Quote:
Originally Posted by Chris is me
54A is on the very outer edge of the current breaker tolerance band; I would not rely on your mechanism being able to consistently pull exactly 54 amps. If you have a slightly out of spec breaker, or your mechanism has marginally more load than you expect (various ineffiencies, etc), you'll have a bad time, especially since that doesn't even factor in voltage drop. It is reckless to give people the general advice that they should expect and plan for their motors to draw 54 amps under design load.
With that all said, the other motors with max power drawn at more than 40 amps include the mini-CIM, BB-775, BB-550, etc. Basically, any motor you should be climbing with.
The other danger with gearing at exactly mass power is that once you tip over that critical point, you're getting less and less efficient performance out of your motor as your load increases.
You also don't want to run fan-cooled motors at 50% stall generally; it's not great for them to run that hot. Be conservative here; you're not going to win the World Championship with a climb that's 300ms faster than your opponent if your motors smoke.
There's some benefit to climbing quickly, to a point, but this isn't a race, and you just want to complete it reasonably quickly. You can easily get there with 1 CIM / 775pro geared conservatively for less than 40 amps under load - add a second if you really want those sub-2s climbs; don't overwork 1 motor.
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When I'm designing mechanisms I like to use all of the edge case values and incorporate my FoS into the load. For that (especially with climbs not taking longer than 6s) I would use 54A and make sure to include a significant FoS in my load. If you do it differently, that's fine.
I agree with pretty much everything you are saying; my team's climber is powered by 2 BAGs which gives us plenty of power and the ability to add more if needed by switching to a different dual-motor VP input. That being said, while I agree a blanket statement saying you can run all the other motors at max power probably wasn't the best idea, a blanket statement that you shouldn't run any of them at max power isn't really called for either. I'd be interested in seeing data about running fan-cooled motors at half speed. There are a lot of factors here that need to be considered on a case by case basis imo.