York Optiview I/O Board Problem
I got a call from my friend in China that he has trouble on identifying the problem on the Optiview I/O board,
a YK E chiller(No.4) tripprd for "Oil-Variable Speed Pump-Drive Contacts Open",
the operator replaced the VSOP board by removing from another chiller(No.5) that has no problem on VSOP, then he installed the defective board on No.5 chiller, when he was doing the exchange, he didn't turn off the 115 VAC power supply,then on the next day, he found the 5 A fuse burned down, he replaced the fuse, re-applied the 115 VAC and found C1(Capacitor?) on I/O board burned down,
Can anybody here help on idenfying this faulty condition?
what is the C1 on I/O board for? under what condition would it burn down?