On Tue, 22 Nov 2005 16:05:54 -0500, "Brent Atkerson"
wrote:

This one interests me. Wonder how many small UPSs you could run from a
truck battery (assuming using heavy enough cables between each UPS and each
battery [when needed for the 24 volt input]). I am sure you would have to
leave the vehicle running if running the UPSs for any length of time or
heavy load... Probably pretty basic questions but I am kind of interested
because I have a couple laying around and never thought of using them as an
inverter (powered by a vehicle). That would make a neat addition to a
garden tractor or something too...

Better check first if the UPS can handle a log term run of a battery. It
might be that it was designed for a short term, just to give you enough time
to power everything down properly. Longer runt time might cause some
marginal designs to overheat.



Regards,

Boris Mohar

Got Knock? - see:
Viatrack Printed Circuit Designs (among other things) http://www.viatrack.ca

void _-void-_ in the obvious place

On Wed, 23 Nov 2005 00:38:17 -0500,
wrote:
On Tue, 22 Nov 2005 12:55:29 -0800, "Bob Headrick"
wrote:
"Highland Ham" wrote in message
. ..

Bob , Interesting info ; can you confirm that the 18 pcs 12V battery were
in fact 9 strings of 2 batts in series (each string having a fuse )
providing 24 V ? or were all the 18 batts in parallel ?

Actually they were all in series, making it a bit nerve-wracking to replace a
battery in the string.

216 volt battery pack??? I don't think so.

No, quite possible and makes some design sense - they would not need
a heavy output transformer in the unit boosting the voltage of a 36V
or 48V battery string after converting it to a sine wave AC, as 216V
would be right around the sine wave peak voltage of 120VAC. Just run
the battery DC through two sets of power transistors to let through a
reconstituted sine wave - one for the positive half of the output
waveform, the other negative.

And it cuts the current the transistors have to pass.

-- Bruce --

--
Bruce L. Bergman, Woodland Hills (Los Angeles) CA - Desktop
Electrician for Westend Electric - CA726700
5737 Kanan Rd. #359, Agoura CA 91301 (818) 889-9545
Spamtrapped address: Remove the python and the invalid, and use a net.

On Sun, 20 Nov 2005 21:14:33 -0800, Too_Many_Tools wrote:

I am the "lucky" owner of a number of older UPSes.

So what can a person build out of these?

The batteries are for the most part dead but the remainder of the
components seem to be in good condition.

Any suggestions?


Sell them to FedEx? ;-)
--
Cheers!
Rich
------
"Grain grows best in ****."
-- U.K. LeGuin

On Wed, 23 Nov 2005 16:22:24 GMT, Ignoramus22022
wrote:
On Wed, 23 Nov 2005 16:13:58 GMT, Bruce L Bergman wrote:
On Wed, 23 Nov 2005 wrote:
On Tue, 22 Nov 2005 12:55:29 -0800, "Bob Headrick" wrote:
"Highland Ham" wrote:

Bob , Interesting info ; can you confirm that the 18 pcs 12V battery were
in fact 9 strings of 2 batts in series (each string having a fuse )
providing 24 V ? or were all the 18 batts in parallel ?

Actually they were all in series, making it a bit nerve-wracking to replace a
battery in the string.

216 volt battery pack??? I don't think so.

No, quite possible and makes some design sense - they would not need
a heavy output transformer in the unit boosting the voltage of a 36V
or 48V battery string after converting it to a sine wave AC, as 216V
would be right around the sine wave peak voltage of 120VAC. Just run
the battery DC through two sets of power transistors to let through a
reconstituted sine wave - one for the positive half of the output
waveform, the other negative.

And it cuts the current the transistors have to pass.

Bruce, this also sounds like a simple approach to generating 3 phase
out of DC. Without the noise and weight of rotary phase
converters. What are your thoughts on that?

Quite Plausible, but when you add the caveat of reproducing 3-Phase
power the engineering just got really complicated, and more than
likely rather expensive. And I'm NOT a high-powered electronics drive
wonk by any means, the best I could do for fixing them is look for the
obviously crispy components and swap out the blown boards - or swap
the crispy parts and diodes that fail a VOM test and see if that does
it.

With a single phase inverter, they're just doing a push-pull on one
240V lead, relative to the center tapped neutral. When you try
3-phase, there's going to be constant voltage, current and capacitance
interaction between all three sets of "hot AC" switching transistors
(or Triacs, or whatever). And the load's resistive, inductive and
capacitive components are all going to come into play.

The resulting inverter would need to be built rather robust, and be
able to overcome drive issues with brute force where finesse won't do.
Compared to that, RPC's are the KISS method. And RPC's aren't a bad
way to go, if they are well balanced and have cooling air you can tuck
them away in a closet.

-- Bruce --

--
Bruce L. Bergman, Woodland Hills (Los Angeles) CA - Desktop
Electrician for Westend Electric - CA726700
5737 Kanan Rd. #359, Agoura CA 91301 (818) 889-9545
Spamtrapped address: Remove the python and the invalid, and use a net.

Ignoramus22022 wrote:

On Wed, 23 Nov 2005 23:21:02 GMT, Bruce L Bergman wrote:
On Wed, 23 Nov 2005 16:22:24 GMT, Ignoramus22022
wrote:
On Wed, 23 Nov 2005 16:13:58 GMT, Bruce L Bergman wrote:
On Wed, 23 Nov 2005 wrote:
On Tue, 22 Nov 2005 12:55:29 -0800, "Bob Headrick" wrote:
"Highland Ham" wrote:

Bob , Interesting info ; can you confirm that the 18 pcs 12V battery were
in fact 9 strings of 2 batts in series (each string having a fuse )
providing 24 V ? or were all the 18 batts in parallel ?

Actually they were all in series, making it a bit nerve-wracking to replace a
battery in the string.

216 volt battery pack??? I don't think so.

No, quite possible and makes some design sense - they would not need
a heavy output transformer in the unit boosting the voltage of a 36V
or 48V battery string after converting it to a sine wave AC, as 216V
would be right around the sine wave peak voltage of 120VAC. Just run
the battery DC through two sets of power transistors to let through a
reconstituted sine wave - one for the positive half of the output
waveform, the other negative.

And it cuts the current the transistors have to pass.

Bruce, this also sounds like a simple approach to generating 3 phase
out of DC. Without the noise and weight of rotary phase
converters. What are your thoughts on that?

Quite Plausible, but when you add the caveat of reproducing 3-Phase
power the engineering just got really complicated, and more than
likely rather expensive. And I'm NOT a high-powered electronics drive
wonk by any means, the best I could do for fixing them is look for the
obviously crispy components and swap out the blown boards - or swap
the crispy parts and diodes that fail a VOM test and see if that does
it.

With a single phase inverter, they're just doing a push-pull on one
240V lead, relative to the center tapped neutral.

Right. As you know, I recently made a DC - AC inverter myself.

When you try 3-phase, there's going to be constant voltage, current
and capacitance interaction between all three sets of "hot AC"
switching transistors (or Triacs, or whatever). And the load's
resistive, inductive and capacitive components are all going to come
into play.

Yep.

The resulting inverter would need to be built rather robust, and be
able to overcome drive issues with brute force where finesse won't do.
Compared to that, RPC's are the KISS method. And RPC's aren't a bad
way to go, if they are well balanced and have cooling air you can tuck
them away in a closet.

You are right. I am going to redo my RPC into a 17.5 HP RPC. (two
motors, 10 and 7.5 HP). Right now I have a 10 HP RPC.

Someone offered me a Semikron 6 IGBT drive, with which I could make a
3 phase inverter. That sort of made me interested.

i

Get your hands on a large, like 30kw or better, used as in "please take
it out of here", three phase, online UPS from a computer room
installation. As long as you can supply adequate power to the DC bus the
inverter portion will happily generate your three phase power with no
issues with designing and inverter or trying to synchronize three
inverters or duty cycle problems. It's a DC - 3 phase AC continuous duty
inverter, ready-to-go.

Pete C.

Ignoramus22022 wrote:

On Thu, 24 Nov 2005 01:04:56 GMT, Pete C. wrote:
Ignoramus22022 wrote:

On Wed, 23 Nov 2005 23:21:02 GMT, Bruce L Bergman wrote:
On Wed, 23 Nov 2005 16:22:24 GMT, Ignoramus22022
wrote:
On Wed, 23 Nov 2005 16:13:58 GMT, Bruce L Bergman wrote:
On Wed, 23 Nov 2005 wrote:
On Tue, 22 Nov 2005 12:55:29 -0800, "Bob Headrick" wrote:
"Highland Ham" wrote:

Bob , Interesting info ; can you confirm that the 18 pcs 12V battery were
in fact 9 strings of 2 batts in series (each string having a fuse )
providing 24 V ? or were all the 18 batts in parallel ?

Actually they were all in series, making it a bit nerve-wracking to replace a
battery in the string.

216 volt battery pack??? I don't think so.

No, quite possible and makes some design sense - they would not need
a heavy output transformer in the unit boosting the voltage of a 36V
or 48V battery string after converting it to a sine wave AC, as 216V
would be right around the sine wave peak voltage of 120VAC. Just run
the battery DC through two sets of power transistors to let through a
reconstituted sine wave - one for the positive half of the output
waveform, the other negative.

And it cuts the current the transistors have to pass.

Bruce, this also sounds like a simple approach to generating 3 phase
out of DC. Without the noise and weight of rotary phase
converters. What are your thoughts on that?

Quite Plausible, but when you add the caveat of reproducing 3-Phase
power the engineering just got really complicated, and more than
likely rather expensive. And I'm NOT a high-powered electronics drive
wonk by any means, the best I could do for fixing them is look for the
obviously crispy components and swap out the blown boards - or swap
the crispy parts and diodes that fail a VOM test and see if that does
it.

With a single phase inverter, they're just doing a push-pull on one
240V lead, relative to the center tapped neutral.

Right. As you know, I recently made a DC - AC inverter myself.

When you try 3-phase, there's going to be constant voltage, current
and capacitance interaction between all three sets of "hot AC"
switching transistors (or Triacs, or whatever). And the load's
resistive, inductive and capacitive components are all going to come
into play.

Yep.

The resulting inverter would need to be built rather robust, and be
able to overcome drive issues with brute force where finesse won't do.
Compared to that, RPC's are the KISS method. And RPC's aren't a bad
way to go, if they are well balanced and have cooling air you can tuck
them away in a closet.

You are right. I am going to redo my RPC into a 17.5 HP RPC. (two
motors, 10 and 7.5 HP). Right now I have a 10 HP RPC.

Someone offered me a Semikron 6 IGBT drive, with which I could make a
3 phase inverter. That sort of made me interested.

i

Get your hands on a large, like 30kw or better, used as in "please take
it out of here", three phase, online UPS from a computer room
installation. As long as you can supply adequate power to the DC bus the
inverter portion will happily generate your three phase power with no
issues with designing and inverter or trying to synchronize three
inverters or duty cycle problems. It's a DC - 3 phase AC continuous duty
inverter, ready-to-go.

A 30 kVa UPS would weigh approximately a ton. That's without
batteries. It is beyond what I can handle.

No way, I put in a 30kw 3 phase UPS (Best Unity/1) and it was close to a
ton with batteries. Without batteries (when I moved it across a raised
floor with a pallet jack) it was far under a ton.


Since it needs a system for producing DC, it would be comparable to
what the UPS already has.

It has a system for producing DC, it's just setup for three phase input.
Depending on how it is configured it could be quite easy to rework the
input section for single phase. The more modular the design the better
and you might get lucky and find three discrete DC supplies, one fed
from each phase, that couldn't care less if they were actually 120
degrees apart.


That means that I would have a monster that weighs a ton.

That would mean you have all the clean sine wave three phase power your
shop could need, uninterruptable no less, and heat for the winter.


I almost bought a 15 kVa UPS though.

i

The building I used to work in had about six monster UPSes in the
basement, each feeding a 600A 208/120V 3 phase buss duct running up
through the building to multiple PDUs. They had the nice 5 gal size
glass cased batteries in the strings. Also had five 800KW diesel
generators with paralleling switch gear and 40,000 gal of fuel supply.
Redundant utility feeds as well. Place would have made a nice house if
it was in a better location

Pete C.

Thanks for the input! I'll get out the Fluke and download the .PDF and see
what I can find before I burn the place down I was sort of hoping to be
able to replace the stock batteries but they are so insanely expensive,
hacking the box for batteries I have no use for (Still in the plastic wrap
and caps on. got them in a barter) Get this- Mercedes wanted $430.00 to
replace my battery for P/M- Yea right, my car now has a Optima yellow in the
trunk and why a factory (much smaller and lighter too) battery would be junk
after two years blows my mind.

Thanks for the info and help!

Rob Fraser


Fraser Competition Engines
Chicago, IL.


"Highland Ham" wrote in message
...
Would a 12 V deep cycle- Optima work in a APC-UPS 1400R I keep my servers
and dyno on with it along with some routers and switches. I don't know
the output, the battery fails and I now have it frightfully bypassed. The
batteries died and are almost 2 bills to replace. voltages ? issues? but
I have a few Optima batteries from wrecked race cars that would be
perfect!
===================
Suggest you check the charging instructions on the original battery and
compare these with the ones applicable to the Optima type of battery.
The battery in a UPS is on 'standby duty' The charging instruction for a
YUASA SLA found in many UPSes has the following for standby duty :
Voltage regulation : 13.5 - 13.8 V
Initial current : Unlimited

Connect the Optima battery to the UPS and check the voltage when the
battery is fully charged . You can charge the battery externally to say
13.5 volt before you connect it to the UPS. If the fully charged
voltage is in the above range ,you can safely use it for this purpose.
I would think that any 12 V SLA will happily work with your APC UPS 1400R
,provided its capacity is adequate for the load to be maintained for the
minimum time needed. If you use a number of batts in parallel ,please
ensure there is an adequate FUSE in each battery circuit !
You can also connect a much larger 12 V sealed battery to the UPS (for
example those used in electric golf trolleys). Even non-sealed batts can
be used provided they are located in a well ventilated area .
I have non-sealed batts located on the loft connected via leads made from
welding cable running to equipment in the ground floor radio shack ( to
feed radio equipment requiring a peak current not exceeding 25 Amperes)

Above I mentioned batts for Golf trolleys because their cost is very
reasonable nowadays there being a relatively large demand , hence
competition (pun intended)

Frank GMØCSZ / KN6WH

RDF wrote:

Thanks for the input! I'll get out the Fluke and download the .PDF and see
what I can find before I burn the place down I was sort of hoping to be
able to replace the stock batteries but they are so insanely expensive,
hacking the box for batteries I have no use for (Still in the plastic wrap
and caps on. got them in a barter) Get this- Mercedes wanted $430.00 to
replace my battery for P/M- Yea right, my car now has a Optima yellow in the
trunk and why a factory (much smaller and lighter too) battery would be junk
after two years blows my mind.

Thanks for the info and help!

Rob Fraser

Fraser Competition Engines
Chicago, IL.

The VP of my department found the same thing with the battery in his
BMW. He decided that the zillion dollar original was BS so I sent him to
my favorite battery distributor for an Optima and helped him retrofit
the hold down.

Pete C.

Pete - the building didn't have windows - so you could put a couch anywhere and
a lathe anywhere without problems of a window in the way.

Heavy duty buildings are going to become rare due to the shear cost of building.
Such is life.

Martin
Martin Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
NRA LOH, NRA Life
NRA Second Amendment Task Force Charter Founder



Pete C. wrote:
snip...

No way, I put in a 30kw 3 phase UPS (Best Unity/1) and it was close to a
ton with batteries. Without batteries (when I moved it across a raised
floor with a pallet jack) it was far under a ton.


Since it needs a system for producing DC, it would be comparable to
what the UPS already has.


It has a system for producing DC, it's just setup for three phase input.
Depending on how it is configured it could be quite easy to rework the
input section for single phase. The more modular the design the better
and you might get lucky and find three discrete DC supplies, one fed
from each phase, that couldn't care less if they were actually 120
degrees apart.


That means that I would have a monster that weighs a ton.


That would mean you have all the clean sine wave three phase power your
shop could need, uninterruptable no less, and heat for the winter.


I almost bought a 15 kVa UPS though.

i


The building I used to work in had about six monster UPSes in the
basement, each feeding a 600A 208/120V 3 phase buss duct running up
through the building to multiple PDUs. They had the nice 5 gal size
glass cased batteries in the strings. Also had five 800KW diesel
generators with paralleling switch gear and 40,000 gal of fuel supply.
Redundant utility feeds as well. Place would have made a nice house if
it was in a better location

Pete C.

----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups
----= East and West-Coast Server Farms - Total Privacy via Encryption =----

Pete,
I hear ya- loud and clear. This one is even better. At 30k the P/M is to
replace the serpentine belt (fully logical) I asked "How much" expecting
about $30.00 He told me $220.79 Now, my car has my company name and graphic
on the trunk lid, I asked the guy if it was correct and he reassured me it
was and it needed a "special tool" to change it. So in I peek. Went and got
a 4" C- clamp to compress a hydraulic cylinder to maintain pressure on the
tensioner and installed a Gates Powergrip belt ( at a whopping $14.99 at
NAPA) I wonder what a $200.00 C-clamp does
Moral of the story- I'm not the brightest guy on the planet but that is
plain theft. And people pay it, I feel sorry for them. This is why I had my
ex-girlfriend's daughter take autoshop and work for me in the summer. Let
some other sucker bite that hook. That in itself justified me buying a
complete factory service manual and a Benz logic cartridge set for my
Snap-On scanner. Hell, I would have spent that on a belt alone from the
dealer.

I know it's very OT but it just leaves me angry to recall it and think
I'd go for it.

All the best,

Rob Fraser


Fraser Competition Engines
Chicago, IL.
"Pete C." wrote in message
...
RDF wrote:

Thanks for the input! I'll get out the Fluke and download the .PDF and
see
what I can find before I burn the place down I was sort of hoping to
be
able to replace the stock batteries but they are so insanely expensive,
hacking the box for batteries I have no use for (Still in the plastic
wrap
and caps on. got them in a barter) Get this- Mercedes wanted $430.00 to
replace my battery for P/M- Yea right, my car now has a Optima yellow in
the
trunk and why a factory (much smaller and lighter too) battery would be
junk
after two years blows my mind.

Thanks for the info and help!

Rob Fraser

Fraser Competition Engines
Chicago, IL.

The VP of my department found the same thing with the battery in his
BMW. He decided that the zillion dollar original was BS so I sent him to
my favorite battery distributor for an Optima and helped him retrofit
the hold down.

Pete C.

RDF wrote:

Pete,
I hear ya- loud and clear. This one is even better. At 30k the P/M is to
replace the serpentine belt (fully logical) I asked "How much" expecting
about $30.00 He told me $220.79 Now, my car has my company name and graphic
on the trunk lid, I asked the guy if it was correct and he reassured me it
was and it needed a "special tool" to change it. So in I peek. Went and got
a 4" C- clamp to compress a hydraulic cylinder to maintain pressure on the
tensioner and installed a Gates Powergrip belt ( at a whopping $14.99 at
NAPA) I wonder what a $200.00 C-clamp does
Moral of the story- I'm not the brightest guy on the planet but that is
plain theft. And people pay it, I feel sorry for them. This is why I had my
ex-girlfriend's daughter take autoshop and work for me in the summer. Let
some other sucker bite that hook. That in itself justified me buying a
complete factory service manual and a Benz logic cartridge set for my
Snap-On scanner. Hell, I would have spent that on a belt alone from the
dealer.

I know it's very OT but it just leaves me angry to recall it and think
I'd go for it.

All the best,

Rob Fraser

Fraser Competition Engines
Chicago, IL.

With each new vehicle I have owned, I have ordered the factory service
manual(s) at the same time I ordered the vehicle. I can't understand
people who whine about a $100 manual set when they just spent $30,000 or
more on the vehicle. I've read every one of those manuals cover to cover
several times and you learn quite a bit.

Pete C.

On Fri, 25 Nov 2005 05:34:47 GMT, Ignoramus10725
wrote:

On Thu, 24 Nov 2005 21:43:24 -0600, RDF wrote:
Pete,
I hear ya- loud and clear. This one is even better. At 30k the P/M is to
replace the serpentine belt (fully logical) I asked "How much" expecting
about $30.00 He told me $220.79 Now, my car has my company name and graphic
on the trunk lid, I asked the guy if it was correct and he reassured me it
was and it needed a "special tool" to change it. So in I peek. Went and got
a 4" C- clamp to compress a hydraulic cylinder to maintain pressure on the
tensioner and installed a Gates Powergrip belt ( at a whopping $14.99 at
NAPA) I wonder what a $200.00 C-clamp does
Moral of the story- I'm not the brightest guy on the planet but that is
plain theft. And people pay it, I feel sorry for them. This is why I had my
ex-girlfriend's daughter take autoshop and work for me in the summer. Let
some other sucker bite that hook. That in itself justified me buying a
complete factory service manual and a Benz logic cartridge set for my
Snap-On scanner. Hell, I would have spent that on a belt alone from the
dealer.

I do not even bother looking for honest car mechanics anymore. I gave
up. I do everything I can do on my truck, myself. If that takes buying
tools, usually I buy tools as it turns out to be cheaper anyway.

Furthermore, I even do not deal with car mechanics when they try to
sell their used stuff (my hobby is to resell used equipment on ebay).

As soon as I learn that the seller is a car mechanic, I say something
polite and hang up. That's not out of bitterness or some such, this
policy does not make me lose money. I just know that I would come in,
he would be unreasonable in his asking prices and likely even
impolite, and try to screw me in every way he can.

i

Too bad all you've met are the bad ones. There are a few good ones
left - but most of US have gotten out.(which leaves only the bad ones
for you to deal with).
I got out, largely, because the CUSTOMERS are unpolite,
demanding,dishonest, cheap, and generally impossible to satisfy - even
when you do something for nothing.
They book their car for 3 hours of work and don't show up, after you
have made room in your busy schedule to get them in NOW - and that is
only because it is IMPOSSIBLE to do it yesterday. Then they want you
to diagnose the problem over the phone and guarantee the price - AND
be cheaper than the other 10 or 12 mechanics they have done the same
thing to. If you can't get the parts PRONTO, they cry and complain -
and you can NOT have every possible part available - the dealers don't
either. Then they lie about what has happened to the car, because they
want it to be someone elses fault and problem, not their own.
You fix the car and they leave and stop payment on the check or
dispute the charge on their credit card. Not only that, they bad-mouth
you to everyone who will listen when at the bar, a party, or wherever,
whenever the subject of auto repair or car problems comes up - which
is ANY time. Then 3 months later, after you have fixed, say the
brakes, they come back with the wiper motor not working - and - you
guessed it - its YOUR fault!!!!


It just wasn't fun any more after 25 years - and its gotten a whole
lot worse in the last 15 or more years.

I know it's very OT but it just leaves me angry to recall it and think
I'd go for it.

All the best,

Rob Fraser


Fraser Competition Engines
Chicago, IL.
"Pete C." wrote in message
...
RDF wrote:

Thanks for the input! I'll get out the Fluke and download the .PDF and
see
what I can find before I burn the place down I was sort of hoping to
be
able to replace the stock batteries but they are so insanely expensive,
hacking the box for batteries I have no use for (Still in the plastic
wrap
and caps on. got them in a barter) Get this- Mercedes wanted $430.00 to
replace my battery for P/M- Yea right, my car now has a Optima yellow in
the
trunk and why a factory (much smaller and lighter too) battery would be
junk
after two years blows my mind.

Thanks for the info and help!

Rob Fraser

Fraser Competition Engines
Chicago, IL.

The VP of my department found the same thing with the battery in his
BMW. He decided that the zillion dollar original was BS so I sent him to
my favorite battery distributor for an Optima and helped him retrofit
the hold down.

Pete C.

wrote:


Too bad all you've met are the bad ones. There are a few good ones
left - but most of US have gotten out.(which leaves only the bad ones
for you to deal with).
I got out, largely, because the CUSTOMERS are unpolite,
demanding,dishonest, cheap, and generally impossible to satisfy - even
when you do something for nothing.
They book their car for 3 hours of work and don't show up, after you
have made room in your busy schedule to get them in NOW - and that is
only because it is IMPOSSIBLE to do it yesterday. Then they want you
to diagnose the problem over the phone and guarantee the price - AND
be cheaper than the other 10 or 12 mechanics they have done the same
thing to. If you can't get the parts PRONTO, they cry and complain -
and you can NOT have every possible part available - the dealers don't
either. Then they lie about what has happened to the car, because they
want it to be someone elses fault and problem, not their own.
You fix the car and they leave and stop payment on the check or
dispute the charge on their credit card. Not only that, they bad-mouth
you to everyone who will listen when at the bar, a party, or wherever,
whenever the subject of auto repair or car problems comes up - which
is ANY time. Then 3 months later, after you have fixed, say the
brakes, they come back with the wiper motor not working - and - you
guessed it - its YOUR fault!!!!


Not entirely true, the few lucky people who have been able to find
honest, reliable mechanics do tend to speak highly of them.


It just wasn't fun any more after 25 years - and its gotten a whole
lot worse in the last 15 or more years.

Remember that the people bringing in the cars in the last 15 years or so
as you have noted, are the parents (or now their children) from the
generation that has deluded themselves into the belief that mechanical
trades (dirty jobs) are somehow devoid of education and skill and have
actively discouraged their children from having any interest in such
things.

This delusion of the PYVs (plastic yuppie vermin) is furthered by the
increasing complexity of cars and the thought that the grease monkeys
couldn't possibly understand anything about computers so they must just
be swapping parts until things magically start working.

It's only going to get worse too...

Pete C.

On Sat, 26 Nov 2005 15:52:36 GMT, "Pete C."
wrote:


Not entirely true, the few lucky people who have been able to find
honest, reliable mechanics do tend to speak highly of them.


Only those who have the sense to know the value of finding and keeping
a good mechanic (or any other tradesman/proffessional) There are fewer
of THEM out there than there are honest reliable mechanics.

It just wasn't fun any more after 25 years - and its gotten a whole
lot worse in the last 15 or more years.

Remember that the people bringing in the cars in the last 15 years or so
as you have noted, are the parents (or now their children) from the
generation that has deluded themselves into the belief that mechanical
trades (dirty jobs) are somehow devoid of education and skill and have
actively discouraged their children from having any interest in such
things.

This delusion of the PYVs (plastic yuppie vermin) is furthered by the
increasing complexity of cars and the thought that the grease monkeys
couldn't possibly understand anything about computers so they must just
be swapping parts until things magically start working.

And I got out of the mechanics trade and into the computer service
world - - -.

It's only going to get worse too...

That's what I decided 17 years ago. And I was right.

Now everybody's kid wants to be a computer tech instead of a mechanic
- and for the same reason kids wanted to be mechanics 40 years ago. 40
years ago the "gearheads" wanted to be mechanics to fool around with
their first love - the CAR.
Now the "computer nerds" want to be able to play with THEIR first love
- the Computer / Game console/ Whatever.
And they will work for almost nothing just to be able to do it. and
their method of repair??? "swapping parts until things magically start
working"

Time for a THIRD career?? (4th if you include teaching)

Pete C.

"Pete C." wrote:

Not entirely true, the few lucky people who have been able to find
honest, reliable mechanics do tend to speak highly of them.





Remember that the people bringing in the cars in the last 15 years or so
as you have noted, are the parents (or now their children) from the
generation that has deluded themselves into the belief that mechanical
trades (dirty jobs) are somehow devoid of education and skill and have
actively discouraged their children from having any interest in such
things.

This delusion of the PYVs (plastic yuppie vermin) is furthered by the
increasing complexity of cars and the thought that the grease monkeys
couldn't possibly understand anything about computers so they must just
be swapping parts until things magically start working.

It's only going to get worse too...

Pete C.


Seven or eight years ago the gas gauge quit on my dad's jeep. He
took it to the dealer. The changed the sending unit. Then they changed
the gauge. They had it over a week and still hadn't fixed it, so he paid
them over $400 to get it back. I took a look at it and found the problem
in 15 seconds. The lug on the ground wire to the sending unit had
snapped, and the wire was hanging down, in plain sight. A new lug took a
few minutes to install and it worked fine, till he traded it in on a new
car a few years later.
--
?

Michael A. Terrell
Central Florida

wrote:

On Sat, 26 Nov 2005 15:52:36 GMT, "Pete C."
wrote:

Not entirely true, the few lucky people who have been able to find
honest, reliable mechanics do tend to speak highly of them.


Only those who have the sense to know the value of finding and keeping
a good mechanic (or any other tradesman/proffessional) There are fewer
of THEM out there than there are honest reliable mechanics.


Its like the days when there were real TV shops. The techs knew what
they were doing, and went to every available factory school to keep up
with the new designs. Most people thought you just shoved tubes in till
the set worked, and that it was criminal to even want to make minimum
wage. They were rude, ignorant, and price shopped for the cheapest
service calls. Well, guess what? The cheapest service calls were the
fly by night operators who worked out of the trunk of their car, or in
one case, a dirty old hippie in a VW van that reeked of marijuana some.
It was rare to find a good customer who understood that it took time to
repair something, and some parts took time to find.

We had a "Customer" take us to small claims court because we charged
for an estimate. He claimed that his mechanic didn't charge for an
estimate, so we had no right to, either. He and the judge had big
smiles on their faces as they told my boss he was wrong. My boss plopped
a RCA CTC38 series chassis on the Judge's bench and said, Well, in that
case would you mind telling me what's wrong with this set? The judge
started yelling that he had no idea what was wrong so my boss asked, If
you can't tell by looking, how can we? We have to find the problem,
replace the part and make sure there are no other problems before we can
give you an accurate estimate. He won the case.



It just wasn't fun any more after 25 years - and its gotten a whole
lot worse in the last 15 or more years.

Remember that the people bringing in the cars in the last 15 years or so
as you have noted, are the parents (or now their children) from the
generation that has deluded themselves into the belief that mechanical
trades (dirty jobs) are somehow devoid of education and skill and have
actively discouraged their children from having any interest in such
things.

This delusion of the PYVs (plastic yuppie vermin) is furthered by the
increasing complexity of cars and the thought that the grease monkeys
couldn't possibly understand anything about computers so they must just
be swapping parts until things magically start working.

And I got out of the mechanics trade and into the computer service
world - - -.

It's only going to get worse too...

That's what I decided 17 years ago. And I was right.

Now everybody's kid wants to be a computer tech instead of a mechanic
- and for the same reason kids wanted to be mechanics 40 years ago. 40
years ago the "gearheads" wanted to be mechanics to fool around with
their first love - the CAR.
Now the "computer nerds" want to be able to play with THEIR first love
- the Computer / Game console/ Whatever.
And they will work for almost nothing just to be able to do it. and
their method of repair??? "swapping parts until things magically start
working"


I started computer repair on the old Commodore 64. A scope and good
soldering skills were a must. I built a test bed with ZIF sockets to
test the different chips so I could verify that they were bad, and to
test new chips when they arrived for wherever I could buy them. Now,
I'm old and disabled so I repair PCs as a hobby. I collect dead and half
stripped computers and build working systems from the parts. They are
given to the local "Vets helping Vets" program so they can be given to
disabled Veterans who can not afford to buy a computer. It gives me
something to do for a few hours a day, but I really miss building TV
stations and telemetry equipment for the aerospace industry.

Time for a THIRD career?? (4th if you include teaching)

Pete C.


--
?

Michael A. Terrell
Central Florida

Pete C. wrote:

Remember that the people bringing in the cars in the last 15 years or so
as you have noted, are the parents (or now their children) from the
generation that has deluded themselves into the belief that mechanical
trades (dirty jobs) are somehow devoid of education and skill and have
actively discouraged their children from having any interest in such
things.

I think you mean they are the "children (or now parents)"- this type of
mental dyslexia is disturbing to the meticulous reader.


This delusion of the PYVs (plastic yuppie vermin) is furthered by the
increasing complexity of cars and the thought that the grease monkeys
couldn't possibly understand anything about computers so they must just
be swapping parts until things magically start working.

I like that- PYV- good acronym- or "awesome" as the PYV say.

Ignoramus12834 wrote:
On Sat, 26 Nov 2005 15:52:36 GMT, Pete C. wrote:

This delusion of the PYVs (plastic yuppie vermin) is furthered by the
increasing complexity of cars and the thought that the grease monkeys
couldn't possibly understand anything about computers so they must just
be swapping parts until things magically start working.


They keep swapping parts because it makes them money.

A true story. A couple of years ago, a lightning struck a big tree in
our yard:

http://igor.chudov.com/tmp/lightning/

That also knocked out our central A/C.

So, I went in with a multimeter and tried tracing just where does not
signal go etc. I learned that the control board was sending proper
signal to the motor drive board, etc.

Then we called an A/C guy. He calls me at work and says stuff like
"the main board is probably knocked out and needs replacement", lets
replace this and that etc.

I asked him just what basis do you have for saying so. (because I knew
that it was bull****). He mumbled some nonsense. I decided not to hire
him, although I paid his visit fee. I did not feel like hiring someone
who is either incompetent or a crook. I called another A/C company and
explained them my findings etc.

He replaced the motor drive board, it was covered by warranty (but
labor was not), and everything works fine to date. Some other things
failed since, such as quick disconnect terminals fell apart on the
main contactor, but the control system is fine.

The moral of the story, they want replacing parts because it makes $$
for them.

i


The moral of the story is that you are PYV. All the electronic boards
are LRUs in the mechanical trades and there is no way that repair could
be cost effective any other way, parts are way below labor costs. In the
case of a lightning strike where one board has failed, it is good
practice to yank *all* of them and be done with it. You are getting
*new* boards at reasonable markup, you pay a single labor charge, and
there is no possibility of less than a durable fix or additional damage
being done due to faulty drive. I can see the HVAC tech breaking out the
oxy-acetylene torch to solder components...too funny.

Fred Bloggs wrote:

Pete C. wrote:

Remember that the people bringing in the cars in the last 15 years or so
as you have noted, are the parents (or now their children) from the
generation that has deluded themselves into the belief that mechanical
trades (dirty jobs) are somehow devoid of education and skill and have
actively discouraged their children from having any interest in such
things.

I think you mean they are the "children (or now parents)"- this type of
mental dyslexia is disturbing to the meticulous reader.

No, I meant it in the order it was in. The PYV parents came first 15 or
so years ago, followed later by the children of the PYVs once they were
old enough to have cars needing repairing.



This delusion of the PYVs (plastic yuppie vermin) is furthered by the
increasing complexity of cars and the thought that the grease monkeys
couldn't possibly understand anything about computers so they must just
be swapping parts until things magically start working.

I like that- PYV- good acronym- or "awesome" as the PYV say.

It's quick, descriptive and accurate.

Pete C.

On Sun, 27 Nov 2005 14:32:08 GMT, "Michael A. Terrell"
wrote:

"Pete C." wrote:

Not entirely true, the few lucky people who have been able to find
honest, reliable mechanics do tend to speak highly of them.





Remember that the people bringing in the cars in the last 15 years or so
as you have noted, are the parents (or now their children) from the
generation that has deluded themselves into the belief that mechanical
trades (dirty jobs) are somehow devoid of education and skill and have
actively discouraged their children from having any interest in such
things.

This delusion of the PYVs (plastic yuppie vermin) is furthered by the
increasing complexity of cars and the thought that the grease monkeys
couldn't possibly understand anything about computers so they must just
be swapping parts until things magically start working.

It's only going to get worse too...

Pete C.


Seven or eight years ago the gas gauge quit on my dad's jeep. He
took it to the dealer. The changed the sending unit. Then they changed
the gauge. They had it over a week and still hadn't fixed it, so he paid
them over $400 to get it back. I took a look at it and found the problem
in 15 seconds. The lug on the ground wire to the sending unit had
snapped, and the wire was hanging down, in plain sight. A new lug took a
few minutes to install and it worked fine, till he traded it in on a new
car a few years later.

Shrug...I spent $65 to have my truck run though the computer
diagnostics. They couldnt find the problem, suggested some high dollar
repairs..shotgun approach.

I replaced the badly worn distro cap and the rotor. Ran fine after
than.

Im starting to think that there are more button pushers than actual
tradesmen in auto mechanics.

Gunner

"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner

I had a mid-90's Chevy S-10 with antilock brakes. One day, the brakes
made a funny sound and the service light came on. I noticed that the
brakes were not behaving properly.

I took the truck in for "Mr. Goodwrench" to take a look. They told me
that I would need a new antilock computer and the cost was something on
the order of $1000. I told them to forget it.

I limped the truck home and later, curiosity got the better of me. I
jacked up the truck so that the front wheels could spin, and then I went
hunting for wheel rotation sensors. Connecting my scope, I could see a
nice, clean sine wave coming off the front right wheel. The waveform
from the front left wheel, however, had a a very irregular shape that
was much lower in amplitude.

I purchased a new rotation sensor for $75 bucks, pulled the wheel and
brake disk, and installed it. Everything worked like a champ after that.

It appeared that the old sensor had been struck by rock, and the core of
the sense coil had probably been fractured. I was left to wonder how it
is that, without the benefit of factory training, documentation, or
diagnostic equipment I could troubleshoot and repair the problem when
the dealership could not....

Michael A. Terrell wrote:

"Pete C." wrote:

Not entirely true, the few lucky people who have been able to find
honest, reliable mechanics do tend to speak highly of them.





Remember that the people bringing in the cars in the last 15 years or so
as you have noted, are the parents (or now their children) from the
generation that has deluded themselves into the belief that mechanical
trades (dirty jobs) are somehow devoid of education and skill and have
actively discouraged their children from having any interest in such
things.

This delusion of the PYVs (plastic yuppie vermin) is furthered by the
increasing complexity of cars and the thought that the grease monkeys
couldn't possibly understand anything about computers so they must just
be swapping parts until things magically start working.

It's only going to get worse too...

Pete C.



Seven or eight years ago the gas gauge quit on my dad's jeep. He
took it to the dealer. The changed the sending unit. Then they changed
the gauge. They had it over a week and still hadn't fixed it, so he paid
them over $400 to get it back. I took a look at it and found the problem
in 15 seconds. The lug on the ground wire to the sending unit had
snapped, and the wire was hanging down, in plain sight. A new lug took a
few minutes to install and it worked fine, till he traded it in on a new
car a few years later.

"H. P. Friedrichs" wrote:

I had a mid-90's Chevy S-10 with antilock brakes. One day, the brakes
made a funny sound and the service light came on. I noticed that the
brakes were not behaving properly.

I took the truck in for "Mr. Goodwrench" to take a look. They told me
that I would need a new antilock computer and the cost was something on
the order of $1000. I told them to forget it.

I limped the truck home and later, curiosity got the better of me. I
jacked up the truck so that the front wheels could spin, and then I went
hunting for wheel rotation sensors. Connecting my scope, I could see a
nice, clean sine wave coming off the front right wheel. The waveform
from the front left wheel, however, had a a very irregular shape that
was much lower in amplitude.

I purchased a new rotation sensor for $75 bucks, pulled the wheel and
brake disk, and installed it. Everything worked like a champ after that.

It appeared that the old sensor had been struck by rock, and the core of
the sense coil had probably been fractured. I was left to wonder how it
is that, without the benefit of factory training, documentation, or
diagnostic equipment I could troubleshoot and repair the problem when
the dealership could not....

Michael A. Terrell wrote:


That is why for the few things on my truck that I don't have the
facilities to do myself and can't justify buying new tools, when I take
it to the dealer for service I give them a specific set of instructions
on what to do and clear warning that they are *not* to attempt any
diagnosis or deviate from the exact work order I give them.

Pete C.

In article ,
lid says...

Once my wife's car developed some sort of a fault light. Since I had
this code reader, I determined that the problem was with the fuel tank
and after googling, it turned out that her fuel tank cap was not fully
screwed in. Properly tightening it took care of the problem. Had I
not owned it, it would be a whole evening ruined, at least $50-100
paid to a car mechanic (that's assuming an honest car mechanic who
would not ask for unnecessary repairs), etc.

An honest mechanic would first tell you to tighten the fuel cap
before they look at it and charge nothing for the advice. This is
a *very* common proglem; BTDT. Here, most of the bigger auto parts
stores will read out the computer as a free service. They won't
reset the codes, but will tell you what the computer "thinks".

OTOH, my '93 Eagle Vision had an intermittent in the flywheel
sensor (no RPMs - no ignition/fuel) that didn't show up on the
computer until it failed with the computer attached. The shop
drove the thing for a week before the failure occured.

--
Keith

On Sun, 27 Nov 2005 18:29:30 GMT, Gunner Asch
wrote:

On Sun, 27 Nov 2005 14:32:08 GMT, "Michael A. Terrell"
wrote:

"Pete C." wrote:

Not entirely true, the few lucky people who have been able to find
honest, reliable mechanics do tend to speak highly of them.





Remember that the people bringing in the cars in the last 15 years or so
as you have noted, are the parents (or now their children) from the
generation that has deluded themselves into the belief that mechanical
trades (dirty jobs) are somehow devoid of education and skill and have
actively discouraged their children from having any interest in such
things.

This delusion of the PYVs (plastic yuppie vermin) is furthered by the
increasing complexity of cars and the thought that the grease monkeys
couldn't possibly understand anything about computers so they must just
be swapping parts until things magically start working.

It's only going to get worse too...

Pete C.


Seven or eight years ago the gas gauge quit on my dad's jeep. He
took it to the dealer. The changed the sending unit. Then they changed
the gauge. They had it over a week and still hadn't fixed it, so he paid
them over $400 to get it back. I took a look at it and found the problem
in 15 seconds. The lug on the ground wire to the sending unit had
snapped, and the wire was hanging down, in plain sight. A new lug took a
few minutes to install and it worked fine, till he traded it in on a new
car a few years later.

Shrug...I spent $65 to have my truck run though the computer
diagnostics. They couldnt find the problem, suggested some high dollar
repairs..shotgun approach.

I replaced the badly worn distro cap and the rotor. Ran fine after
than.

Im starting to think that there are more button pushers than actual
tradesmen in auto mechanics.

Gunner


And you need to ask why??????
Anyone with half a brain got out of the business 15 or 20 years ago.
ANd not too many with half a brain or more are getting into the
business over the last 20 years.

When I started in the late sixties, it was the lowest paid trade - bar
none.
When I taught the trade in the seventies, the attitude at the schools
was "he's too dumb to make a scientist, plumber, electrician, or
machinist out of - and too smart to be a lawyer, so we'll put him in
Auto Mechanics.

So I had to teach them electrical, plumbing, physics, machining, math,
and all the rest to make mechanics out of them.

"Pax Americana is a philosophy. Hardly an empire.
Making sure other people play nice and dont kill each other (and us)
off in job lots is hardly empire building, particularly when you give
them self determination under "play nice" rules.

Think of it as having your older brother knock the **** out of you
for torturing the cat." Gunner

In article ,
"H. P. Friedrichs" wrote:

[...]

I was left to wonder how it
is that, without the benefit of factory training, documentation, or
diagnostic equipment I could troubleshoot and repair the problem when
the dealership could not....

Depends heavily on the tech who looks at it. I was handed a truck a
couple of weeks ago that someone had spent all day trying to
troubleshoot. No cruise control, no Jake brakes. He'd thrashed around
for eight hours, running diagnostics, checking sensors, even popped the
valve covers to check the brake solenoids.
I found the broken clutch pedal return spring in less than a minute.
$12 part, five minutes to install.

--
B.B. --I am not a goat! thegoat4 at airmail dot net

On Mon, 28 Nov 2005 19:50:03 GMT, Ignoramus4324
wrote:

On Sun, 27 Nov 2005 18:27:24 -0700, H. P. Friedrichs wrote:
It appeared that the old sensor had been struck by rock, and the core of
the sense coil had probably been fractured. I was left to wonder how it
is that, without the benefit of factory training, documentation, or
diagnostic equipment I could troubleshoot and repair the problem when
the dealership could not....

It is not true that you did not have diagnostic equipment, you had a
scope. You also had enough training to figure out where to look.

As for documentation, everyone would benefit from owning proper repair
manuals.

What these techs do is, for the most part, not magic, they follow a
[well designed] procedure -- except when the dishonest ones suggest
unnecessary repairs, as in proposing to start swapping one part after
another.

i

In many cases these mechanics are not so much dishonest as ignorant.
They just plain do NOT know how to troubleshoot.
The ones that have the manual, and know how to read it (that is an art
in itself - particularly with FORD Manuals) they blindly follow the
pinpoint tests - which can send you in 15 interlocking circles at the
same time if you do not use your PDT (Primary Diagnostic Tool)
(Otherwize known as the brain God gave you). Blindly following the
manual can cause you to replace many parts that are not part of the
problem.

In order to effectively troubleshoot today's systems, you MUST have an
understanding of how it is SUPPOSED to work, so when it doesn't, you
have a clue as to why.

On Mon, 28 Nov 2005 19:50:03 +0000, Ignoramus4324 wrote:

On Sun, 27 Nov 2005 18:27:24 -0700, H. P. Friedrichs wrote:
It appeared that the old sensor had been struck by rock, and the core of
the sense coil had probably been fractured. I was left to wonder how it
is that, without the benefit of factory training, documentation, or
diagnostic equipment I could troubleshoot and repair the problem when
the dealership could not....

It is not true that you did not have diagnostic equipment, you had a
scope. You also had enough training to figure out where to look.

As for documentation, everyone would benefit from owning proper repair
manuals.

What these techs do is, for the most part, not magic, they follow a
[well designed] procedure -- except when the dishonest ones suggest
unnecessary repairs, as in proposing to start swapping one part after
another.


Yeah, I went to Midas for a "$39.99" muffler. When I finally got the
car back, the bill was over $400.00. I should have sued the *******s.

Don't ever go to Midas, and tell your friends, relatives, and what the
heck, people on the street: Don't go to Midas - they're thieves.

Thanks,
Rich

Ed Huntress wrote:
"Too_Many_Tools" wrote in message
oups.com...
I am the "lucky" owner of a number of older UPSes.

So what can a person build out of these?

The batteries are for the most part dead but the remainder of the
components seem to be in good condition.

Any suggestions?

Thanks

TMT

If you can get your hands on a copy of the 2005 ARRL Handbook, there are
several suggestions in there (radio-related, but you can improvise from
them), and some information about UPS's.

One is a charger for 12V storage batteries in general, including car
batteries. Another is an emergency power supply (you can just run two wires
to your car battery, or a bank of deep-discharge batteries wired in parallel
if you're so inclined). Depending on the model you have, you can get 160 W
to over 300 W of 120 VAC and/or 12VDC from them.

Mine (an APC Back-UPS 600) is now wired to an old car battery. It will run
my computer for a lot longer than the old gel-cell that came with it. Since
we're on the end of a power transmission line, it gets a fair amount of use.

--
Ed Huntress

Ed from Ed I just picked up a apc bk500. I charged it most of the night
and the voltage only shows 98 volt on battery. The instructions on the
internet show some sort of cd disc for windows which I do not have with
a good battery can I just use it as it is for a usp for the computer.
no alarm led lights on and it appears to be working fine thanks Ed

"Ed ke6bnl" wrote in message
oups.com...

Ed Huntress wrote:
"Too_Many_Tools" wrote in message
oups.com...
I am the "lucky" owner of a number of older UPSes.

So what can a person build out of these?

The batteries are for the most part dead but the remainder of the
components seem to be in good condition.

Any suggestions?

Thanks

TMT

If you can get your hands on a copy of the 2005 ARRL Handbook, there are
several suggestions in there (radio-related, but you can improvise from
them), and some information about UPS's.

One is a charger for 12V storage batteries in general, including car
batteries. Another is an emergency power supply (you can just run two
wires
to your car battery, or a bank of deep-discharge batteries wired in
parallel
if you're so inclined). Depending on the model you have, you can get 160
W
to over 300 W of 120 VAC and/or 12VDC from them.

Mine (an APC Back-UPS 600) is now wired to an old car battery. It will
run
my computer for a lot longer than the old gel-cell that came with it.
Since
we're on the end of a power transmission line, it gets a fair amount of
use.

--
Ed Huntress

Ed from Ed I just picked up a apc bk500. I charged it most of the night
and the voltage only shows 98 volt on battery. The instructions on the
internet show some sort of cd disc for windows which I do not have with
a good battery can I just use it as it is for a usp for the computer.
no alarm led lights on and it appears to be working fine thanks Ed

I'm not aware of the inner workings of these things, Ed, nor have I put an
AC voltmeter on the output, running off the car battery, to see what actual
voltage I'm getting. The computer runs fine off of it but now you have my
curiosity going.

--
Ed Huntress

Ed from Ed I just picked up a apc bk500. I charged it most of the night
and the voltage only shows 98 volt on battery. The instructions on the
internet show some sort of cd disc for windows which I do not have with
a good battery can I just use it as it is for a usp for the computer.
no alarm led lights on and it appears to be working fine thanks Ed

I'm not aware of the inner workings of these things, Ed, nor have I put an
AC voltmeter on the output, running off the car battery, to see what actual
voltage I'm getting. The computer runs fine off of it but now you have my
curiosity going.

It might be worth re-checking the AC output voltage using a voltmeter
which reads "true RMS". Most inexpensive voltmeters actually read the
peak voltage, and display an RMS value calculated based on the
assumption that the waveform is sinusoidal.

A lot of backup power supplies use inverters that create a distinctly
non-sinusoidal waveform... it's sometimes a square wave, and sometimes
a "stepped" waveform which crudely approximates a sinusoid.

It's entirely possible that the APC BK500 creates a non-sinusoidal
waveform, whose RMS value is close to the nominal 120 VAC, but whose
peak voltage is lower than that of a true sinusoid having 120 VAC RMS.
This could cause most inexpensive voltmeters to read a value that's
too low.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

The APC BK500 has a step Output waveform that would be no problem for a
computer and monitor.
MGE UPS systems are a sinewave

"Dave Platt" wrote in message
...
Ed from Ed I just picked up a apc bk500. I charged it most of the night
and the voltage only shows 98 volt on battery. The instructions on the
internet show some sort of cd disc for windows which I do not have with
a good battery can I just use it as it is for a usp for the computer.
no alarm led lights on and it appears to be working fine thanks Ed

I'm not aware of the inner workings of these things, Ed, nor have I put an
AC voltmeter on the output, running off the car battery, to see what
actual
voltage I'm getting. The computer runs fine off of it but now you have my
curiosity going.

It might be worth re-checking the AC output voltage using a voltmeter
which reads "true RMS". Most inexpensive voltmeters actually read the
peak voltage, and display an RMS value calculated based on the
assumption that the waveform is sinusoidal.

A lot of backup power supplies use inverters that create a distinctly
non-sinusoidal waveform... it's sometimes a square wave, and sometimes
a "stepped" waveform which crudely approximates a sinusoid.

It's entirely possible that the APC BK500 creates a non-sinusoidal
waveform, whose RMS value is close to the nominal 120 VAC, but whose
peak voltage is lower than that of a true sinusoid having 120 VAC RMS.
This could cause most inexpensive voltmeters to read a value that's
too low.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
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