what size wire do I need for 150 amp breaker?

Question

I am hooking up an on demand electric water heater that pulls 125 amps from a 150 amp sub panel. I need to know what size wire to run to the sub panel from the main panel.

Answer 1

If you're asking this here, you probably don't have all the necessary knowledge to do this job correctly.

Please reconsider and use a licensed electrician for this job, if you value your life and house.

Answer 2

The red flags popped up all over this one!!! If any electrical appliance (or any combination of electrical appliances) on that main panel starts pulling more than 25 amps while that water heater is on it will trip the main breakers on your main panel! You're asking an awful lot from that main panel.

With that said; If you can get a look at the electrical service coming from the commercial source to your main panel, determine the wire size and connect your sub panel with the same wire size.

(p.s. Good luck!)

Answer 3

potential equipment pull the main amperage on the preliminary startup. this means a fifteen amp chop observed or compressor ought to draw 20-22 amps on the initiate up. a hundred and fifty' is purely too long of a distance for 12/2 twine. you like minimum of #8 Copper twine. it is for proper circumstances the place the equipment are all in stable shape with stable brushes/switches/ and suitable grounded cords the place required. we've repaired a super style of equipment that have been wiped out because of the fact they have been run off too long an extension twine. a super style of air compressors must be plugged into no longer something different than the opening with twine rated for 30 amp load - nevertheless human beings will run them off of a decrease priced 14/3 extension twine after which ask your self why they burn the automobiles up - even 12/2 cords are no longer sufficient each so often.