OCP for Multiple Machines

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Cletis

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Were gonna run a #1 Al 4 wire feeder from a 100 amp 480V OCPD up and over 30 ft to a 125 amp Nema 1 disconnect. We are going to set 70 amp fuses in disconnect for now. The owner will be setting 3 machines later the following week that are 480V and around 17amps FLA (i'm waiting on specs still).

I was hoping to add 3 - 3 port lugs out of load and feed all 3 machines then maybe add internal fuses at each machine depending on FLA. Does this sound good to you all ? I just saw something about this on Automation Direct. Article 430 (which i'm reading now) for setting multiple machines on 1 OCPD but I can't seem to locate yet ? The machines don't need to be started at same time but will probably be running all day long. I'll post specs when I receive if anyone is interested in this thread.
 
I see nothing wrong with your plan.

I would put an unfused switch in though. No need for another point of failure.

Does each machine already have OCPD? If so, you can probably skip that as well, if you can meet the tap rule requirements.
 
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If you supply three machines off the disconnect, with three sets of conductors, each set going only to one machine, you will have to meet the tap rule requirements of 240.21(B) or, if qualified, 240.92(B).
 
Smart $ said:
If you supply three machines off the disconnect, with three sets of conductors, each set going only to one machine, you will have to meet the tap rule requirements of 240.21(B) or, if qualified, 240.92(B).
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I must be missing something. The feeder is coming off a 100 amp main 3 pole breaker to disconnect. Can you explain why that is a "Tap" off the load of fused disconnect ?

I just read this http://ecmweb.com/code-basics/understanding-rules-feeder-taps

So, the difference in calling it a tap is if I come off the loads with say #6 Cu to each machine or if I use #10Cu to each machine (which is what they need) then ?
 
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Cletis said:
I must be missing something. The feeder is coming off a 100 amp main 3 pole breaker to disconnect. Can you explain why that is a "Tap" off the load of fused disconnect ?

I just read this http://ecmweb.com/code-basics/understanding-rules-feeder-taps

So, the difference in calling it a tap is if I come off the loads with say #6 Cu to each machine or if I use #10Cu to each machine (which is what they need) then ?
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Exactly. If your conductors to each machine are not protected at their ampacity, they are taps.
 
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