Voltage reading on CT "B" only for single phase

- Believe I installed correctly according to these instructions for single phase

- Single phase residential

- CT "A" and CT "B" are clamped on to the same load wire (for testing) (HVAC)

- Moved CT "A" wiring to "B" and "B" to "A"

- No change.. Only "B" showing voltage


Any thoughts.

I do question my install, I tied "UA" and "UC" together, then "Line" into "UB". However, was I supposed to tie all 3 together (UA + UC + UB) somehow?





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Hi:

1 please do  not post your SN in the public forum(I have help you to hide the SN in the pic this time)

2 Yes, it is a better method to test the meter using all three phases to measure the same load and check whether the measurement result is nearly the same.

(clamp all three phase CT on the same wire and power Ua, Ub, and Uc by the same voltage input)

This specific step is described here 

https://www.iammeter.com/newsshow/blog-meter-accuracy#how-to-confirm-whether-the-energy-meter-is-damaged-during-shipment

"- Moved CT "A" wiring to "B" and "B" to "A" sorry, I do not understand this operation, please let me know more details about your specific operation.

In fact, we need to confirm why the voltage reading is zero in phase A and phase B.

Please also give us a photo to prove the Ua and Uc are powered by the same wire that is connected to Ub.


As soon as I posted it I realized the ignorance, it was clear in the drawing that all 3 (Ua/Ub/Uc) needed to be connected. For some reason I thought just the 2 were jumpered,  and all 3 would magically be connected on the inside. Dumb mistake on my part. 

Rewired with all Ua/b/c to the same breaker and working perfectly now!   🤣


Thanks for the quick answer!

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