single phase current

[cwilliams100]

working on chiller 30HXA126RZ-600BA circuit b throwing out alarm single phase current checked voltage ok also took contactors apart no abnormal wear checked connections on CT's and at CPM ok checked amp draw while running once alarm is reset circuit may trip in 2 hrs to 5 days looking thru book found no information on trouble shooting CT's or CPM's ohmed out CT's any way showes closed no resistance but so does circuit A which has no problems.

Thanks for any help in advance

[gyhooyabat]

Did you confirm your incoming voltage is stable? That usually causes this issues. Physically check your torroids to make sure they are completely connected, no loose ends? Depending on which torroids (CT's) you have the resistance should either measure between 65 and 70 ohms (part # 30 GX502786) or between 38 and 42 ohms (part # 30GX504711). Finally you might want to dry run your starters to make sure all contacts are closing and none of them are pitted? No resistance across them? Can you give us the serial number so we know what vintage machine you have?

[Dallas Duster]

Are you sure you didn`t have .6 ohms between the CT`s ? What is your voltage imbalance ? And what is your current imbalance ?

[cwilliams100]

serial # 1398F33837 incoming voltage L1 460 L2 462 L3 461 checked 4 different times throught out day. Have rebuilt all contactors in this machine 6 months ago due to pitting amp draw while running L1 53 L2 54 L3 51