Re: neons & rsg(sync gap operation)
Sent: Tuesday, August 05, 1997 3:34 AM
Subject: Re: neons & rsg(sync gap operation)
In a message dated 97-08-05 00:56:29 EDT, you write:
<< John, Thanks for the info.
> I think I will try and build a synch gap. But I don't understand what
> makes a synchronous gap to be synchronous. How could one be assured that
> it would always fire at the right time? My coil right know is using two
> 12,500v 30mA neons (60mA total) and the primary resonates at about
> Thanks again for the help.
> Tristan Stewart, CET >>
A salient pole or hysterysis synchronous motor locks up to the
incoming AC, thus the electrodes will line up at exactly the same
point on the AC half cycle at every half cycle. Now either the motor
OR the electrode backing board must be rotated a certain amount,
then fixed in position, such that the firing of the gap coincides with
the peak of the AC half cycle...this is a trial and error adjustment.
Or you can make up something fancy to adjust the gap phasing
while the coil is running. Once you set the gap phase, it will ALWAYS
fire at the proper point on the AC half cycle. But if you modify the
coil, by using different capacitors, a different power level, etc, then
you may have to re-adjust the phase slightly for best results under
the new conditions. Sync motors run at EXACTLY 1800 or 3600 rpm,
if you use 1800 rpm, use 4 spinning and two stationary electrodes, if
you use 3600 rpm use 2 spinning and two stationary electrodes, to
obtain 1 gap firing at the peak of each 60Hz half cycle. Sync motors
lock to the incoming ac, and never drift unless they are overloaded, in
which case they will lose their sync-locked condition.