Tap Rules

[Chamuit]

I am not very strong on tap rules. So, any help or better options would welcome.

I have a customer with an wood working machine that needs a dust collector.
The existing machine is being fed from a switchboard. Fusible switch. #1 from switch to j-box above floor (28' aff) then #10 to 2nd j-box then to #10 SO cord dropped to wood working machine. This stuff is all 3P 208/120. Machine is 21A collector is 14A.

My question is: can I tap off of the existing circuit with another SO cord and feed the collector?

 

[Smart $]

I am not very strong on tap rules. So, any help or better options would welcome.

I have a customer with an wood working machine that needs a dust collector.
The existing machine is being fed from a switchboard. Fusible switch. #1 from switch to j-box above floor (28' aff) then #10 to 2nd j-box then to #10 SO cord dropped to wood working machine. This stuff is all 3P 208/120. Machine is 21A collector is 14A.

My question is: can I tap off of the existing circuit with another SO cord and feed the collector?

You can tap off the #1, not the #10. And even that depends: 1) Is there OCPD at the switchboard for the #1, and if so, what is its rating? 2) Is there OCPD at the wood working machine to protect the #10 (and the machine :roll? 3) You will have to provide OCPD for the collector tap. There has to be OCPD for the #10. Splicing in SO cord at the j-box without OCPD there is stretching the tap rules, IMO, and that's only if there is OCPD at the machine. If there is none at the macjine it's an outright violation.

 

[RB1]

The No. 10 SO cord is already in violation of the Code. Where taps leave the enclosure or vault where the tap is made, they are required to be installed in a raceway. 240.21(B).

 

[Chamuit]

You can tap off the #1, not the #10. And even that depends: 1) Is there OCPD at the switchboard for the #1, and if so, what is its rating? 2) Is there OCPD at the wood working machine to protect the #10 (and the machine :roll? 3) You will have to provide OCPD for the collector tap. There has to be OCPD for the #10. Splicing in SO cord at the j-box without OCPD there is stretching the tap rules, IMO, and that's only if there is OCPD at the machine. If there is none at the macjine it's an outright violation.

1. Yes there are 30A fuses inside the switch.
2. No, the OCPD is the fusing at the switchboard.
3. Not feasible in this application.

The drops are used because of 400.7.A.6 (NEC 2005)

I want to use an abandoned 3P circuit. Refuse it to 20A. Run pipe over to a stanchion and down into a 4?, set a twist lock receptacle and call it good.