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Getting 24VAC transformers in phase sequence

OurTown

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I thought this would be easy but it is not working for me. Three phase 208V transformer input. I'm not sure how many combinations are possible but I think I tried 6 different ones on one bay. My thought is to get two bays to read zero volts between them on the meter and then work on the one that is still out of sequence. For some reason I can't get any of them to read zero volts with any of the 6 combinations of legs and terminals. What am I doing wrong?
 

Eric H

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What are you trying to accomplish?

if I was trying to do this I’d start at the breaker panel and identify which wires are on the same phase. Then, I’d do a continuity test from the identified wires at the panel to the wire at the motor starter. Attach phase 1 at the panel to position 1 on the motor starter, phase 2 to position 2 on the motor starter…
I may be wrong but there are 8 different possible ways to get this wrong and only 1 right way using guesswork. Adding the 2nd, 3rd and 4th bays increases the odds of getting it wrong.
 

OurTown

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I have the incoming power to the transformers in phase with each bay. Now I have several bays that on the 24v side check 3 ish volts to one another, some that are 14 ish volts and some that are 17 ish volts. This is when comparing only the left terminal to the left terminal on each bay and then comparing the right side terminals with each other. Shouldn't they be zero as well like I have on the incoming power to the transformers? Also how I found the different phases I turned off the breakers and tested for continuity of each wire from the output side of the breakers to the motor contractor terminals. They are color coded wires and they all jived. Black to leg one, red to leg two and blue to leg three. The strange thing is that from red to black there was only about 6 ohms. This is also true when comparing all the bays. Each wire tested zero ohms individually. The blue wire was open to all other wires. The motors all work fine and turn in the correct direction. How could the red and black wires be connected? Not a dead short but close. Is it because these are the wires that I'm using for the transformers and that is the resistance on the coils? Someone on Facebook recommended grounding the 24v commons and not running any grounds to timers and such. Currently they are isolated from ground but I do have grounds running to my timers now with my new bay cables. Had to remove them before before because Morris at Dixmor recommended it because we had a strange issue in one bay. Thoughts on this?
 

OurTown

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All I'm asking for at this point is if you have the primary side of all your transformers in phase sequence (read zero voltage from one bay to another) then do your secondaries read zero from bay to bay also? If yours do read zero, are your secondary commons grounded?
 
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