I have (2) 460v 3ph 7.5hp(11 FLA) Make-up air units within 15' distance. The unit came with control center w/ disc.(I am not sure they have a fused or non-fused disconnect switch. I am checking on that with mfgr.) & starter installed as a listed factory assembly. Per NEC 430.53(D), they were fed with one branch circuit with same ampacity conductors. ( I am not sure each motor overload device & controller are listed for gruoup installation. I am checking on that, too.)
Electrician brought up the question saying that we have to have fused disconnect switch for these units because multi-motors share one branch circuit even though disconnects are factory installed unit. He is referring 430.28 Feeder tap rules.
Is he correct? Do I have to have additional fused disc. swiches for each unit if mfgr furnished disc. switch is non-fused? Units are already on site so we can't have mfgr change their disc. switches?
Thanks for your answer in advance.
[ March 03, 2004, 04:54 PM: Message edited by: jkim780 ]
Electrician brought up the question saying that we have to have fused disconnect switch for these units because multi-motors share one branch circuit even though disconnects are factory installed unit. He is referring 430.28 Feeder tap rules.
Is he correct? Do I have to have additional fused disc. swiches for each unit if mfgr furnished disc. switch is non-fused? Units are already on site so we can't have mfgr change their disc. switches?
Thanks for your answer in advance.
[ March 03, 2004, 04:54 PM: Message edited by: jkim780 ]