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Re: Confessions of an EE

Subject: 
           Re: Confessions of an EE
      Date: 
           Tue, 18 Mar 1997 14:37:49 -0500
      From: 
           chuck seguin <seguinc-at-algonquinc.on.ca>
        To: 
           Tesla List <tesla-at-pupman-dot-com>
References: 
           1


Tesla List wrote:
> 
> Subject:
>             Confessions of an EE
>        Date:
>             Sun, 16 Mar 1997 16:10:55 -0800
>        From:
>             Skip Greiner <sgreiner-at-wwnet-dot-com>
> Organization:
>             Greiner, Ltd.
>          To:
>             tesla list <tesla-at-pupman-dot-com>
> 
> Hi all but especially new coilers
> 
> I should know better but you might gain from my experience. I have been
> working at relatively low power on the order of 700 to 2000 watts. I
> "play" at the 700 watt level and then try to move up. At 700 watts we
> use less than 10A from the mains and at 2kw something on the order of
> 20A assuming 120v mains.
> 
> I put together what appeared to be a pretty impressive 700w TC,
> something like 48"(+) discharges and thought the design was worth while
> to push to 2kw. Lo and behold I could never get over 54" discharges no
> matter what. Being very frustrated I naturally started checking
> everything in sight with virtually no solution. By the way I monitor
> mains current but not mains voltage. With nothing left to check I
> finally got to the mains and guess what? My input voltage to the neon
> driver was only around 100v using a rectifier type meter for
> measurement. This probably means that the voltage getting to the
> capacitor was even less during operation. That's close to 20%
> undervoltage......major problem.
> 
> Starting from my power distribution panel I rewired everything up to the
> neon input. Now the same meter reads 120v at the panel AND at the neon.
> Better yet on the first firing the discharges went well over 60" and I
> am now doing a major retuning of the whole system.
> 
> Moral: Make sure that you are truly delivering full mains voltage to
> your input transformer under load. You may be losing a major part of
> your discharge length in the feed lines, variac, etc.  to your system.
> 
> SkipSkip,

I must agree 100% on this.  I teach students at Algonquin College in
Ottawa, Ontario; it's challenging to 
teach appropriate troubleshooting techniques.  Some times people do not
go for the obvious.  I tell my 
students to start at the begining; look at the power supply to your
circuit and once you are confident that 
all is ok move on to what may appear to be deffective.

Great advise, from a leader.

Chuck