Circuit Breakers for motors

[Kris Verdeyen]

<R92> Speed Controllers may be protected by 20A, 30A, or 40A Circuit Breakers. Speed Controllers may power motors or devices of any size.

That's all the rules say about what fuse is needed on what motor. They do call the wire gauge out for specific breakers elsewhere, but IIRC, in the past they have required 40A breakers for CIMs, 20A breakers for Globes, etc. Is this a change this year, or did I miss something?

[Greg Needel]

They used to recommend using 40A for the cims and drills(when we used to have them) but it was never a requirement, there is no reason that they would prevent you from using more protection through a smaller fuse. The 20 A restriction on the globe was for 2 reasons, if you just used the globe through a spike instead of a victor and the wire size spec.

[Joe Ross]

That's all the rules say about what fuse is needed on what motor. They do call the wire gauge out for specific breakers elsewhere, but IIRC, in the past they have required 40A breakers for CIMs, 20A breakers for Globes, etc. Is this a change this year, or did I miss something?

The rules were the same last year. Before that, it was how you remembered. I asked basically the same question last year.

[dez250]

Don't forget that FIRST has also produced an Electronics Power Distribution Diagram (http://www2.usfirst.org/2006comp/Drawings/2006_ROBOT_POWER_DISTRIBUTION.pdf), and thus has the recommended wire gages and breaker sizes listed for specific items.