dollis

6AWG under 100' is good for a MAX of 60Amps! He is VERY right not to use a 100 A breaker. The shop can have a panel with 150 Amps capacity though(7 breakers of 20Amps) just like a house breaker box is 3-4 times the 200Amp if all totaled. I would split the lights on its own breaker. The AC unit has a 50 "probably" for what is called FLA Full load Amps + 30% for start up current rounded up to next larger standard breaker size. If you don't have a use for the 240V circuit the scrap it and use the spaces. Lights + outlets on the same circuit is an accident waiting to happen. Would you want to use a skew in the dark? or have some one turn the lights off when your router is running? Lights go out instantly motors DONT stop instantly. I would RUN from the one that wants to install the 100A breaker. Get another electrician to look at your shop. Inform him that it is for a temporary ONLY if you are sure about the addition.

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