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New gap design



As I mentioned the other day, I am designing a new linear gap for my 6" coil 
running at 7 kva.  I am curious to see if this gap will quench and to compare 
it's performance against my async rotary.  I plan to use 11 of the 1.0" dia 
copper tubing coupling pieces for a total of 10 gaps.  I will also use a 
vacuum motor to create strong air flow through the gaps - for quenching and 
cooling.  I plan to design the gap so the copper pipe sections are gapped at 
.030" by using small spacers between them at the ends.  By changing these 
spacers, I will be able to adjust the gap distance.

I am running a 14.4 kv  5kva distribution transformer at about 7 kva.  I am 
not exactly sure what the output voltage is but know I have some primary 
losses due to the inductive and resistive ballast.  I am also using the 
higher output tap on the variac, so for sake of discussion, let's say the 
output is 15 kv.  This would be 21,200 volts peak to peak - so the cap would 
charge to one half of this or 10,600 volts.  How do I determine how wide I 
want the gaps set to fire at about 10,000 volts?  Is the .300" that I have 
planned close?

How about heat dissipation?  How hot is this gap going to get?  I recall 
someone saying that the gap eats up about 7% of the available primary power.  
Is this close?  Does that mean that I will have 7% of 7kva or about 500 watts 
dissipated in the gap?

Thanks,  Ed Sonderman