Re: (ET) Over voltage on DC motors

["David Roden" <etpost drmm net>]

I'm not a motor expert, but I know that many road EV hobbyists run series 
DC 
motors at well over their rated voltage. Using 96v motors at 120v, or 120v 
motors at 144v, isn't uncommon.  Some of the drag racers go far beyond 
that.

However, remember that these motors are designed for multiple decades of 
service in forklifts, burden carriers, and the like, running 8 or 12 hours 
at a stretch.  In 30 years of 8 hour days, that's 62400 hours of use.  By 
contrast, an automobile run 100000 miles at an average of 45mph has only 
2222 hours of running time.  Thus, if by overdriving a forklift type motor 
you reduce its life by a factor of 10, you still have plenty of service 
life 
for automotove use.

Small motors like the ET lift might be something else again.  These are 
window lift motors, designed for intermittent use.  I suspect that plowing 
a 
driveway in witner is already using them above their duty ratings, and the 
standard ET connection runs them at 50% over rated voltage to boot.

Something to think about, perhaps.


David Roden - Akron, Ohio, USA

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