York YS Power fault

[SPD]

Hello: York YS chiller keeps giving me a POWER FAULT on display. Chiller starts runs for 2-3 minutes then i get this power fault code? Chiller has a ssms model 5557l-46a. I have checked wiring between boards and found no problem that i could see. HELP!!!!!!!

[jayguy]

this problem is usually related to the current transformers. watch your amp draw on the panel to see what it is doing during the start up and up to the 2-3 minutes before the fault occurs.

[SPD]

t1 548 t2-551 t3-551 amps at start before shut down t1-134 t2-114 t3-134 amps

[KnewYork]

From the operation manual:

“LCSSS - POWER FAULT”The Liquid Cooled Solid State Starter Logic/Trigger
Board has detected that the compressor motor current in
one or more phases has decreased to <10% of the FLA
for a minimum of 1 line cycle. This check is inhibited
during the first 4 seconds of SYSTEM RUN and until
the motor current is >25% of the FLA. The chiller will
automatically restart upon completion of SYSTEM
COASTDOWN.

Like, jayguy said, check CTs and associated wiring from CTs to trigger board and BTW tou have a SSS7L-46A (not 555)

[SPD]

How do i check The CTs ?

[jayguy]

How do i check The CTs ?

got an ohm meter? look for loose connections. like KY posted, 1 line cycle is very quick and the panel will not update fast enough for you to see it. if everything seems ok, you may need to call in a heavy hitter.