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Phase Current Variation

Phase Current Variation

Phase Current Variation

(OP)
I have a power monitor connected to the input of a 440VAC 3-phase voltage regulator. The input transformer is a delta configuration with no neutral.  Is it normal to see a difference in the phase current measurements?  I am observing the following:  L1=0.521A, L2=1.561A, L3=1.964A.
What would be the explanation(cause)for this?
Thank you for helping me understand.

RE: Phase Current Variation


With balanced phase voltages, 3ø current imbalance is usually load based.  What is the regulator powering?  Of less importance, is the ‘input transformer’ separate from the regulator?
  

RE: Phase Current Variation

(OP)
I need to correct my initial thread entry.
The power monitor is connected to the OUTPUT of a 440VAC 3-phase voltage regulator. The OUTPUT transformer of the regulator is a delta configuration with no neutral.  
The regulator OUTPUT is supplying a welding machine's 3 phase tranformer input primary winding whose secondary is providing the necessary voltages for the torch and circuitry of welding machine.  I am observing the different phase curents with the weld machine in an idle state and when it is in a weld state.  Sorry about the confusion.  

RE: Phase Current Variation

Have you check for harmonics?

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