[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

RE: saturable reactor vs choke



Original poster: "Jack King" <ekklekktikk@xxxxxxxxxxx>




From: "Tesla list" <tesla@xxxxxxxxxx>
To: tesla@xxxxxxxxxx
Subject: RE: saturable reactor vs choke
Date: Tue, 18 Apr 2006 17:13:04 -0600

Original poster: "Jim Mora" <jmora@xxxxxxxxxxx>

Hi Gerry, Steve, all,

If you can come up with a silicon based solution that is comparable to the
375 lbs of copper and iron in my truck, I'll be cutting the copper off for
the scrap yard post haste!

...Well I wouldnt wheel it to the curb just yet...I have yet to find a suitable firing card and triacs to approximate what a S-R and old slide chokes do - I mostly roll such systems for NEON people, so our HV transformers arent presented with a big cap and spark gap on the end...but hey, silicon steel and copper fetch good money these days (and then it's of to Mexico or China)

I'll run it up to 15KVA on hot water heater elements and measure the current
draw verses the control voltage. It will be interesting to see how much
linearity it actually has. It would be worth buying one more element I
suppose (4500w/220v) which would run very close to the spec plate. Is there
anything you would like me to test? I will be scoping the wave form.

You may want to parallell a dumb 0-300 V meter on the load, It would be interesting to see how attenuated the volatge is at startup with your load parked on it.

I will
over kill the DC by a few amps and regulate it.

I think your gonna have MASSIVE heat from the elements before you get near 90 volts dc...Just a hunch from past experiments (but mine have been with "240" v units )...


It will be interesting to study what happens on a Jacob's ladder. I'll run
the pig up to 2x 5kva max.

THAT sounds like fun!

We will know more about the inductive/current behavior of this beast by next
week. Be assured that I have no desire to plot the full 90 volts control on
my pig since I want to be on the conservative side of whatever knee there
is. My neighbors would not like a brown out. There are six of us on one pig
which has blown up before.

Yeah, your 5 kva pig wouldnt like you much...and hopefully you werent the culprit on the last pig-popping!


Silicon, Germanium, Fiber, it's all good. Leave me the copper, silver, and
gold!

Jim Mora

ANxious to here of your findings Jim...and I may be able to help you find some suitable smaller saturable reactors...I run into them in things like old induction heaters and forklift chargers all the time!

Jack



-----Original Message-----
From: Tesla list [mailto:tesla@xxxxxxxxxx]
Sent: Tuesday, April 18, 2006 1:23 PM
To: tesla@xxxxxxxxxx
Subject: Re: saturable reactor vs choke

Original poster: "Gerry  Reynolds" <gerryreynolds@xxxxxxxxxxxxx>

I bet all cores have a less than ideal BH knee meaning there is some
softness to it and I suspect that this helps with the "infinite"
current problem.

Gerry R

>Original poster: Steve Conner <steve@xxxxxxxxxxxx>
>
>Hi Gerry,
>
>>What happens if the load is a PIG where the SG is firing???  It
>>seems like the load wont limit the current then
>
>I think you just have to hope that the saturable reactor has enough
>stray inductance left over, even once it's saturated, to ballast the
>pig enough that the spark gap can quench. My gut feeling is that it
>probably would work fine. From reading the archives, it seems people
>successfully use ungapped variacs as ballasts, and these probably
>run in saturation most of the time.
>
>When I really think about it, it seems that a small ballast choke
>sized to run the maximum power you want, combined with a pair of
>back-to-back SCRs wired like a huge lamp dimmer, would function
>identically to a SR, but be a good deal smaller and lighter. But i
>guess we want to keep the silicooties out :-<
>
>Steve
>
>
>