The following info relates to a building main GFP tripping upon starting of centrifugal chillers (w/ hermetic motors?). This is the second site where I have seen this happen. One with new chillers, one with old. Any thoughts on why?
"The most recent troubleshooting yielded the following information. GFP meter indicates about 160 to 180 amps normally. Jim looked at the highest reading on the meter since the previous reset, and it was 490 amps. He zero'd it and old chiller #1 was started. The meter jumped to 500 amps for about a minute, then backed off to 250 or 260. Old chiller #1 was shut down, the meter zero'd again, and old chiller
#2 was started. The meter again jumped to around 500 amps for about a minute, then backed down to 250 or 260. With both of these units off, the reading returns to about 160 to 180 amps."
"The most recent troubleshooting yielded the following information. GFP meter indicates about 160 to 180 amps normally. Jim looked at the highest reading on the meter since the previous reset, and it was 490 amps. He zero'd it and old chiller #1 was started. The meter jumped to 500 amps for about a minute, then backed off to 250 or 260. Old chiller #1 was shut down, the meter zero'd again, and old chiller
#2 was started. The meter again jumped to around 500 amps for about a minute, then backed down to 250 or 260. With both of these units off, the reading returns to about 160 to 180 amps."