[Prev][Next][Index][Thread]
Re: Using sync gaps
In a message dated 98-09-28 00:14:25 EDT, you write:
<< Hi John,
> In my case, nothing else but the gap needed to change. My single 60mA
> neon is a non-resonant charged system (the neon's voltage and current are
> 15kV at 60mA with 120 VAC in charging 20nF of capacitance). It was always
> designed to run at 120 BPS My attempts to run with lower value caps and
> higher BPS never worked as good as the 120 BPS non-resonant mode (I
> probably didn't turn it up high enough :-)).
Hi Terry,
Yes, your cap is *big enough* to do the job.
> I did put a powerful safety
>gap on the neon output but this is more to protect against secondary from
> primary strikes which modeling shows is "bad" (I don't use strike rails).
I don't either.
> However, with the protection gap, the neon and all will be kept within
> their ratings in such an event.
> You are very correct in pointing out that if you change from a static to a
> sync (or async) gap in a resonant charged system, you must have an
> effective safety gap system to protect the neon from over voltage and over
> current. If the gap miss-fires, the over voltage will arc at the gap and
> in effect provide a load to drain the energy from the rising voltages of
> the resonating charging system. If this load were not there, the resonance
> could easily charge the system up to several times the normal voltages and
> blow the neon, caps, etc.
Those safety gaps are great. I carboned tracked a couple neons
before I started using them. The async gaps are esp. destructive to
the NST's (they demand, to permit coil operation, a wider safety
gap due to the erratic and skipped firings as you said, but I didn't
really experiment much with the asyncs + NST combo). At least
the sync-gaps fire every half cycle unless somethings really wrong.
John Freau
> Terry Fritz
>>