrote:
Something seems a tad fishy, but I don't think sampling some
current readings is going to help sort it out.

It's a start.

400 amps of 3-phase is a lot of juice to run a few computers,
lights, and soldering irons.

The main disconnect switch before the meter is name-plate rated at 400
amps. *It doesn't mean we're going to ever draw that much.

OP needs to spend less time fantasizing about how many hours are
in a month and more time inventorying the equipment in the building

I know exactly what equipment is in the building - I work there.

talking to its occupants

I talk to them every day. *

and looking for wires running off across the parking
lot to a secret garage lab that glows in the dark.

What-ever.

Another example of a usenet post that starts with a question, and
devolves into "why are you asking?".

I have to waste more time explaining why I want to do something or why I
want certain information about measurement techniques, and instead I get
a bunch of arm-chair blow-hardts that think they know better.

@Home Guy:

You are the one being the UseNet douche here guy...

Commercial electricity is metered based on peak demand
I don't care where you are in the US, it is the way federal
laws on the buying and selling of energy are written...

That first given established, you totally blew off the source
of the *most* qualified electrical advice on this newsgroup
supplied by RBM because you didn't like the 'format' of
his posting method and so called 'etiquette' violations
when your postings actual content is way out in orbit
of some other planet...

Now let us address the specific issues you seem to
be experiencing:

-- Your electrical meter is locked within a cabinet
enclosure where *you* the consumer are unable
to observe the cumulative readings on it at various
points during the billing period to determine any
abnormal usage issues...

That is *highly* abnormal for a meter to be locked
inside a cabinet like that where the indicator of
the amount of electricity you are going to be billed
for is concealed from you... I would place a call
to the local public utilities official and explain your
situation and that your meter is hidden away from
you where you can not read it but once a month
when the power company unlocks its cabinet,
that install does not sound kosher -- at the very
least an observation hole can be made in the
cabinet so you can see your meter...

-- Is there only *one* tenant in this "building"
as it sounds like there is only one meter...
That is an abnormal way to pay for electricity
in a commercial building if there are multiple
tenants irregardless of whether the lease
terms are gross or net (NN) (NNN)...

With one meter all you would be able to do
legally without some sort of sub-metering
involved (the emon demon that RBM mentioned)
is divide the total cost by the square footage
of the building and apportion it to the tenants
based on the tenant's square footage...

-- You are so caught up in the minutiae of how
you can home brew a way to calculate your
power use by simply calculating all the wattage
of all the devices and appliances used in your
occupancy that you seem blissfully unaware
that many things require a "starting current"
like your furnace motor and the ballasts for
those exterior light fixtures on the mechanical
timer -- with a commercial electrical service you
get billed for the highest simultaneous demand
for current as well as the simple kWh of usage...

It sounds to me like you have a lot to learn before you
even attempt to dispute anything with anyone...

It is also waaaay to late to dispute charges for
electricity billed like over a year ago -- there is usually
a time limitation which covers when you can challenge
a utility bill, I have never heard of one that let you go
more than 60-90 days after the billing date to initiate
a complaint...

Good luck man -- hope you can return safely to
earth since you are clearly in orbit somewhere with
all of this...

~~ Evan

On Sat, 28 May 2011 09:40:47 -0400, Home Guy wrote:

" wrote:

An amp meter measures amps, not watts. Even if you assume 120V,
you're still calculating volt-amps, not watts.

A volt-amp is a watt, when the load is resistive.

That's a *BIG* assumption.

If I perform high-speed sampling of both the voltage and current, and if
I multiply each reading together to get VA for each sample, and if
integrate those VA samples over time, I will get the actual watts or KWh
that I should be billed for. That would correctly take into account
reative / inductive loads (like motors, light ballasts, computer power
supplies, etc).

Yes, or you could just use the kWH meter the power company gave you.

If I simply calculate watts as equal to VA based on the current
measurement from a clamp-on meter, then I'm over-estimating what the
billing meter is "seeing" because I'd be assuming that all my loads are
resistive. In other words, my calculation of watts = VA can't help but
assume that current and voltage are in phase with each other.

That's what everyone has been telling you, yes. Did you actually read any of
this thread?

The billing meter knows how to calculate wattage correctly when the
current and voltage is out of phase.

....and it ignores harmonics. It's a smart little thing.

I guess a clamp-on amp meter that also had a couple of voltage probes so
that it could simultaneously measure the voltage could measure true
wattage would be needed.

Nope. You're still reading VA, not watts.

The errors you mention above will likely be even bigger, though
Surprisingly, a watt-hour meter (it's already there) is the real
way to measure watt-hours. ;-)

As long as the watt-hour meter is working correctly.

Have them calibrate it (they're replace it with one that is calibrated).

Which seems highly suspect given all the info I've been posting here.

Maybe *you* suspect it. They're really pretty good.

On Sat, 28 May 2011 09:03:21 -0700 (PDT), bob haller wrote:

Just for the heck of it go after hours and turn off your main breaker
with friends watching building.

I had a customewr at a local shopping mall they had electrical
troubles and found a connection from their meter powering public
spaces in the mall, seemingly left over from the malls construction in
the 60s. Tenants on that meter had been paying a big chunk of the
malls electric bill..

This was identified one night when the customer had a fire. The fire
department pulled the meter blacking out a big piece of the mall.

The mall claimed no knowledge I believe there was a lawsuit,,,,,,

They can often get a limited refund from the power company, who will then add
it back into the mall's bill. If not, a suit is certainly in order.

"RBM" wrote in :


"Mark" wrote in message
...
On May 27, 8:47 pm, Home Guy wrote:
RBM used improper usenet message composition style by full-quoting:

3) There are (on average) 30.4 days in a month, and therefore 730
hours in a month. If I take the above wattage calculation (120 x
total_current) and multiply it by 730, then divide by 1000, I
should get a quantity energy measurement (KWh) that should match
(or approximate) my bill from the local utility - assuming that
the load in use at the time of the readings are representative of
daily or continuous use. If this method of obtaining a
representative monthly KWh measurement is not correct (or needs
more refinement) then please state what, why or how.

**You're not going to be the least bit accurate trying to calculate
that way.

I want to establish several use-case situations, primarily a
"worst-case" KWh monthly usage by assuming that all the devices that are
normally on during a week-day 9-am to 5-pm work day and turned off at
all other times are instead left on continuously 24/7.

I can also get current readings for other use-case situations (evenings
and week-ends) that should give me a more closer-to-reality current
reading and factor in their time-of use over the course of a month.

This is a small office - not a home. There are fewer variable involved.

There is no reason that you shouldn't be able to look at the
electric meter.

The meter is in a locked cabinet. The only time I get to see it is when
the meter-reader guy comes around once a month to read it.

I suspect the meter is in a locked cabinet to prevent tampering / bypass
(the meter is inside the utility / furnace room of the building and is
not accessible from the outside).

And besides, having the ability to lay my eyes on the meter won't tell
me anything about the accuracy of the meter, or the real-time current
consumption.

All I want to know is - should the current readings from a clamp-on
meter (when extrapolated across the 730 hours of a typical month) jive
with the accumulated KWh reading as measured by a typical billing
meter? Do I have to do any "special" math to the wattage I calculate
with the meter to arrive at what the billing meter is measuring?

yes you are correct you can get a rough reading this way..
you need to measure and sum only the 3 black cables, do not include
the white striped cable in the sum.

Add up the 3 currents and multiply by 120 and this is your VAs and the
actual Watts will be equal to or less then the VAs.

Multiply by hours and you have Watt Hours.

Divide by 1000 and you have kWh which is how you are billed.

Mark


This is a commercial service and metering equipment. How is he going to
guestimate demand?




since the white return wire returns the current from all 3 phases,wouldn't
that give you the sum of all the currents?
Perhaps a more accurate measurement of total power than the other way.


--
Jim Yanik
jyanik
at
localnet
dot com

On May 28, 4:21*pm, Jim Yanik wrote:
"RBM" wrote :







"Mark" wrote in message
....
On May 27, 8:47 pm, Home Guy wrote:
RBM used improper usenet message composition style by full-quoting:

3) There are (on average) 30.4 days in a month, and therefore 730
hours in a month. If I take the above wattage calculation (120 x
total_current) and multiply it by 730, then divide by 1000, I
should get a quantity energy measurement (KWh) that should match
(or approximate) my bill from the local utility - assuming that
the load in use at the time of the readings are representative of
daily or continuous use. If this method of obtaining a
representative monthly KWh measurement is not correct (or needs
more refinement) then please state what, why or how.

**You're not going to be the least bit accurate trying to calculate
that way.

I want to establish several use-case situations, primarily a
"worst-case" KWh monthly usage by assuming that all the devices that are
normally on during a week-day 9-am to 5-pm work day and turned off at
all other times are instead left on continuously 24/7.

I can also get current readings for other use-case situations (evenings
and week-ends) that should give me a more closer-to-reality current
reading and factor in their time-of use over the course of a month.

This is a small office - not a home. There are fewer variable involved..

There is no reason that you shouldn't be able to look at the
electric meter.

The meter is in a locked cabinet. The only time I get to see it is when
the meter-reader guy comes around once a month to read it.

I suspect the meter is in a locked cabinet to prevent tampering / bypass
(the meter is inside the utility / furnace room of the building and is
not accessible from the outside).

And besides, having the ability to lay my eyes on the meter won't tell
me anything about the accuracy of the meter, or the real-time current
consumption.

All I want to know is - should the current readings from a clamp-on
meter (when extrapolated across the 730 hours of a typical month) jive
with the accumulated KWh reading as measured by a typical billing
meter? Do I have to do any "special" math to the wattage I calculate
with the meter to arrive at what the billing meter is measuring?

yes you are correct you can get a rough reading this way..
you need to measure and sum only the 3 black cables, do not include
the white striped cable in the sum.

Add up the 3 currents and multiply by 120 and this is your VAs and the
actual Watts will be equal to or less then the VAs.

Multiply by hours and you have Watt Hours.

Divide by 1000 and you have kWh which is how you are billed.

Mark

This is a commercial service and metering equipment. How is he going to
guestimate demand?

since the white return wire returns the current from all 3 phases,wouldn't
that give you the sum of all the currents?
Perhaps a more accurate measurement of total power than the other way.

--
Jim Yanik
jyanik
at
localnet
dot com- Hide quoted text -

- Show quoted text -

It would seem to me that if the one white return wire returned
the current from all 3 phases it would have to be one hell
of a conductor.

"Jim Yanik" wrote in message
4...
"RBM" wrote in :


"Mark" wrote in message
...
On May 27, 8:47 pm, Home Guy wrote:
RBM used improper usenet message composition style by full-quoting:

3) There are (on average) 30.4 days in a month, and therefore 730
hours in a month. If I take the above wattage calculation (120 x
total_current) and multiply it by 730, then divide by 1000, I
should get a quantity energy measurement (KWh) that should match
(or approximate) my bill from the local utility - assuming that
the load in use at the time of the readings are representative of
daily or continuous use. If this method of obtaining a
representative monthly KWh measurement is not correct (or needs
more refinement) then please state what, why or how.

**You're not going to be the least bit accurate trying to calculate
that way.

I want to establish several use-case situations, primarily a
"worst-case" KWh monthly usage by assuming that all the devices that are
normally on during a week-day 9-am to 5-pm work day and turned off at
all other times are instead left on continuously 24/7.

I can also get current readings for other use-case situations (evenings
and week-ends) that should give me a more closer-to-reality current
reading and factor in their time-of use over the course of a month.

This is a small office - not a home. There are fewer variable involved.

There is no reason that you shouldn't be able to look at the
electric meter.

The meter is in a locked cabinet. The only time I get to see it is when
the meter-reader guy comes around once a month to read it.

I suspect the meter is in a locked cabinet to prevent tampering / bypass
(the meter is inside the utility / furnace room of the building and is
not accessible from the outside).

And besides, having the ability to lay my eyes on the meter won't tell
me anything about the accuracy of the meter, or the real-time current
consumption.

All I want to know is - should the current readings from a clamp-on
meter (when extrapolated across the 730 hours of a typical month) jive
with the accumulated KWh reading as measured by a typical billing
meter? Do I have to do any "special" math to the wattage I calculate
with the meter to arrive at what the billing meter is measuring?

yes you are correct you can get a rough reading this way..
you need to measure and sum only the 3 black cables, do not include
the white striped cable in the sum.

Add up the 3 currents and multiply by 120 and this is your VAs and the
actual Watts will be equal to or less then the VAs.

Multiply by hours and you have Watt Hours.

Divide by 1000 and you have kWh which is how you are billed.

Mark


This is a commercial service and metering equipment. How is he going to
guestimate demand?




since the white return wire returns the current from all 3 phases,wouldn't
that give you the sum of all the currents?
Perhaps a more accurate measurement of total power than the other way.


--
Jim Yanik
jyanik
at
localnet
dot com

No, the neutral only carries the imbalanced load, which is why it is allowed
to be smaller than the ungrounded legs

On May 28, 4:21*pm, Jim Yanik wrote:
"RBM" wrote :





"Mark" wrote in message
....
On May 27, 8:47 pm, Home Guy wrote:
RBM used improper usenet message composition style by full-quoting:

3) There are (on average) 30.4 days in a month, and therefore 730
hours in a month. If I take the above wattage calculation (120 x
total_current) and multiply it by 730, then divide by 1000, I
should get a quantity energy measurement (KWh) that should match
(or approximate) my bill from the local utility - assuming that
the load in use at the time of the readings are representative of
daily or continuous use. If this method of obtaining a
representative monthly KWh measurement is not correct (or needs
more refinement) then please state what, why or how.

**You're not going to be the least bit accurate trying to calculate
that way.

I want to establish several use-case situations, primarily a
"worst-case" KWh monthly usage by assuming that all the devices that are
normally on during a week-day 9-am to 5-pm work day and turned off at
all other times are instead left on continuously 24/7.

I can also get current readings for other use-case situations (evenings
and week-ends) that should give me a more closer-to-reality current
reading and factor in their time-of use over the course of a month.

This is a small office - not a home. There are fewer variable involved..

There is no reason that you shouldn't be able to look at the
electric meter.

The meter is in a locked cabinet. The only time I get to see it is when
the meter-reader guy comes around once a month to read it.

I suspect the meter is in a locked cabinet to prevent tampering / bypass
(the meter is inside the utility / furnace room of the building and is
not accessible from the outside).

And besides, having the ability to lay my eyes on the meter won't tell
me anything about the accuracy of the meter, or the real-time current
consumption.

All I want to know is - should the current readings from a clamp-on
meter (when extrapolated across the 730 hours of a typical month) jive
with the accumulated KWh reading as measured by a typical billing
meter? Do I have to do any "special" math to the wattage I calculate
with the meter to arrive at what the billing meter is measuring?

yes you are correct you can get a rough reading this way..
you need to measure and sum only the 3 black cables, do not include
the white striped cable in the sum.

Add up the 3 currents and multiply by 120 and this is your VAs and the
actual Watts will be equal to or less then the VAs.

Multiply by hours and you have Watt Hours.

Divide by 1000 and you have kWh which is how you are billed.

Mark

This is a commercial service and metering equipment. How is he going to
guestimate demand?

since the white return wire returns the current from all 3 phases,wouldn't
that give you the sum of all the currents?

no the white wire returns only the UNBALANCED current

I agree the OP should gain access to the real meter so he can read the
meter say once a day and find out what is going on.

Mark

"Home Guy" wrote in message ...
RBM used improper if not deplorable usenet message composition style by
full-quoting:

This is a commercial service and metering equipment. How is he
going to guestimate demand?

Demand (or load) doesn't have to be guestimated.

Do you have a demand meter?
Do you know what a demand meter is?
Typically commercial meters register peak demand and that peak demand figure
is used as a multiplier

On Sat, 28 May 2011 15:21:47 -0500, Jim Yanik wrote:

"RBM" wrote in :


"Mark" wrote in message
...
On May 27, 8:47 pm, Home Guy wrote:
RBM used improper usenet message composition style by full-quoting:

3) There are (on average) 30.4 days in a month, and therefore 730
hours in a month. If I take the above wattage calculation (120 x
total_current) and multiply it by 730, then divide by 1000, I
should get a quantity energy measurement (KWh) that should match
(or approximate) my bill from the local utility - assuming that
the load in use at the time of the readings are representative of
daily or continuous use. If this method of obtaining a
representative monthly KWh measurement is not correct (or needs
more refinement) then please state what, why or how.

**You're not going to be the least bit accurate trying to calculate
that way.

I want to establish several use-case situations, primarily a
"worst-case" KWh monthly usage by assuming that all the devices that are
normally on during a week-day 9-am to 5-pm work day and turned off at
all other times are instead left on continuously 24/7.

I can also get current readings for other use-case situations (evenings
and week-ends) that should give me a more closer-to-reality current
reading and factor in their time-of use over the course of a month.

This is a small office - not a home. There are fewer variable involved.

There is no reason that you shouldn't be able to look at the
electric meter.

The meter is in a locked cabinet. The only time I get to see it is when
the meter-reader guy comes around once a month to read it.

I suspect the meter is in a locked cabinet to prevent tampering / bypass
(the meter is inside the utility / furnace room of the building and is
not accessible from the outside).

And besides, having the ability to lay my eyes on the meter won't tell
me anything about the accuracy of the meter, or the real-time current
consumption.

All I want to know is - should the current readings from a clamp-on
meter (when extrapolated across the 730 hours of a typical month) jive
with the accumulated KWh reading as measured by a typical billing
meter? Do I have to do any "special" math to the wattage I calculate
with the meter to arrive at what the billing meter is measuring?

yes you are correct you can get a rough reading this way..
you need to measure and sum only the 3 black cables, do not include
the white striped cable in the sum.

Add up the 3 currents and multiply by 120 and this is your VAs and the
actual Watts will be equal to or less then the VAs.

Multiply by hours and you have Watt Hours.

Divide by 1000 and you have kWh which is how you are billed.

Mark


This is a commercial service and metering equipment. How is he going to
guestimate demand?




since the white return wire returns the current from all 3 phases,wouldn't
that give you the sum of all the currents?

Only the *difference* of the three phases is returned in the neutral. With a
balanced load there will be zero current in the neutral.

Perhaps a more accurate measurement of total power than the other way.

RBM wrote:

Do you have a demand meter?

I have no idea. I would think that most utility companies try to
communicate as infrequently and as minimally as possible with their
customers.

We bought this building 6 years ago. What-ever meter it had is
what-ever meter it had. When we wanted the lights to come on, we placed
a call to the local utility and at some point soon after the lights came
on.

They don't seem to be in the habbit of sending a welcome basket along
with a nice, comprehensive information package telling us what choices
of meters and electrical service we have, nor a copy of the
NIST-traceable certification for the meter.

Do you know what a demand meter is?

Never heard of it.

Typically commercial meters register peak demand and that peak
demand figure is used as a multiplier

What would be the criteria for determining when a "demand meter" is
installed in a given premises, vs a non "demand-meter" ?

Does a "demand meter" give a more accurate measure of energy
consumption?

On 5/28/2011 9:26 PM, Home Guy wrote:
....

Does a "demand meter" give a more accurate measure of energy
consumption?

It's the tariff schedule. Call the business office or look at the bill;
it'll tell you what your rate(s) are.

It's not unusual as others have said for commercial to be on such a
tariff but it's more generally so for manufacturing than simply office
but it'll all depend on where you are.

As somebody else has noted, there will be very specific rules in the
state in which you're located regarding what the utility is required to
do regarding a question regarding billing. Look at that information
that is bound to be available from your state rate commission or
whatever the equivalent is called where you are.

Messing around as you're doing isn't going to get you anywhere at all
useful.

Have you evn verified that the meter is actually physically read on a
monthly basis rather than estimated and the balloon "reading" isn't
simply the annual catchup when they finally do read it? As mentioned
before that would certainly be one possible explanation.

--

On May 28, 9:21*pm, Jim Yanik wrote:
"RBM" wrote :







"Mark" wrote in message
....
On May 27, 8:47 pm, Home Guy wrote:
RBM used improper usenet message composition style by full-quoting:

3) There are (on average) 30.4 days in a month, and therefore 730
hours in a month. If I take the above wattage calculation (120 x
total_current) and multiply it by 730, then divide by 1000, I
should get a quantity energy measurement (KWh) that should match
(or approximate) my bill from the local utility - assuming that
the load in use at the time of the readings are representative of
daily or continuous use. If this method of obtaining a
representative monthly KWh measurement is not correct (or needs
more refinement) then please state what, why or how.

**You're not going to be the least bit accurate trying to calculate
that way.

I want to establish several use-case situations, primarily a
"worst-case" KWh monthly usage by assuming that all the devices that are
normally on during a week-day 9-am to 5-pm work day and turned off at
all other times are instead left on continuously 24/7.

I can also get current readings for other use-case situations (evenings
and week-ends) that should give me a more closer-to-reality current
reading and factor in their time-of use over the course of a month.

This is a small office - not a home. There are fewer variable involved..

There is no reason that you shouldn't be able to look at the
electric meter.

The meter is in a locked cabinet. The only time I get to see it is when
the meter-reader guy comes around once a month to read it.

I suspect the meter is in a locked cabinet to prevent tampering / bypass
(the meter is inside the utility / furnace room of the building and is
not accessible from the outside).

And besides, having the ability to lay my eyes on the meter won't tell
me anything about the accuracy of the meter, or the real-time current
consumption.

All I want to know is - should the current readings from a clamp-on
meter (when extrapolated across the 730 hours of a typical month) jive
with the accumulated KWh reading as measured by a typical billing
meter? Do I have to do any "special" math to the wattage I calculate
with the meter to arrive at what the billing meter is measuring?

yes you are correct you can get a rough reading this way..
you need to measure and sum only the 3 black cables, do not include
the white striped cable in the sum.

Add up the 3 currents and multiply by 120 and this is your VAs and the
actual Watts will be equal to or less then the VAs.

Multiply by hours and you have Watt Hours.

Divide by 1000 and you have kWh which is how you are billed.

Mark

This is a commercial service and metering equipment. How is he going to
guestimate demand?

since the white return wire returns the current from all 3 phases,wouldn't
that give you the sum of all the currents?
Perhaps a more accurate measurement of total power than the other way.

--
Jim Yanik
jyanik
at
localnet
dot com- Hide quoted text -

- Show quoted text -

Don't you know anything? If all three phases had the same
current,there would be zero current in the neutral.

On May 29, 3:26*am, Home Guy wrote:
RBM wrote:
Do you have a demand meter?

I have no idea. *I would think that most utility companies try to
communicate as infrequently and as minimally as possible with their
customers.

We bought this building 6 years ago. *What-ever meter it had is
what-ever meter it had. *When we wanted the lights to come on, we placed
a call to the local utility and at some point soon after the lights came
on. *

They don't seem to be in the habbit of sending a welcome basket along
with a nice, comprehensive information package telling us what choices
of meters and electrical service we have, nor a copy of the
NIST-traceable certification for the meter.

Do you know what a demand meter is?

Never heard of it.

Typically commercial meters register peak demand and that peak
demand figure is used as a multiplier

What would be the criteria for determining when a "demand meter" is
installed in a given premises, vs a non "demand-meter" ?

Does a "demand meter" give a more accurate measure of energy
consumption?
It only shows the maximum. Usually they only show peaks that last a
fewminutes
The purpose of a demand meter is to discourage the electric consumer
from high peaks in demand. Usually there is an additional charge that
depends on this peak.
The reason for this is the cable and generating capacity has to be
sized to the peak.

On May 28, 10:26*pm, Home Guy wrote:

What would be the criteria for determining when a "demand meter" is
installed in a given premises, vs a non "demand-meter" ?

Does a "demand meter" give a more accurate measure of energy
consumption?

@Home Guy:

A "demand meter" comes into play as a factor when:

-- The size of the electrical service is exceeds a certain
predetermined size...

-- The property is zoned commercial/industrial usually
will have a demand meter unless you are a small tenant
with a separate meter and your electrical service capacity
is smaller than the predetermined size mentioned above...

A "demand meter" is no more or less accurate than the
meter you have installed on your house -- it is simply
keeping track of an additional aspect to your power use,
rather than only being an odometer counting how many
kWh of energy you are using in a month, it is also keeping
track of what your greatest simultaneous draw of energy
(a.k.a. your "peak demand") was during the billing period
which like others have said acts as a multiplier or
determines which billing rate you will be charged for your
electric bill for that month...

With a "demand meter" service, a business which uses
a consistent 20KW of electrical energy during a billing
period would pay a different rate than a customer who
uses 100KW of electrical energy in short bursts even
if the overall consumption of kWh during said billing
period was identical...

~~ Evan

On May 29, 3:54*am, Evan wrote:
On May 28, 10:26*pm, Home Guy wrote:



What would be the criteria for determining when a "demand meter" is
installed in a given premises, vs a non "demand-meter" ?

Does a "demand meter" give a more accurate measure of energy
consumption?

@Home Guy:

A "demand meter" comes into play as a factor when:

-- The size of the electrical service is exceeds a certain
predetermined size...

-- The property is zoned commercial/industrial usually
will have a demand meter unless you are a small tenant
with a separate meter and your electrical service capacity
is smaller than the predetermined size mentioned above...

A "demand meter" is no more or less accurate than the
meter you have installed on your house -- it is simply
keeping track of an additional aspect to your power use,
rather than only being an odometer counting how many
kWh of energy you are using in a month, it is also keeping
track of what your greatest simultaneous draw of energy
(a.k.a. your "peak demand") was during the billing period
which like others have said acts as a multiplier or
determines which billing rate you will be charged for your
electric bill for that month...

With a "demand meter" service, a business which uses
a consistent 20KW of electrical energy during a billing
period would pay a different rate than a customer who
uses 100KW of electrical energy in short bursts even
if the overall consumption of kWh during said billing
period was identical...

~~ Evan

EVANGELIST, NOW WHY DO YOU WANT TO COMPLICATE THE OPs LIFE WITH THAT
KIND OF INFO?
A BETTER WAY FOR A HOME OWNER / CONSUMER TO ESTIMATE HIS COST IS TO
MONITOR HIS USAGE VS HIS COST ON A MONTH TO MONTH BASIS.....IF HE MISSE
$ BY A FEW DIGIT$ ITS NOT THE END OF THE WORLD AND THE LESSON IN
OVERUSE IS A GOOD ONE TO MAKE AMENDS AND APPLY SAVING
MEASURES...WHETHER IT MAY BE FIRING AN UNSCRUPULOUS ENERGY WASTING
EMPLOYEE OR CHANGING TO MORE ENERGY EFFICIENT EQUIPMENT OR CURBING USE
TO MEET ONES FISCAL BUDGET.


WHY BOTHER WITH CALCULATIONS IF YOU ARE GONNA SCREW IT UP ANYWAY ;-)

PAT ECUM
TGITM

On 5/28/2011 9:49 AM, Home Guy wrote:
George wrote:

I have to waste more time explaining why I want to do something or
why I want certain information about measurement techniques, and
instead I get a bunch of arm-chair blow-hardts that think they
know better.

Poor you

No. Poor usenet.

Not at all. If you walked into a room and presented your "novel" ideas
to folks who have a clue and understand what could be done and why your
ideas make very little practical sense they would respond in the same
fashion asking "why" in order to discover if there was something you
didn't convey or to offer a better idea.



Poor every future poster to any newsgroup that asks a simple technical
question and gets told by the peanut gallery that it's important to know
all the ancilliary circumstances surrounding the question when in
reality in the end those circumstances have no bearing on the question
or it's answer.

See above.

Home Guy wrote:
mike used improper usenet message composition style by unnecessarily
full-quoting:

You're pushing a very big rock up a hill to nowhere.

I should not see a huge spike in monthly usage during a month when our
hvac usage is practically zero. Investigating the reasons for this
spike is not path to nowhere.

Investigating is good. The method you're using is the rock
to nowhere.
Get a tool that can do the job...and he works for the power company.


Your meter will give you little useful information.

An unnecessarily dramatic statement.

To say that a clamp-on amp meter can't give useful information is
hyperbole.

You need to KNOW the phase.

To the extent that my aggregate power factor is less than .95 or .9,
yes, then I need to know the phase.

Are you suggesting that my effective power factor is likely to be less
than .9?

Yes, I am.
If you have a bunch of CFL lights and nothing else running, your
aggregate PF can be 0.6.
During the day, when the lights are off and motors are running, it
might be 0.6 in the other direction. The power meter only cares about
what's happening NOW.
There's a lot of legislation in place or on the way to make NEW
stuff do internal power factor correction. But it's gonna take a while
to make a difference.
Power factor is a mythical number that assumes that voltage and current
are both perfect sine waves that are out of phase.
Take a look at the load from your computer. You might find that
it's a bunch of narrow spikes that bear no resemblance to sine waves.
A "kill a watt" meter will give you a power factor number, but the
crest factor may be WAY bigger than 1.

The only number that makes ANY difference is the one after the $ on your
bill.

Quit messing around and get the power company out to look at it.
Show them the evidence you're bitching about here. Only they can
do anything about it.


What is the power factor of 10 to 20 year-old florescent lamp ballasts?
Or a 1 hp, 220 VAC fan motor? Or a 10 year old refridgerator? Or a
typical desktop PC power supply?

Those are the largest (and probably only) non-resistive loads in
question here.

Why do you care?

Because I pay the bills. What a stupid ass question that was.

If you think the equipment is faulty, you should enlist the power
company.

I've already stated that I've contacted them, and that I expect to
encounter difficulty in having them ever admit that their metering
equipment could be faulty or even undertake a process to evaluate the
meter, but I will pursue every course of action and give them every
chance to determine that.

I've found 'em to be very knowledgeable and helpful.

In the pages and pages of materials and contracts that exist for this
utility, describing all manner of service obligation and liability,
billing, etc, I find nothing in print that defines a process whereby a
billing meter is tested or what is done if a meter is found to be
defective.

There is absolutely nothing I can find in writing even contemplating the
possibility of a meter that does not measure correctly.

What's on the paper is inconsequential until you get into a court of law.
Fret over that when it happens.
CALL THE POWER COMPANY...you don't appear to have the skills or
equipment to make a challenge.


I believe that issue is a political "hot potatoe" for all municipal
electricity suppliers, something they'd rather not have to deal with and
hence they largely remain silent about it.

If you think they're intentionally screwing you,

I believe that they never "intentionally" screw anyone, but that instead
they put up a front that their meters are always correct, all the time,
and reinforce that by not mentioning the possibility of erroneous meter
operation anywhere in any printed material they make available, let
alone define in writing a process or methods to test a meter that the
client believes is suspect.

Measuring VA is an exercise in futility.

The worst I can do by measuring VA is to OVER-ESTIMATE my watts used by
5 or 10% - unless you think it's likely that my aggregate power factor
is less than 90%.

Your "finger" ain't gonna hold up in court anyway.

Making my own measurements would be a first-step. I never said I'd use
those measurement in court (that is your hyperbole again).

It's my assertion that GETTING THE POWER COMPANY TO INVESTIGATE
is the first step.
The second step is to call whatever agency regulates the power company.
Attempting to measure it yourself is way down the list. You ain't got the
equipment to prove 'em wrong.

If indeed it got that far, then I would investigate my options have
having an acredited third-party measurement performed, and that would
only happen if my local utility did not perform their own tests that I
was satisfied was unbiased and accurate.

On 5/28/2011 4:21 PM, Jim Yanik wrote:
wrote in :


wrote in message
...
On May 27, 8:47 pm, Home wrote:
RBM used improper usenet message composition style by full-quoting:

3) There are (on average) 30.4 days in a month, and therefore 730
hours in a month. If I take the above wattage calculation (120 x
total_current) and multiply it by 730, then divide by 1000, I
should get a quantity energy measurement (KWh) that should match
(or approximate) my bill from the local utility - assuming that
the load in use at the time of the readings are representative of
daily or continuous use. If this method of obtaining a
representative monthly KWh measurement is not correct (or needs
more refinement) then please state what, why or how.

**You're not going to be the least bit accurate trying to calculate
that way.

I want to establish several use-case situations, primarily a
"worst-case" KWh monthly usage by assuming that all the devices that are
normally on during a week-day 9-am to 5-pm work day and turned off at
all other times are instead left on continuously 24/7.

I can also get current readings for other use-case situations (evenings
and week-ends) that should give me a more closer-to-reality current
reading and factor in their time-of use over the course of a month.

This is a small office - not a home. There are fewer variable involved.

There is no reason that you shouldn't be able to look at the
electric meter.

The meter is in a locked cabinet. The only time I get to see it is when
the meter-reader guy comes around once a month to read it.

I suspect the meter is in a locked cabinet to prevent tampering / bypass
(the meter is inside the utility / furnace room of the building and is
not accessible from the outside).

And besides, having the ability to lay my eyes on the meter won't tell
me anything about the accuracy of the meter, or the real-time current
consumption.

All I want to know is - should the current readings from a clamp-on
meter (when extrapolated across the 730 hours of a typical month) jive
with the accumulated KWh reading as measured by a typical billing
meter? Do I have to do any "special" math to the wattage I calculate
with the meter to arrive at what the billing meter is measuring?

yes you are correct you can get a rough reading this way..
you need to measure and sum only the 3 black cables, do not include
the white striped cable in the sum.

Add up the 3 currents and multiply by 120 and this is your VAs and the
actual Watts will be equal to or less then the VAs.

Multiply by hours and you have Watt Hours.

Divide by 1000 and you have kWh which is how you are billed.

Mark


This is a commercial service and metering equipment. How is he going to
guestimate demand?




since the white return wire returns the current from all 3 phases,wouldn't
that give you the sum of all the currents?
Perhaps a more accurate measurement of total power than the other way.


The neutral only returns unbalanced current.

Here's a question no one has asked. Why is the meter
in a box that is locked? I've never seen this before.
Do you know if similar meters are all locked? Why
not ask the electric company to leave the box unlocked?
That way at least you could see what the actual meter
is doing.

harry wrote:

Does a "demand meter" give a more accurate measure of energy
consumption?

(I note that no explicit answer is given for that question)

It only shows the maximum. Usually they only show peaks that
last a few minutes
The purpose of a demand meter is to discourage the electric
consumer from high peaks in demand. Usually there is an
additional charge that depends on this peak.

So are you saying that customers with "demand meters" are billed on the
basis of their peak demand - a reading based on only a few minutes worth
of energy usage as seen over an entire billing period?

How is that a fair or equitable way to bill a customer?

Are commercial customers that typically use between 2000 and 3000 kwh of
electricity per month normally considered as candidates for a demand
meter, or are they used for much higher usage customers?

" wrote:

Here's a question no one has asked. Why is the meter
in a box that is locked? I've never seen this before.

That question was posed earlier in this thread, and I speculated as to
the reason for a locked cabinet in a post I made on Friday night (8:47
pm est):

============
The meter is in a locked cabinet. The only time I get to see it is when
the meter-reader guy comes around once a month to read it.

I suspect the meter is in a locked cabinet to prevent tampering / bypass
(the meter is inside the utility / furnace room of the building and is
not accessible from the outside).
==========

Based on the following (and others which I'm not including) I don't
think it's uncommon for billing meters to be located in locked cabinets,
or "cupboards" (a term used in the UK):



====================
http://www.horizonpower.com.au/downl...equirement.pdf

Multiple occupancy premises must have their meters readily accessible at
all times and comply with section 6 of the WAER, unless remote reading
facilities are installed. Where meters are located within a locked
meter-box/ cabinet or enclosed area, an approved Horizon Power master
lock must be fitted, allowing Horizon Power access to the meters at all
times. The disengaging of electronic security systems to obtain access
to the meters is not acceptable. Such cases will require an automated
reading system (AMR) to be installed.
====================

See also:

http://forums.moneysavingexpert.com/....php?t=2207277

And this:

==================
http://thestar.com.my/news/story.asp...46&sec=sarawak

See explained that Lee’s electricity meter was locked inside a
centralised cabinet outside his premises and three of the eight meters
inside the cabinet were found with signs of attempted tampering.
===================

And this:

=================
http://forums.whirlpool.net.au/archive/1414092

I live in a small townhouse block with 3 dwellings. We are in an Energy
Australia distribution area.

Our electricity meters are all together in a locked metal cabinet near
the street. These connect with underground wiring to a breaker box in
each house's garage.
==================

And this:

===============
http://www.theanswerbank.co.uk/Law/Question512492.html

When the houses were built, it was decided that the electricity meters
of each property would be placed in a 5ft x 3ft metal wall cabinet on
the outside gable end wall of an end property of each terrace of
houses. Recently, a new tenant has moved into the end property of my
terrace of houses and he has proved to be quite an objectionable and
difficult character. He is very unsympathetic towards my need to check
my meter and to make matters worse, the council has locked the cabinet
and provided him with a key just like they've done with other terrace
blocks on the estate.
=================

On 5/29/2011 8:59 AM, Home Guy wrote:
harry wrote:

Does a "demand meter" give a more accurate measure of energy
consumption?

(I note that no explicit answer is given for that question)

No. It's immaterial to the usage; only determines what the appropriate
rate will be. Again, that only will matter if you're actually on a
demand-based billing (which, personally, I would doubt for a small
office-type complex, but wouldn't be impossible).

....

So are you saying that customers with "demand meters" are billed on the
basis of their peak demand - a reading based on only a few minutes worth
of energy usage as seen over an entire billing period?

Yes

How is that a fair or equitable way to bill a customer?

What's "fair" got to do with it?

It's owing to the fact that as another already posted, facilities have
to be provided by the utility to handle the peak load; that costs more
so they bill more. It's also an incentive to the customer to look at
load-leveling techniques aggressively to cut their costs.

Are commercial customers that typically use between 2000 and 3000 kwh of
electricity per month normally considered as candidates for a demand
meter, or are they used for much higher usage customers?

Generally, much higher.

All you'll have to do is look at your bill and you'll know what the
tariff schedule is.

Again, you're looking in the wrong place here, first.

In all likelihood, the "problem" is _NOT_ in the metering but in either
having an unknown or parasitic load, the "reading" not being actual
reading but estimated until the "catch up" real reading at the beginning
of the year or other explainable issue. The likelihood of your meter
being in error is quite low for the explanation of the usage data you
previously posted.

--

"Home Guy" wrote
harry wrote:

Does a "demand meter" give a more accurate measure of energy
consumption?

(I note that no explicit answer is given for that question)

The accuracy is the same range as any other meter.



It only shows the maximum. Usually they only show peaks that
last a few minutes
The purpose of a demand meter is to discourage the electric
consumer from high peaks in demand. Usually there is an
additional charge that depends on this peak.

So are you saying that customers with "demand meters" are billed on the
basis of their peak demand - a reading based on only a few minutes worth
of energy usage as seen over an entire billing period?


There is some confusion here. Power factor then is the ratio of active
power to total power.
Power factor comes into play, mostly when you have a lot of large motors.
Yes, you set the reading during startup with the inefficient motors. You
can correct this by using a bank of capacitors properly sized. Or with a
capacitor at each of the large users, such as a 150 HP air compressor.

I don't claim to understand it all, but I do know it exists.
http://en.wikipedia.org/wiki/Power_factor
http://www.myronzucker.com/calmanualpg1.html


How is that a fair or equitable way to bill a customer?
Questionable, but done all the time.

On 5/29/2011 9:23 AM, Ed Pawlowski wrote:
....

How is that a fair or equitable way to bill a customer?
Questionable, but done all the time.

What's there to question about it?

As noted, the utility must supply the facilities and generation capacity
to satisfy peak demand, not average. That costs and the use of
demand-based tariffs provides a strong incentive to the end user to be
aggressive in implementing load-leveling techniques to the end benefit
of both utility and themselves.

--

On Sun, 29 May 2011 09:59:48 -0400, Home Guy wrote:


So are you saying that customers with "demand meters" are billed on the
basis of their peak demand - a reading based on only a few minutes worth
of energy usage as seen over an entire billing period?

No. As others have said, the peak determines the rate used. For
example, if your peak is below 5 KW, then you might be billed at 12
cents per KWH. If your peak goes above 5 KW, you might be billed at
15 cents per KWH. Those are just made up numbers. Your rates at
various peaks will be different. In summary, your peak is based on
just a few seconds, but you bill is still based on actual usage.

..

Instead of spending your time researching something actually useful
which might shed some light on what is actually going on (if anything
really is at all) you have chosen to ask stupid questions which are
clearly not on the proper wavelength to make any sense to someone
who actually understands electrical issues AND you are chasing after
something *YOU* can do which would support *YOUR* claim that
your electrical meter is not functioning correctly when there may
in fact be a procedure to follow which has already been defined by
the public utilities commission (or equivalent in your state) which
would almost always involve bringing in an uninterested third
party with the proper credentials and equipment to assess what
if anything is happening in this whole convoluted story...

It seems whenever you get some sound advise that would make
sense in the real world, you attack the contributor because the
person didn't respond with the specific answer you were looking
for in your especially preferred format... So you critique based
on newsgroup etiquette and posting format rather than the
supplied content -- keep doing that and you will be properly
labeled as a troll and written off as such...

~~ Evan
Hmmm,
BOTTOM LINEevery single dime.
Sounds like OP is Scrooge, will be only happy when he gets free power.
His building may be 100 years old containing industrial revolution era
stuffs.
Proper course of action would cost $$$ which is not in his book. My take
on this thread.

On May 29, 10:22*am, Home Guy wrote:
" wrote:
Here's a question no one has asked. *Why is the meter
in a box that is locked? *I've never seen this before.

That question was posed earlier in this thread, and I speculated as to
the reason for a locked cabinet in a post I made on Friday night (8:47
pm est):

============
The meter is in a locked cabinet. *The only time I get to see it is when
the meter-reader guy comes around once a month to read it.

I suspect the meter is in a locked cabinet to prevent tampering / bypass
(the meter is inside the utility / furnace room of the building and is
not accessible from the outside).
==========

Based on the following (and others which I'm not including) I don't
think it's uncommon for billing meters to be located in locked cabinets,
or "cupboards" (a term used in the UK):

====================http://www.horizonpower.com.au/downloads/comm_partners/metering/meter...

Multiple occupancy premises must have their meters readily accessible at
all times and comply with section 6 of the WAER, unless remote reading
facilities are installed. Where meters are located within a locked
meter-box/ cabinet or enclosed area, an approved Horizon Power master
lock must be fitted, allowing Horizon Power access to the meters at all
times. The disengaging of electronic security systems to obtain access
to the meters is not acceptable. Such cases will require an automated
reading system (AMR) to be installed.
====================


Seems a bit extreme. That says that the power company would
need not only a key to the meter box, but also a key to the business
to get inside anytime they want. A situation that would seem
to expose them to all kinds of potential security issues.

It also doesn't say that YOU cannot have a key as well.

Regardless of what is happening in other places, many
of them in other countries as outlined below,
have you asked the electric
company if you can have a key?




See also:

http://forums.moneysavingexpert.com/....php?t=2207277

And this:

==================http://thestar.com.my/news/story.asp?file=/2011/5/21/sarawak/8727246&...

See explained that Lee’s electricity meter was locked inside a
centralised cabinet outside his premises and three of the eight meters
inside the cabinet were found with signs of attempted tampering.
===================

And this:

=================http://forums.whirlpool.net.au/archive/1414092

I live in a small townhouse block with 3 dwellings. We are in an Energy
Australia distribution area.

Our electricity meters are all together in a locked metal cabinet near
the street. These connect with underground wiring to a breaker box in
each house's garage.
==================

And this:

===============http://www.theanswerbank.co.uk/Law/Question512492.html

When the houses were built, it was decided that the electricity meters
of each property would be placed in a 5ft x 3ft metal wall cabinet on
the outside gable end wall of an end property of each terrace of
houses. *Recently, a new tenant has moved into the end property of my
terrace of houses and he has proved to be quite an objectionable and
difficult character. He is very unsympathetic towards my need to check
my meter and to make matters worse, the council has locked the cabinet
and provided him with a key just like they've done with other terrace
blocks on the estate.
=================

wrote:
Here's a question no one has asked. Why is the meter
in a box that is locked? I've never seen this before.
Do you know if similar meters are all locked? Why
not ask the electric company to leave the box unlocked?
That way at least you could see what the actual meter
is doing.
Hi,
Often saw in my working days, meter inside a box but it always had an
opening(window) so one can see the reading and so on.

wrote in message
...
On Sun, 29 May 2011 09:59:48 -0400, Home Guy wrote:


So are you saying that customers with "demand meters" are billed on the
basis of their peak demand - a reading based on only a few minutes worth
of energy usage as seen over an entire billing period?

No. As others have said, the peak determines the rate used. For
example, if your peak is below 5 KW, then you might be billed at 12
cents per KWH. If your peak goes above 5 KW, you might be billed at
15 cents per KWH. Those are just made up numbers. Your rates at
various peaks will be different. In summary, your peak is based on
just a few seconds, but you bill is still based on actual usage.

** The point being, if you are totally ignorant as to how the dollar amount
on the electric bill is determined, the first place to ask questions is the
company supplying the electricity and providing the bill. Once you get all
those nasty details figured out, you'll have a better idea of how to go
about verifying the numbers

"Home Guy" wrote
Poor every future poster to any newsgroup that asks a simple technical
question and gets told by the peanut gallery that it's important to know
all the ancilliary circumstances surrounding the question when in
reality in the end those circumstances have no bearing on the question
or it's answer.

I'd agree with you if you were right, but in all likelihood, you are not.
I've been hanging around USENET for about 15+ years now. I've seen too many
question asked, answered, and later find that the real answer is something
far different because important facts were left out.

On Sun, 29 May 2011 13:27:46 -0400, Home Guy wrote:

" wrote:

Power factor comes into play, mostly when you have a lot of large
motors.

If the motors are fully loaded the PF will be close to one.

In actuality, the larger the motor, the greater will be it's power
factor.

Fractional HP motors (1/8, 1/4, 1/3, 1/2, etc) have low power factors
(37% to 66%).

Motors above a dozen hp have power factors of 85% or better.
Those motors are only better because they are usually sized properly
and are running near their rating. If you lightly load such a motor,
it still can draw a lot of current, but out of phase with the voltage.
Little real power is being used, but lots of VAs. Another way of
looking at it is a lightly loaded motor is acting like an inductor.
The more real mechanical load applied to the motor, the more real
electrical power is required. The motor looks more and more like a
resistor as the power reaches the design limits of the motor.

Home Guy wrote:

So are you saying that customers with "demand meters" are billed on
the basis of their peak demand - a reading based on only a few
minutes worth of energy usage as seen over an entire billing period?

How is that a fair or equitable way to bill a customer?


Because the cost to generate the electricity is small compared to the cost
to deliver the energy. The cost to deliver the energy, in turn, is
determined by the infrastructure needed (poles, transformers, generation
capability, etc.). A commercial customer with even a short peak demand may
require more infrastructure to support that demand than dozens of
residential customers.

HeyBub wrote:

So are you saying that customers with "demand meters" are billed
on the basis of their peak demand - a reading based on only a
few minutes worth of energy usage as seen over an entire billing
period?

How is that a fair or equitable way to bill a customer?


Because the cost to generate the electricity is small compared to
the cost to deliver the energy. The cost to deliver the energy,
in turn, is determined by the infrastructure needed (poles,
transformers, generation capability, etc.). A commercial customer
with even a short peak demand may require more infrastructure to
support that demand than dozens of residential customers.

So what would you consider or where would you place the threshold for
which demand metering should be used by a customer?

What monthly kwh usage would you consider "worthy" or significant enough
for an electricity supplier to use a demand meter to cover this
so-called significant cost of delivering this huge amount of brief peak
energy?

Would you consider, say, 2000 kwh? Would a single month's total usage
of 2000 kwh qualify a customer for a demand meter? Would 4 consecutive
months of 2000 kwh be the line-in-the-sand for putting a customer on a
demand meter?

http://www.nationalgridus.com/niagar...lec-demand.pdf

Demand meters for such small users are total bull****.

Anyone with a 100 amp, single-phase service that is using their service
at 50% for an entire month would tip the scale at a 4300 kwh bill.
Hardly what I'd call justified for utilizing 50% of the smallest
installable utility service.

How would you justify the infrastructure costs needed to supply such a
paltry service such that demand metering is needed?

On 5/29/2011 8:04 PM, Home Guy wrote:
....

How would you justify the infrastructure costs needed to supply such a
paltry service such that demand metering is needed?

On the basis that it the assertion that it's not generation but
transmission only that matters--it's both.

Given the restrictions on new generation facilities and tightening
regulation on existing, if there's any growth in demand there's getting
to be nowhere from which to get it.

Applying demand metering shifts (or at least increases) the interest of
the user that previously hasn't ever cared by the only really effective
behavior-changing device--the pocketbook.

--

On Sun, 29 May 2011 21:04:29 -0400, Home Guy wrote:

HeyBub wrote:

So are you saying that customers with "demand meters" are billed
on the basis of their peak demand - a reading based on only a
few minutes worth of energy usage as seen over an entire billing
period?

How is that a fair or equitable way to bill a customer?


Because the cost to generate the electricity is small compared to
the cost to deliver the energy. The cost to deliver the energy,
in turn, is determined by the infrastructure needed (poles,
transformers, generation capability, etc.). A commercial customer
with even a short peak demand may require more infrastructure to
support that demand than dozens of residential customers.

So what would you consider or where would you place the threshold for
which demand metering should be used by a customer?

What monthly kwh usage would you consider "worthy" or significant enough
for an electricity supplier to use a demand meter to cover this
so-called significant cost of delivering this huge amount of brief peak
energy?

It's not the monthly kWh usage that determines whether demand metering is used
or useful. It's the *peak* usage and when that peak occurs. The
infrastructure has to be built for the largest demand, not average. Where the
threshold is placed is a different matter for each power company.

Would you consider, say, 2000 kwh? Would a single month's total usage
of 2000 kwh qualify a customer for a demand meter? Would 4 consecutive
months of 2000 kwh be the line-in-the-sand for putting a customer on a
demand meter?

I don't believe any residential customers have demand metering, but I could be
wrong.

http://www.nationalgridus.com/niagar...lec-demand.pdf

Demand meters for such small users are total bull****.

Define "such small".

Anyone with a 100 amp, single-phase service that is using their service
at 50% for an entire month would tip the scale at a 4300 kwh bill.
Hardly what I'd call justified for utilizing 50% of the smallest
installable utility service.

You wouldn't have demand metering with a 100A service. ...at least not a
residential service.

How would you justify the infrastructure costs needed to supply such a
paltry service such that demand metering is needed?

On May 29, 10:11*pm, "
wrote:
On Sun, 29 May 2011 21:04:29 -0400, Home Guy wrote:
HeyBub wrote:

So are you saying that customers with "demand meters" are billed
on the basis of their peak demand - a reading based on only a
few minutes worth of energy usage as seen over an entire billing
period?

How is that a fair or equitable way to bill a customer?

Because the cost to generate the electricity is small compared to
the cost to deliver the energy. The cost to deliver the energy,
in turn, is determined by the infrastructure needed (poles,
transformers, generation capability, etc.). A commercial customer
with even a short peak demand may require more infrastructure to
support that demand than dozens of residential customers.

So what would you consider or where would you place the threshold for
which demand metering should be used by a customer?

What monthly kwh usage would you consider "worthy" or significant enough
for an electricity supplier to use a demand meter to cover this
so-called significant cost of delivering this huge amount of brief peak
energy?

It's not the monthly kWh usage that determines whether demand metering is used
or useful. *It's the *peak* usage and when that peak occurs. *The
infrastructure has to be built for the largest demand, not average. *Where the
threshold is placed is a different matter for each power company.

Would you consider, say, 2000 kwh? *Would a single month's total usage
of 2000 kwh qualify a customer for a demand meter? *Would 4 consecutive
months of 2000 kwh be the line-in-the-sand for putting a customer on a
demand meter?

I don't believe any residential customers have demand metering, but I could be
wrong.

http://www.nationalgridus.com/niagar...lec-demand.pdf

Demand meters for such small users are total bull****.

Define "such small".

Anyone with a 100 amp, single-phase service that is using their service
at 50% for an entire month would tip the scale at a 4300 kwh bill.
Hardly what I'd call justified for utilizing 50% of the smallest
installable utility service.

You wouldn't have demand metering with a 100A service. *...at least not a
residential service.




yes you might. APS in Arizona offers demand metering to residential
customers, (at least they did when I lived there)

The so called PEAK demand was based on the highest power used during
any 60 minute period over the billing period. With demand metering,
they lower the kWh rate but they charge you also for the peak. For
example, with standard billing you might pay $0.12 per kWh. With
demand billing you would pay $0.06 per kHW plus $5.00 per peak kWh.
So for example if I used 100kWh during and a peak of 5 kWh during the
month the charge would be $60 plus $25. If you are just a little
careful you can save a lot of money. If you are just a little
careless it can cost you a lot of money.

Also following this thread some of you seem to be mixing up power
factor and demand billing, they are two different things. Some
industrial billing plans bill by kWh, peak kWh AND power factor.

Mark

"dpb" wrote in message ...
On 5/29/2011 8:59 AM, Home Guy wrote:
harry wrote:

Does a "demand meter" give a more accurate measure of energy
consumption?

(I note that no explicit answer is given for that question)

No. It's immaterial to the usage; only determines what the appropriate
rate will be.

I wouldn't say it that way. It's very material in that (as you clarify) it
sets the rate for the usage. Just nit-picking to make it clear to the OP
that there are two very clearly different factors to consider in business
rates that are different from residential rates. A power blip that ended up
turning every device on simultaneously (a rare situation - except for X-10
users g) could be an extremely costly event. Why? Because peak demand
rates are set by the maximum power ever used during the metering period.
The OP could have easily changed the dynamics of his billing by plugging in
a couple of new space heaters at exactly the wrong time. That sort of event
could easily explain why the OP finds himself owing a lot more money than
last year even though the kWh used could be virtually identical.

Again, that only will matter if you're actually on a
demand-based billing (which, personally, I would doubt for a small
office-type complex, but wouldn't be impossible).

I've learned (the very hard way) that with posters here from all over the
world, many of the things I thought were customary nation or world-wide are
just local quirks. (-:

So are you saying that customers with "demand meters" are billed on the
basis of their peak demand - a reading based on only a few minutes worth
of energy usage as seen over an entire billing period?

Yes

How is that a fair or equitable way to bill a customer?

What's "fair" got to do with it?

"Deserves got nothing to do with it" - Unforgiven

It's owing to the fact that as another already posted, facilities have
to be provided by the utility to handle the peak load; that costs more
so they bill more. It's also an incentive to the customer to look at
load-leveling techniques aggressively to cut their costs.

Are commercial customers that typically use between 2000 and 3000 kwh of
electricity per month normally considered as candidates for a demand
meter, or are they used for much higher usage customers?

Generally, much higher.

All you'll have to do is look at your bill and you'll know what the
tariff schedule is.

Again, you're looking in the wrong place here, first.

No, I beg to differ. I always feel much more comfortable encountering
service personnel and such knowing as much as I can learn elsewhere. I
believe the OP has learned a great deal from this thread and could get to
the point where an encounter isn't even necessary. His bill probably holds
the sad tale of a one time excursion into a higher rate zone that's cost him
big time. I'll bet he now becomes very aggressive managing his peak load.

I would suggest dropping $25 for a basic Kil-O-Wat plug in meter

http://www.newegg.com/Product/Produc...82E16882715001

to measure the current draw of all his equipment. Then I'd figure out some
sort of switching interlock or timer system to insure that loads don't all
coincide.

In all likelihood, the "problem" is _NOT_ in the metering but in either
having an unknown or parasitic load, the "reading" not being actual
reading but estimated until the "catch up" real reading at the beginning
of the year or other explainable issue. The likelihood of your meter
being in error is quite low for the explanation of the usage data you
previously posted.

Which is why I recommend the Kil-O-Watt meter. You can measure each device
(except hard-wired ones) and get a true reading (wattage or V/A) of its
instantaneous power consumption or the consumption over a period of time.
A clamp meter is a good way to measure the items hardwired to the circuit
panel, but it's pretty lousy for determining wattage or power consumption
over time for stand-alone devices.

-
Bobby G.