Breaker for Large CIM

[Gamer930]

I looked through the rules and not finding an answer to my question.

What size breaker do we have to use for the Large CIM like motor ("Mini Bike Motor")??

I see R82 R83 R84 for use of wire sizes and R92 that "Speed Controllers may be protected by 20A, 30A, or 40A Circuit Breakers."

In the power distrubution guide it just show "CIM Motor".

What am I missing??

[jrocket567]

Do not believe that there are any regulations specifically determining the size of the breaker, but since P=IV, the more current you got the more power you got-- go with the 40A unless you got a reason to scale it down.

[Kevin Sevcik]

R82 through R84 tell you all you need to know. If you want to protect it with a 40A breaker, you must use 12 AWG wire. Or if you really want to wire it with 18 AWG, you must protect it with a 20A breaker. Pick your breaker and determine the wire gauge or pick your wire gauge and determine the breaker.

[Gamer930]

That is what I thought. Just checking that I didn't miss something this year. Wouldn't think that FIRST would let us pick what ones we use just because of safety reasons.

Thanks Again

[Al Skierkiewicz]

Remember the breaker rules protect the wiring, not the motor. When asked, I am recommending the 40 amp breaker and #10 for any Chalupa motor. If you are designing the large motor for some miniscule task, you could save a little weight by going to a smaller breaker and wire.