zemingduan
Senior Member
- Location
- Philadelphia,PA
- Occupation
- Electrical Designer
I'm now working on sizing a 2.4kV to 480V transformer for a nominal 160 tons chiller. The unit power is 175.61 kW. It has 4 direct-drive hermetic,3600 rpm 60HZ compressor with 69A RLA, two per circuit. It also has its own factory-installed control panel. See the pictures below.
My question is that is 225 KVA 2.4 KV to 480V transformer enough for this chiller. The unit power is 175.61 KW but the MCA is 317A which is 317A x 460V x 1.732 = 252.56 KVA and it has 4 compressors with 69 RLA. My co-worker thinks we should use a 300 KVA transformer. But I think MCA indicates the minimum circuit ampacity. It seems that there is no code requirement for sizing the transformer with MCA. And it's highly possible that the 4 compressors won't work at the same time. What do you guys think? Is there any other consideration here? What is the price of a 225KVA and 300KVA 2.4KV to 480V transformer?
My question is that is 225 KVA 2.4 KV to 480V transformer enough for this chiller. The unit power is 175.61 KW but the MCA is 317A which is 317A x 460V x 1.732 = 252.56 KVA and it has 4 compressors with 69 RLA. My co-worker thinks we should use a 300 KVA transformer. But I think MCA indicates the minimum circuit ampacity. It seems that there is no code requirement for sizing the transformer with MCA. And it's highly possible that the 4 compressors won't work at the same time. What do you guys think? Is there any other consideration here? What is the price of a 225KVA and 300KVA 2.4KV to 480V transformer?