On Aug 17, 6:07 pm, CJT wrote:
Tony wrote:
Chris we are not going any way so I am not going to comment
however? there is no such thing in AC circuit as positive
and negative the on three phase system or single phase,
the phases are out of phase by 90 degree
that is it! no positive or negative
just about 6-7 months ago I had job replacing 25 hp Refrigeration
compressor that runs on 480 three phase and guess what
one phase was neutral, amazing isn't and you telling me
neutral is not carrying current I afraid you will need eat few more Winnies
by have nice day Tony

May I suggest you read this: ?

http://en.wikipedia.org/wiki/Split_phase


That must have changed popular opinion.

Thanks

"Thomas Horne" wrote in message
...
Tony wrote:
"Chris Friesen" wrote in message
...
Tony wrote:

look easiest way to solve mystery is hook up one light bulb
and measure the current on both wires and you will find
that both weirs have same current flow, that's easy enough,
In a 3-wire circuit you have two hots and a neutral. If you put a light
bulb between each of the hots and the neutral, there will be no current
flow in the neutral.


to above
You right because you have just made artificial neutral
your center tap between two light bulbs is acting same as
perhaps if you have tied to transformer with center tap.
Look in any system if you have two wires going to a load each
wire will carry same amount of current it does not matter if is
120 or 220 or 480 if is light to be light or motor to be run both
wire/legs will carry identical current regardless if is neutral or hot,
the current is equal in both legs, in three phase system current
will depend on the balance of electrical components to be powered
and voltage supplied this are basics and they do not change

Tony



O yes it will and twice the hot legs, as I siad try and do little
expirement on your onw and find out for your self
Tony

In essence, the current flows up one hot, through the bulb, through the
other bulb, and back down the other hot. (It's like one hot is
positive, the other is negative, and the neutral is zero.)

The neutral is only needed for the case where the load on each of the
hot legs is not equal.

Chris



Tony
You are off your soundings there bud. In case your not nautically
inclined that means you are out of your depth. If you wire two sixty watt
bulbs in series across a two forty volt circuit they will burn just fine.
Now connect a neutral to the connection that is between the two bulbs and
if the bulbs are truly identical then no current will flow on the neutral.

Here's a little experiment for you to try. You can build an Edison
circuit from two twelve volt batteries and two twelve volt lamps. Wire
them all in series. The two twelve volt lights will light just fine.
connect a volt meter across the connection between the lights and the
connection between the batteries. It will measure six volts. Now change
the leads and settings on your multimeter from voltage to current and
measure across the same two points. Applying the ammeter as a neutral
conductor will not change the current significantly.
The only current flowing will be caused by the slight differences in
manufacture between the two lights and the two batteries.
--
Tom Horne

"Thomas Horne" wrote in message
...
"Chris Friesen" wrote
In a 3-wire circuit you have two hots and a neutral. If you put a
light bulb between each of the hots and the neutral, there will be no
current flow in the neutral.
O yes it will and twice the hot legs, as I siad try and do little
expirement on your onw and find out for your self
Tony
"Chris Friesen" wrote in message
...
I honestly can't tell if you're a troll or not.

If the neutral could carry twice the current of the hots in normal use,
then it would have to be a larger conductor than the hots.

In reality, the neutral in a feeder line is often *undersized* relative
to the hots. This is because it only carries the difference between the
two hots, and if you have balanced loads or 240V loads there is no
current in the neutral.

If that isn't enough of an explanation, I give up. This thread has gone
long enough. Please don't do your own wiring.

Chris


Tony wrote:
Chris we are not going any way so I am not going to comment
however? there is no such thing in AC circuit as positive
and negative the on three phase system or single phase,
the phases are out of phase by 90 degree
that is it! no positive or negative
just about 6-7 months ago I had job replacing 25 hp Refrigeration
compressor that runs on 480 three phase and guess what
one phase was neutral, amazing isn't and you telling me
neutral is not carrying current I afraid you will need eat few more
Winnies by have nice day Tony


Tony
If you think all grounded current carrying conductors are neutrals then
you are inadequately trained. A corner grounded Delta transformer set,
such as the one that probably supplied your refrigeration compressor,
cannot supply a neutral. The only time phases will be ninety degrees out
of phase is in a Scot T transformer arrangement.

The two hundred and forty volt, single phase, transformers that are used
to supply homes in North American practice are supplied from a single
phase on the primary side. How can a transformer with only two windings
produce a phase difference across it's output winding?


Transformer that is use has center tap, the centre tap
does two things it serve as neutral and split the phase
at same time 90 degree apart
Tony




If you have worked with buck boost transformers you know that a single
phase transformer can be tapped on it's secondary side to supply several
different voltages and although it is rarely done those different voltages
can be from the same transformer secondary. I could ground any one of the
taps as long as I ground only one without effecting the voltage output
available from each portion of the secondary winding. If it produces
several voltages on it's output does that make it multi phase? Voltage is
usually measured to ground because it is that voltage the insulation must
successfully withstand. If you measure the outputs against each other
using an oscilloscope you will find that the wave forms are identical in
the horizontal or time domain and that they differ only in their amplitude
as an expression of their voltage.
--
Tom Horne

In article IeZxi.579$jy6.298@trnddc01, "Tony" wrote:



Transformer that is use has center tap, the centre tap
does two things it serve as neutral and split the phase
at same time 90 degree apart

Nope -- 180 degrees.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

"Doug Miller" wrote in message
...
In article , "SRN"
wrote:

"George" wrote in message
m...

.. On a single phase system the legs are 180 degrees out of phase
with each other.

When you say this you need to add ", referenced to ground (neutral)"

No, you don't. The statement refers solely to the phase difference between
the
two hot legs, which has absolutely nothing to do with either's potential
difference from neutral.

You're wrong.......if the two hot legs were 180° apart, they would cancel
each other.
There would be 2 currents in 2 directions cancelling, or partially canceling
each other. This happens
in a center-tapped neutral, but not with the hot legs. Dis-regarding the
neutral connection on std. 120/240V
center-tapped service, the 2 hot legs are simply the ends of the secondary
transformer coil with a 240V RMS sine wave.
To be 180° out of phase you need two sine waves - where is the other one?
(Remember, we are disregarding neutral - per your insistance)..........

On Aug 13, 10:21 pm, kpg wrote:
Hi all. A simple electrical question (I hope).

I have a clamp on amp meter and I'm interested in seeing how much
current
is used at various loads by the feeder line running to my remote
garage.

The feeder is has 2 hots and 1 neutral going to a sub panel that
divides it
into several 110 circuits.

I know that the current on the neutral will be the difference between
the current on
the two hots (less any stray current lost to the grounding rod), but
I'm interested in
knowing the 'total' amps of the 220 circuit.

I'm thinking I could measure the current on one hot, then on the other
hot, and add
the two values together. What I would like to do is install a
permanent meter but
now I'm thinking that I need two, one for each hot. If I try to
measure the current
by passing both hots through the 'clamp', since they are 180 degrees
out of phase,
won't they cancel each other out (and I would end up with the
difference of the
two like on the netural)?

So my long winded question is this - how can I use a single 'clamp-on'
style meter
to measure current on a 220vac circuit?

Thanks.

There is a lot of mis-information in the other posts. The answer to
your question is you can use one meter. You need to pass both hot
leads through the clamp on meter, but one hot lead has to pass through
in the "reverse direction". This may be hard to arrange with heavy
wires.

Now the meter will give an indication of the 110V current. If you
have 10 Amp 110V load on one hot lead the meter will read 10 Amps. If
you have a 10 Amp 220 load, the meter will read 20 because you are
using 10 Amps in both hot leads. If you have a 10 Amp 110 V load on
the other hot lead, the meter will read 10 Amps.

Have fun
Mark

According to Tony :

"Chris Friesen" wrote in message
...
Tony wrote:

look easiest way to solve mystery is hook up one light bulb
and measure the current on both wires and you will find
that both weirs have same current flow, that's easy enough,

In a 3-wire circuit you have two hots and a neutral. If you put a light
bulb between each of the hots and the neutral, there will be no current
flow in the neutral.

O yes it will and twice the hot legs, as I siad try and do little
expirement on your onw and find out for your self

Every Canadian house built within the past 40 years, with the exception
of the last two, is performing this "experiment" _every_ day. Because
our kitchen counter outlets are ALL wired this way.

[This is also true of many American homes}

The neutral carries the difference current. It doesn't add.

If it added, half our homes would have burned down by now.
--
Chris Lewis,

Age and Treachery will Triumph over Youth and Skill
It's not just anyone who gets a Starship Cruiser class named after them.