RE: Contactor Question - Order In Circuit

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Cameron B. Prince" <cplists@xxxxxxxxxx>

Hey guys,

Do you suggest the contactor to be before the variac on the line side or
after it on the output side? One of the primary reasons David is using one
is to get the surge required to break the multiple spark gaps. From what I
understand, some of the time when he's just running up the variac, it's not
firing them. So if he started at 0V to protect the contacts, it would defeat
the purpose of the contactor anyway.

I am in the process of adding a contactor to my controller and was planning
to put it on the output side. This way I could use the voltmeter to set the
variac where it should be, get the ARSG up to speed then fire the contactor
sending the power out to the pig. I plan to have a key switch and a dead
man's switch in series with the contactor coil.

Are there advantages and disadvantages either way? What do you suggest?

Thanks,
Cameron

> -----Original Message-----
> From: Tesla list [mailto:tesla@xxxxxxxxxx]
> Sent: Saturday, August 20, 2005 12:47 AM
> To: tesla@xxxxxxxxxx
> Subject: Re: Contactor question, Arc Suppression
>
> Original poster: "Gerry  Reynolds" <gerryreynolds@xxxxxxxxxxxxx>
>
> Hi Bart,
>
> I always try to energize my variac with it set to zero volts.
>  Getting the variac powered up is usuallly my problem.  Once
> that happens, I almost never have problems powering up the
> coil (even with GFI circuit breakers and no EMI filter).
>
> Gerry R.
>
>
> >Original poster: "Barton B. Anderson" <bartb@xxxxxxxxxxxxxxxx>
> >
> >Hi Gerry,
> >
> >I would also bet your coil takes little V adjust to get the coil
> >sparking. I've had this same issue. My coil would benefit
> from a double
> >stack (or even a super-sized variac like Ed Sonderman has -
> something
> >like 50A?).
> >
> >Take care,
> >Bart
> >
> >Tesla list wrote:
> >
> >>Original poster: "Gerry  Reynolds" <gerryreynolds@xxxxxxxxxxxxx>
> >>
> >>Good point Bart.
> >>
> >>It doesnt matter what it use to start the "timer" as long
msnip...