Hi everyone,
I was wondering if someone could help me with sizing transformer secondary conductors? Im a little confuse of how to size the conductor.
Example: I have a transformer that has a secondary nameplate rating of 75 kva 120/240v single phase. I use formula KVA=E x I / 1000. Come up with 312.5 FLA's. Breaker size is 312.5 x 1.25 = 390.625 amps Breaker would be size at 400amp breaker next higher size.
What Im confuse on is do I size wire to FLA or do I size wire with breaker size. The transformer can only produce 312.5 FLA's, Do I have to match the breaker size? I was told to from one person to size with FLA because the transformer can not produce over FLA's and was also told by another to go by the breaker size. Can I get some feed back on this for taking my test.
Thanks
I was wondering if someone could help me with sizing transformer secondary conductors? Im a little confuse of how to size the conductor.
Example: I have a transformer that has a secondary nameplate rating of 75 kva 120/240v single phase. I use formula KVA=E x I / 1000. Come up with 312.5 FLA's. Breaker size is 312.5 x 1.25 = 390.625 amps Breaker would be size at 400amp breaker next higher size.
What Im confuse on is do I size wire to FLA or do I size wire with breaker size. The transformer can only produce 312.5 FLA's, Do I have to match the breaker size? I was told to from one person to size with FLA because the transformer can not produce over FLA's and was also told by another to go by the breaker size. Can I get some feed back on this for taking my test.
Thanks