How To Calculate KWH With CT Around 1 Conductor On Parallel Feed

[5 S electric]

We Have an Emon Meter on one of or buildings. It has 800 amp cts. The cts wont allow us to get around all 3 conductors on a parallel run. The MDP is to small and the way the contractor ran the wires in wont allows us to get around all of the conductors. Should i just multiply the amps and kwh x 3?

 

[GoldDigger]

We Have an Emon Meter on one of or buildings. It has 800 amp cts. The cts wont allow us to get around all 3 conductors on a parallel run. The MDP is to small and the way the contractor ran the wires in wont allows us to get around all of the conductors. Should i just multiply the amps and kwh x 3?

The current could easily vary by as much as 5% in a parallel run, so picking one and multiplying by three will not be very accurate. But if you are most interested in comparative numbers rather than absolute numbers it might work. You would get more accuracy by putting it on two of the three wires and multiplying by 1.5.
Depending on the wire sizes, you could add a CT box in which you took all three runs down to a larger single copper conductor and back out to three, then put the CT on the single piece.
If the conductors are Al, you could pigtail the last few feet with Cu to get them to fit into the CT.
I do not see a simple solution.
You could also use three CTs and parallel them into the meter.

 

[5 S electric]

The current could easily vary by as much as 5% in a parallel run, so picking one and multiplying by three will not be very accurate. But if you are most interested in comparative numbers rather than absolute numbers it might work. You would get more accuracy by putting it on two of the three wires and multiplying by 1.5.
Depending on the wire sizes, you could add a CT box in which you took all three runs down to a larger single copper conductor and back out to three, ten put the CT on the single piece.
If the conductors are Al, you could pigtail the last few feet with Cu to get them to fit into the CT.

The problem is there is no room for the CT to go around all conductors. I asked EMON if the sold a Flexible CT and they don't. They also say that the EMON meter has to match the CTs they send.

 

[Jraef]

The problem is there is no room for the CT to go around all conductors. I asked EMON if the sold a Flexible CT and they don't. They also say that the EMON meter has to match the CTs they send.

Read this:
http://www.ccontrolsys.com/w/Measuring_Parallel_Conductors
It delves into what GoldDigger mentioned, but provides you with some alternatives. Note however that if you go the route you asked about, which is at the end of the story here, your meter will need the ability to be told that it must perform the calculations, otherwise the readings you get will be useless.

It's sad that EMON left you high and dry on this, I thought they were better than that.

 

[Phil Corso]

5 S Electric,

A relatively easy test to determine the degree of conductor-current imbalance is to measure the sending-end and receiving-end ph-ph voltage triangles!

Regards, Phil Corso

 

[Carultch]

The current could easily vary by as much as 5% in a parallel run, so picking one and multiplying by three will not be very accurate. But if you are most interested in comparative numbers rather than absolute numbers it might work. You would get more accuracy by putting it on two of the three wires and multiplying by 1.5.
Depending on the wire sizes, you could add a CT box in which you took all three runs down to a larger single copper conductor and back out to three, then put the CT on the single piece.
If the conductors are Al, you could pigtail the last few feet with Cu to get them to fit into the CT.
I do not see a simple solution.
You could also use three CTs and parallel them into the meter.

I don't think there exists any single wire that can carry 800A.