Hi all, this question is from a fellow engineer that I work w/. I have looked in the NEC and all I can find is that it says the lugs need to specified for more that one conductor. I personally looked at the panel in question and personally can't understand why we can't put a #12 or #10 solid on these lugs. Any advice would be appreciated. The following is the question from the EIC.
Thanks for your advice
Question:
Is it possible to obtain power for a new fire alarm panel ahead of the main breaker of an existing panelboard, by line-tapping the panelbaord main breaker lugs and inserting a second conductor in the lugs? The incoming lugs are rated for single conductor #6 thru 250 MCM, and presently have #4/0 wire. A #12 solid tap conductor would be roughly the size of the individual strands of the #4/0, and there would be adequate space in the lug for this added wire.
If this is not allowed per Code, is it possible to provide split-bolt connectors for the tap on the incoming wires to the panel, just before they land on the breaker terminals?
A lockable branch breaker is unfortunately not an option because the fire alarm panel is required to shunt trip the main breaker under an alarm condition with the purpose of shutting off power to process equipment for safety reasons. And unfortunately the existing panel is only a few inches off the floor, and fed from a conduit that stubs up through thru the floor, so cutting in a junction is not feasible
Thanks for your advice
Question:
Is it possible to obtain power for a new fire alarm panel ahead of the main breaker of an existing panelboard, by line-tapping the panelbaord main breaker lugs and inserting a second conductor in the lugs? The incoming lugs are rated for single conductor #6 thru 250 MCM, and presently have #4/0 wire. A #12 solid tap conductor would be roughly the size of the individual strands of the #4/0, and there would be adequate space in the lug for this added wire.
If this is not allowed per Code, is it possible to provide split-bolt connectors for the tap on the incoming wires to the panel, just before they land on the breaker terminals?
A lockable branch breaker is unfortunately not an option because the fire alarm panel is required to shunt trip the main breaker under an alarm condition with the purpose of shutting off power to process equipment for safety reasons. And unfortunately the existing panel is only a few inches off the floor, and fed from a conduit that stubs up through thru the floor, so cutting in a junction is not feasible