View Full Version : Sub Panel Question
UsaveU
Jan 24, 2012, 06:07 PM
I have a issue on my personal property (not one I'm rehabbing).
I just added over the summer 90lf of heat tape for my plumbing under my house, all together they will pull a max of 15amps (the heat tap is thermostat controlled so they will not always be on). Now when I installed them I didn't think about having the room in my breaker panel but as it turns out I don't have the room to add a breaker. So can I add a sub panel and remove a circuit from my existing panel and move it to my sub panel, that way there is a spot to put a larger breaker to power the sub panel?
If I confused you on that last part let me know, I'll try to re-write it in a better way.
stanfortyman
Jan 24, 2012, 07:22 PM
So can I add a sub panel and remove a circuit from my existing panel and move it to my sub panel, that way there is a spot to put a larger breaker to power the sub panel? Yes, this is a classic sub-panel install technique. :)
You know you'll need either a 240v circuit or two 120v circuits.
UsaveU
Jan 24, 2012, 07:50 PM
Yes I know, I'll be using 2 120v circuits, currently being used by 15 amp breakers. I found a 100amp Square D sub panel that with 10th spaces. From what I have found out through my research I plan to put a 60 amp breaker in to power the sub panel, and move the 2 15 amp circuits to the sub panel as well as add a 20 amp to power my heat tape. Also I have read that I should use 6-3 wire with the 60 amp breaker, and to make sure that the neutral and ground do not connect until they are back in the main breaker panel.
Does all of this sound correct.
tkrussell
Jan 25, 2012, 03:42 AM
And you read the instructions for the heat tape and understand you need to protect the heat tape with 30 milli-amp GFI circuit breaker?
This is not your standard GFI device, which is 5 milli-amp.
UsaveU
Jan 25, 2012, 04:53 PM
All that it says in the instructions is that they highly recommend a GFCI circuit.
If you would please, explain what a 30 milli-amp GFI circuit breaker is and why you think that I would need one.
tkrussell
Jan 26, 2012, 03:50 AM
Why? Because in the 2008 edition of the National Electric Code:
ARTICLE 426 Fixed Outdoor Electric Deicing and Snow-Melting Equipment
426.28 Equipment Protection. Ground-fault protection of equipment shall be provided for fixed outdoor electric deicing and snow-melting equipment, except for equipment that employs mineral-insulated, metal-sheathed cable embedded in a noncombustible medium.
You will find that the standard 5 ma GFI device is for personnel, and 30 ma GFI device is for equipment. If you use the standard 5 ma GFI, it will trip often.
You will need to purchase a 30 ma GFI circuit breaker from an electrical distributor.
stanfortyman
Jan 26, 2012, 04:44 AM
TK, I really don't consider pipe heat tape to apply here. It's not de-icing or snow melting cable. And most pipe heat tape I have seen is metal sheathed.
tkrussell
Jan 26, 2012, 08:22 AM
OK sorry, I did not see " on plumbing".
Stan is correct, heat tape on plumbing does not need GFI protection.
Being in Maine, and dealing with de-icing cable now, I read too quickly.
Carry on. Slap on the wrist for me.
UsaveU
Jan 26, 2012, 04:48 PM
Your forgiving tkrussell, if it were not for you and the other guys/girls on here I would be even more nervious about my rough in inspection on Monday the 30th. All the answers that you guy/girs have put on my posts and other peoples posts is what has got me a good plan for wiring the whole house this weekend (the house I'm rehabing).