rxinquestion OP t1_j5pmble wrote on January 24, 2023 at 6:10 PM

Reply to comment by icanthinkofanewname in Making room for Tesla charger 60amp breaker by rxinquestion

At max load, the house is pulling 41A, peak summer based on provider data. Installing the Tesla wall charger that will continuously draw 48a on a 60amp breaker.

Mastasmoker t1_j5qju34 wrote on January 24, 2023 at 9:35 PM

41 amps between two AC units and the rest of your house? Highly doubt thats correct. Its also the inrush current that you have to consider. Your AC units can draw 5 to 7 times their rated amperage on startup. Add that with your charger and everything else in the house and you can trip your main.

rhineo007 t1_j5t93h3 wrote on January 25, 2023 at 12:16 PM

This is completely incorrect. Breakers are rated/sized to allow for this. And it’s not 6/7 times, you rate the breaker 250% of rated load, for most motors.

Mastasmoker t1_j5ta35w wrote on January 25, 2023 at 12:26 PM

Correct they are sized (amp rating) to allow for inrush current on the entire panel but this person is adding a 60 amp circuit for a charger thats going to be drawing 50 amps. Add in all appliances and other devices in the house plus 2 ac units.

Breakers can handle inrush current of startup for a split second period of time. The two ac units, if starting up at the exact time could cause it to trip. It does happen, albeit not all the time. The 5-7 times the rated amperage is based off the nameplate data of the ac unit, not the breaker. Dont know how you thought i meant that.

I dont know what your point was other than to try to say I dont know what Im talking about. Sounds like you know enough to be dangerous.

rhineo007 t1_j5tnsv5 wrote on January 25, 2023 at 2:21 PM

As a master electrician and an EET, your right, I do know enough to be dangerous, but I also understand residential load calculations, and that not everything turns on at once. If those are the ideas you are trying to scare people with, then every house in the world would trip under full load of all the breakers, but that’s not how it works/calculated, but you would know that if you were an electrician. Just saying 🤷