Re: Re: Neon power draw, was Yet another newcomer, and from Sweden this time
From: Mad Coiler[SMTP:tesla_coiler-at-hotmail-dot-com]
Sent: Thursday, August 28, 1997 10:45 AM
Subject: Re: Re: Neon power draw, was Yet another newcomer, and from Sweden this time
>Sent: Thursday, August 28, 1997 4:01 AM
>Subject: Re: Re: Neon power draw, was Yet another newcomer, and
from Sweden this time
>> For 12 kv 30 ma, when arcing, I measured 3 to 4 amps input; in other
>> words, my neons are quite efficient. This is presumably thanks to
>> containing capacitors inside for power factor correction, otherwise
>> they'd have to draw more current for the same output.
>> You might consider heavy-duty high-wattage resistors, i.e. light
>> as a cheap substitute for variacs. The limitation of bulbs is that
>> initial (cold) resistance is low.
>Another consideration when selecting a variac for a neon sign
>transformer, is the size of your capacitor. If it's value is such
>that it resonates with the leakage reactance of the neon trannie,
>then the trannnie will draw more than its rated power even when
>PFC caps are used. For example, my 12kV, 30ma trannie, with
>PFC caps, draws 680 watts. The coil gives 42" sparks. Using
>a correctly sized cap is the key to obtaining long sparks from a
>NST driven TC. I used .007uF in this case.
John, you have brought up an issue I had asked the list about and never
got a response. You say "If it's value is such that it resonates with
the leakage reactance of the neon trannie..." How is this determined. In
the designing phase how could one determine if this would happen? And
does this stress the neon two much, or is it ok as long as the gap fires
to discharge it?
Still resonating in Ohio,
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