Re: [PSUBS-MAILIST] motor seals

[ststev@uniserve.com]

One thing it seems no one is mentioning is the 
limitation on maximum acceleration imposed by the 
magnetic coupling.  No problem with a mechanical 
linkage, but with the field effect device, your 
starting RPM will be limited by inertia of the system 
downstream of the linkage (the prop) plus water 
resistance.  If you accelerated the driving motor too 
quickly, it would be possible to approach a pole 
reversal (> 1/4 turn, for a two pole motor) before the 
prop had time to catch up.  How significant an effect 
is this, and apart from trial and error, is there a way 
to exert some control over this, without PWM?

-Sean

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