mcquay start fault

[billyp7999]

whats a start fault on a mcquay with a micro tech 2, also behind the first panel there is a circuit board with an led with the symbol ut5 on it, any help would be great, if u cant tell i dotn have alot of experience with the lovely mcquay
ags25oa27-er10 stnu020900019

[abctech1]

Starter fault on a Micro tech 2 means you have a starter fault.
The led on the starter board says UTS not ut5. this means the motor did not get, UP TO SPEED before the up to speed timer ran out. may need to set the up to speed timer up 5 sec. or P1 needs to be increase to FLA.

[Slipkot511]

Actually, UTS is not a fault, it is status. "UTS" is the default display once a successful transition was made to the bypass contactor.
If you have a newer D3 card on the chiller, parameter P13 changes the display. Also, parameter P50 will display the fault history.
The easiest way to identify a D3 is if you have a "reset" button next to the LED display. If not, then you have the older legacy board & there is no fault log.

[keithg01]

...I'm getting an F45 fault. the book shows it as a "bypass contactor fault on stop". Only one compressor on each of the two chillers trips this alarm yet, the starter parameters are set up identical, and the operating pressures, temps, oil levels and oil pressures on the two chillers are very close to each other. These chillers have low hours, are in excellent condition, and have had the voltages and phases checked regularly by the onsite electrician. Sometimes they run for a month without tripping, sometimes a week. This is becoming very annoying, and Mcquay tried to help, but I don't think they understood thecause of the fault...any suggestions ?