Hi,
Does anyone know of a way to measure the current being used on a
single circuit breaker from just one of the wall outlets on that
circuit?

ie; I want to be able to plug something in anywhere in the house and
be able to tell from there how many amps the circuit breaker is using.
thanks

wrote:

Does anyone know of a way to measure the current being used on a
single circuit breaker from just one of the wall outlets on that
circuit?

Nope. You need a clamp-on ammeter around the wire going to the breaker.

Chris

On Tue, 20 Feb 2007 14:42:07 -0600, Chris Friesen
wrote:

wrote:

Does anyone know of a way to measure the current being used on a
single circuit breaker from just one of the wall outlets on that
circuit?

Nope. You need a clamp-on ammeter around the wire going to the breaker.

What are you plugging into the outlet? The easiest method is just
estimate it from the power rating of the device you are plugging in.
There should be a Wattage (Power) marking somewhere on a nameplate on
the device. The current will be approximately = P/120 (assuming
your voltage is 120V). Example - If you are running a 1200 W space
heater, that would take 10A.

If it is a motorized appliance, such as a vacuum cleaner, it will have
a power factor of less than one, which means it will draw slightly
more current than it actually consumes in measurable output power.

If it is a heavy duty appliance like an air-conditioner, the startup
currrent may be high (almost double) during the fraction of a second
that it is coming up to spead.

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

Does anyone know of a way to measure the current being used on a
single circuit breaker from just one of the wall outlets on that
circuit?

Nope. You need a clamp-on ammeter around the wire going to the breaker.

Ummm, the circuit breaker is fed by a bus ... that you cannot clamp around.

On Tue, 20 Feb 2007 16:59:14 -0500, "Charles Schuler"
wrote:


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

Does anyone know of a way to measure the current being used on a
single circuit breaker from just one of the wall outlets on that
circuit?

Nope. You need a clamp-on ammeter around the wire going to the breaker.

Ummm, the circuit breaker is fed by a bus ... that you cannot clamp around.


Looks like someone can't tell the difference between "to" and "from".
That reminds me of the numerous people who kept confusing "inputs" and
"outputs" on audio/video equipment.
--
Mark Lloyd
http://notstupid.laughingsquid.com

"Unlike biological evolution. 'intelligent design' is
not a genuine scientific theory and, therefore, has
no place in the curriculum of our nation's public
school classes." -- Ted Kennedy

On Tue, 20 Feb 2007 16:59:14 -0500, "Charles Schuler"
wrote:


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

Does anyone know of a way to measure the current being used on a
single circuit breaker from just one of the wall outlets on that
circuit?

Nope. You need a clamp-on ammeter around the wire going to the breaker.

Ummm, the circuit breaker is fed by a bus ... that you cannot clamp around.



Hummm, but the buss is fed by a main and that main is fed by wire that
you can clamp around.

Hummm, but the buss is fed by a main and that main is fed by wire that
you can clamp around.

Not in any power panel that I have seen recently.

Charles Schuler wrote:

Hummm, but the buss is fed by a main and that main is fed by wire that
you can clamp around.


Not in any power panel that I have seen recently.




I think he meant that the bus was fed through the main breaker, which IS
fed by a wire, usually coming from the meter base.

But, to make a meaningful measurement using that wire he'd have to
switch off ALL the other breakers on that feed's side of the panel. Not
a very practical solution, is it? G

Jeff

--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
The speed of light is 1.8*10^12 furlongs per fortnight.

On Tue, 20 Feb 2007 17:35:03 -0500, "Charles Schuler"
wrote:



Hummm, but the buss is fed by a main and that main is fed by wire that
you can clamp around.

Not in any power panel that I have seen recently.

OTOH, since he's wondering about the power used
on one circut, many people might suggest
clamping the ammeter on the wire that feeds
that circut. You know, where it comes off the
breaker. I know that sounds crazy, but it might
work anyway.

Why not?

--
Steve Barker


"Charles Schuler" wrote in message
...


Hummm, but the buss is fed by a main and that main is fed by wire that
you can clamp around.

Not in any power panel that I have seen recently.

Charles Schuler wrote:
"Chris Friesen" wrote

Nope. You need a clamp-on ammeter around the wire going to the breaker.

Ummm, the circuit breaker is fed by a bus ... that you cannot clamp around.

The circuit has one wire attached to the breaker, and the other goes to
the neutral bus (assuming a 120V circuit). You can put a meter around
the wire that is connected to the breaker.

Are you seriously arguing about wether a wire goes "to" or "from" a
breaker? In an AC circuit where current flows both ways?

Chris

On Tue, 20 Feb 2007 17:47:10 -0600, Chris Friesen
wrote:

Charles Schuler wrote:
"Chris Friesen" wrote

Nope. You need a clamp-on ammeter around the wire going to the breaker.

Ummm, the circuit breaker is fed by a bus ... that you cannot clamp around.

The circuit has one wire attached to the breaker, and the other goes to
the neutral bus (assuming a 120V circuit). You can put a meter around
the wire that is connected to the breaker.

Are you seriously arguing about wether a wire goes "to" or "from" a
breaker? In an AC circuit where current flows both ways?


Consider that while current does flow both ways (or more correctly, is
ALTERNATING direction), POWER goes one way. "Direction" is useful
there.

Chris
--
Mark Lloyd
http://notstupid.laughingsquid.com

"Unlike biological evolution. 'intelligent design' is
not a genuine scientific theory and, therefore, has
no place in the curriculum of our nation's public
school classes." -- Ted Kennedy

Mark Lloyd wrote:

Consider that while current does flow both ways (or more correctly, is
ALTERNATING direction), POWER goes one way. "Direction" is useful
there.

How do you figure that? Power is a scalar quantity given by I^2*R.

Power dissipated by a load is always positive no matter which direction
the current flows through the load.

Chris

wrote in message
oups.com...
Hi,
Does anyone know of a way to measure the current being used on a
single circuit breaker from just one of the wall outlets on that
circuit?

ie; I want to be able to plug something in anywhere in the house and
be able to tell from there how many amps the circuit breaker is using.
thanks

There is usually a black wire connected to the circuit breaker. If you can
clamp around that wire with the appropriate ammeter (Google clamp-on
ammeter) you can measure the current in that circuit.

What are you trying to accomplish?

wrote in message
oups.com...
Hi,
Does anyone know of a way to measure the current being used on a
single circuit breaker from just one of the wall outlets on that
circuit?

ie; I want to be able to plug something in anywhere in the house and
be able to tell from there how many amps the circuit breaker is using.
thanks



I have an adaptor for my ammeter that I can plug into an ordinary wall
receptacle. It has a loop on it to clamp around and I can plug an appliance
into it to see what the load is for that appliance. I think Amprobe makes
it.


John Grabowski
http://www.mrelectrician.tv

On Tue, 20 Feb 2007 18:30:25 -0500, "John Grabowski"
wrote:


wrote in message
roups.com...
Hi,
Does anyone know of a way to measure the current being used on a
single circuit breaker from just one of the wall outlets on that
circuit?

ie; I want to be able to plug something in anywhere in the house and
be able to tell from there how many amps the circuit breaker is using.
thanks



I have an adaptor for my ammeter that I can plug into an ordinary wall
receptacle. It has a loop on it to clamp around and I can plug an appliance
into it to see what the load is for that appliance. I think Amprobe makes
it.


John Grabowski
http://www.mrelectrician.tv

I'm using a Kill-A-Watt meter for that now, but previously I had a VOM
attachment for that. I made it from a remote control cord (just a
switch at one end) with the switch removed and replaced with banana
plugs.
--
Mark Lloyd
http://notstupid.laughingsquid.com

"Unlike biological evolution. 'intelligent design' is
not a genuine scientific theory and, therefore, has
no place in the curriculum of our nation's public
school classes." -- Ted Kennedy