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RE: Wiring the entire circuit

Original poster: "Lau, Gary" <gary.lau@xxxxxx>

With a sync motor, the position of the shaft is synchronized with the
waveform of the AC power supply, and the waveform of the NST.  This is
so that the gap "contacts" can be set to "close" at the same point of
the waveform, every half-cycle.  The gap will fire at roughly the peak
of the cap charging cycle, 100 times per second with 50Hz power.

With an async motor, there is no relationship between when the gap fires
and the phase of the AC power.  The problem with using async rotary gaps
with NST's is that async gaps frequently use a variable speed motor to
permit experimenting with different BPS speeds.  If the speed is set too
low, the cap will not be discharged frequently enough and the voltage
can climb too high, and damage the NST.  If you can swear to always keep
the BPS (gap closure rate, or Breaks Per Second), I don't think there's
any problem with using an async RSG with an NST.

Regards, Gary Lau

> Original poster: Justin Oliver <justin@xxxxxxxxxxxxxx>
> Hi,
> What is the difference between asynchronous and synchronous motors ?
> is the motor synchronising to ? And how does this affect an NST ? I
> some enlightenment :)
> Cheers,
> -j