Industrial Machinery

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memyselfandI

memyselfandI

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Hampton Roads, Virginia
Here is a question. I have a piece of equipment that has a manufacturer installed disconnect switch mounted on a control cabinet. The control cabinet feeds various motors and belts for manufacturing parts. The feeder for this control cabinet is terminated to a terminal block located inside the cabinet, and from there it goes to the disconnect switch. When the switch is opened, it kills power to the cabinet, but the feeders are still energized at the terminal block. The feed comes from a panel approximately 70 feet away. An individual says that it is illegal to terminate these to a terminal block and then go to the switch. I looked at 430.102 and it say that I am to provide a means of disconnect to the equipment, with in sight, and it shall disconnect the control cabinet. I also refenced Art. 670 but found that to be informative only to certain criteria. The facility has a lock out /tag out procedure which it provides at each machine throughout the plant to lock out the feeder if it is necessary. My question is do I need to provide a disconnect for the feeder at the machine before it goes into the cabinet or am I in compliance with 430.102 as well as manufacturer specs?
 
Read chapter 5 of NFPA 79 titled Incoming Supply Circuit Conductor Terminations and Devices for Disconnecting and Removing Power

5.3.1.3 The supply circuit disconnecting means other than attachment plugs and receptacles shall be mounted withing the control enclosure or immediately adjacent thereto. There is an exception if you are supplying 2 hp or less. In that case disconnect can be up to 20' away from the enclosure providing it is within sight and readily accessible.

5.3.1.6 There shall be no exposed live parts with the disconnecting means in the open (off) position.
 
dlhoule said:
Read chapter 5 of NFPA 79 titled Incoming Supply Circuit Conductor Terminations and Devices for Disconnecting and Removing Power

5.3.1.6 There shall be no exposed live parts with the disconnecting means in the open (off) position.
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yea. What he said.

keep in mind, the NEC more or less stops at the control panel and NFPA79 takes over.

I would be inclined to move the incoming power directly to the line side of the disconnect switch.

I wonder why it was made this way in the first place.

Is it possible that the terminals are actually there to feed something that is not supposed to be disconnected by the disconnect switch (such as a lighting transformer)? If so, the wiring would normally be done in yellow.
 
Bob
Is it possible that the terminals are actually there to feed something that is not supposed to be disconnected by the disconnect switch (such as a )? If so, the wiring would normally be done in yellow.
Click to expand...

Yes and if that is the case the terminals should not be exposed. They should be covered to prevent contact with them.

I prefer to have lighting transformer come off of line side of disconnect, but there are cases where other items are supplied from these terminals. :)
 
The control cabinet has a means of disconnect provided by the manufacturer that is attached to the unit which when it is opened kills power to the cabinet, for service. This is a piece of equipment that is designed and assembled in Europe and shipped here where it is installed. Is it required by the NEC to provide another means of disconnect for the feeder at the cabinet when one is all ready provided? Also, lock out procedures are enabled to ensure that all are precautions are taken to ensure that the safety is a priority. I don't have access to a NFPA manual, but I am curious as to why it is not referenced in the articles I mention, when the first words at the beginning of the code book is "NFPA 70". :?
 
dlhoule said:
Bob
Is it possible that the terminals are actually there to feed something that is not supposed to be disconnected by the disconnect switch (such as a )? If so, the wiring would normally be done in yellow.
Click to expand...

Yes and if that is the case the terminals should not be exposed. They should be covered to prevent contact with them.

I prefer to have lighting transformer come off of line side of disconnect, but there are cases where other items are supplied from these terminals. :)
Click to expand...

IEC style terminals are not exposed - being finger safe. IEC terminals are the most common these days, being cheaper generally and easier to use, and take less space.

We normally run the stuff that is not disconnected by the disconnect switch ddirectly off the line side of the disconnect switch but some custoemrs want it to pass through terminals. others prohibit doing that.
 
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