On Tue, 15 Apr 2014 00:38:06 +0000 (UTC),
(Larry W) wrote:

In article ,
Mike Marlow wrote:
...snipped...
Not to mention that the themal overload in the switch has no idea at all
what the motor is seeing.


Not necessarily true either. I didn't look in detail at theat switch's
specifications, but I believe it had current-sensing heaters in it
matched to the motor size, similar to what a magnetic starter with overload
protection uses.
Which will PREDICT temperature based on load, but cannot take into
consideration reduced air flow and other factors.