From: Mark S Graalman [SMTP:wb8jkr-at-juno-dot-com]
Sent: Wednesday, February 11, 1998 4:22 AM
Subject: Re: rotary problem
Dwight take the safety gaps and put them at
the transformer outputs instead of after
the chokes, I believe the filter circuit may be
ringing and causing your problem. Also make
sure you chokes aren't coupling to your primary
On Wed, 11 Feb 1998 01:19:25 -0600 Tesla List <tesla-at-pupman-dot-com> writes:
>From: dwight duncan [SMTP:duncand-at-ccsalpha2.nrl.navy.mil]
>Sent: Tuesday, February 10, 1998 6:46 AM
>Subject: rotary problem
> Mr John Freau made the suggestion of making my stationary
>flat wrt. the rotor disk. I gave this a try and there was a slight
>improvement. I also took out every other electrode on my disc to a
>total of 8. The motor is running markedly faster and is rated at 2400
>and is of the brushed variety. Still my safety gaps are still firing
> My is two 5 Kv 300 ma transformers put in series with the center
>commons on the HV side grounded. This gives me 10 Kv at 300 ma. Just
>after the transformers are 4 nf caps in parallel to ground on each
>the output. next is a laminated iron core common mode choke with each
>at 4 mH. Finally is the safety gap with a ground post in the center
>was set so it would not fire when the feeds were disconnected from the
> John mentioned the problem may be in the toroid. Using the
>from Richard Hull I went for as large of a toroid that I could make.
>a 16" dia. disc with a 4" aluminium dryer hose wrapped around the OD.
>did an order of magnitude calculation and came up with 25 pf. This
>calculation made some assumptions that may not be valid.
> Anyway this is my whole system and I am running out of ideas for
>cause of this problem and to John or anyone that might have some
>please reply and any or all comments are greatly appreciated.
>PS. The secondaries resonance is measured at 220 KHz and the primary
>tapped out at almost five turns.
You don't need to buy Internet access to use free Internet e-mail.
Get completely free e-mail from Juno at http://www.juno-dot-com
Or call Juno at (800) 654-JUNO [654-5866]