Can you hook the large kitbot fans to a 30 amp breaker??
You can if you want to, but I don’t see the point. Typically they are hooked up to a 20A breaker, which is way too much current to let go through the fan is something bad happens. Really, I think the fans are rated at like 1.5A max or even less. I would typically go a little above like maybe 1/2A or 1A above the fan’s rating because of spike currents needed to start the fan.
The fan voltage is 12VDC.
The fan current is around 1.5A or 1500mA.
A 30A breaker will work fine as long as nothing goes wrong. Remember a breaker is designed to “break” the flow of electricity if the current goes above 30A. Seeing that the fan in no way is supposed to draw 30A of power, the purpose of the breaker would be defeated.
You can for off seaso, but the judges made us put everything but motors on 20 amp for competition. I wouldn’t worry about it too much though if it’s just for off season. We’ve never had a problem with giving a fan too much power. I still wouldn’t use a 40 though, just to be safe.
First, the fan voltage is unrelated to the breaker current rating. Whatever breaker you use, you’d better be supplying the 12 volts needed by the fan. A properly-working fan won’t pull more current than it needs, so the size of the breaker isn’t really relevant unless the fan itself breaks.
Remember, a circuit breaker’s job is to protect the wiring. Regardless of how much current the component is expected to draw, the maximum rating of the breaker should be based on the size of the wires. (The FRC manual gives the rule in the other direction: the gauge of the wires must reflect the size of the breaker.)
If you use a 30 amp circuit breaker, you should be using 14AWG or larger wire.
I will throw in two cents here, the proper method is to use the 20 amp breakers to feed the fan. As Alan pointed out this does nothing to save the fan but does protect the wiring in case of a short. As I remember the fan is a DC brushless design and should be internally protected for over current.
And if you are still concerned, you can buy car fuses right down to 3A and use one of them instead of the breaker. It won’t self-reset or anything, and won’t pass an FRC tech inspection, but electrically there is nothing wrong with it.