motor taps

[strangmeyer]

I have (4) 480v 3phase motors on a 20amp circuit with each motor having a FLA of 3amps. What is the max length off the main run I can tap? Also do need a fusible disconnect at each location or can I just install a motor rated switch?

Paul

 

[tom baker]

Re: motor taps

Are you installing a motor tap? The rules are in section 430 Part II and 430.28, there are two types of taps, ten feet and 25 feet. Please review the section to make sure we are talking about the same thing, and not a voltage drop issue.
The feeder has to be protected per 430.28. A disconnect is required for each controller per 430.102A)and for a each motor per 430.102(B), with in sight. The motor disconnect has to be capable of being locked open by a permanently installed method, the type of disconnect does not matter, however most often a fusible switch is used.

[ October 28, 2003, 10:46 PM: Message edited by: tom baker ]

 

[noxx]

Re: motor taps

Tom certainly your experience here exceeds mine, however I am under the impression that the means of disconnect in this case must be fused. The protection on the branch ciruit serves for ground fault only, the motors themselves must be protected at no greater than 250% (inverse time breaker) or 175% (time-delay fuse).