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Re: OLTC Measuring Peak Current

Original poster: "colin heath" <colin.heath4@xxxxxxxxxxxx>

hi robert,
            now thats a nice idea! what size stock was the stainless for
this as i work with tons of the stuff. also what lengths were needed for the
correct reading? i realise this will change with different grades but just
gives me a rough idea as to wether i can fit this into my project.
colin heath
----- Original Message -----
From: Tesla list <tesla@xxxxxxxxxx>
To: <tesla@xxxxxxxxxx>
Sent: Sunday, January 09, 2005 4:18 PM
Subject: Re: OLTC Measuring Peak Current

> Original poster: robert heidlebaugh <rheidlebaugh@xxxxxxxxxxxxxx> > > Adam: The simple way to measure peak current is with a shunt. A shunt is not > subject to frequency degridation like transformers. Low current shunts are > relativly inexpencive, but high current shunts are hard to find and you > usualy must make one. Calibration is not dificult. Start with a low > resistance such as a stainless steel bar. A 1" x 12" piece of sheet metal > works for 100 Amps or less or over 100 amps for short durations. Put a known > current through the shunt of lets say 10 amps then move your amp meter along > the shunt to read 1 amp. Mark this point and rivet and solder a connector to > this point. You now have a 10:1 shunt. Sears sells a small role of pure tin > solder and acid flux in a small blister pack that solders stainless or use > silver solder. To monitor fast time currents connect a scope to your > connection point. NOTE I did not measure the resistance of the shunt. That > requires a calibrated good quality bridge. Few people have one and it is not > nessisary. I have a 1000A shunt made of a piece of stainless round stock. > calibrated to 6 places in a standards lab. You can make it with what you > have in your shop calibrated to the acuracy of your test equipment. > Robert H > -- > > > > From: "Tesla list" <tesla@xxxxxxxxxx> > > Date: Mon, 03 Jan 2005 17:11:04 -0700 > > To: tesla@xxxxxxxxxx > > Subject: OLTC Measuring Peak Current > > Resent-From: tesla@xxxxxxxxxx > > Resent-Date: Mon, 3 Jan 2005 17:20:33 -0700 (MST) > > > > Original poster: "Adam Horden" <adamhorden@xxxxxxxxxxxx> > > > > Hi All > > > > I am currently rebuilding my OLTC. I have rebuilt the controller and > > preliminary test show that it's working in constant BPS mode but the > > interrupted drive needs some work. > > > > I was wondering how I can go about measuring the peak current. I was > > planning to measure it on one side of the capacitor bank (not the > > neutral side) > > > > I don't have room in the low inductance layout for my ion physics > > current transformer (its about 6 inch dia). > > > > I was wondering how I can measure the peak current. > > > > Maybe a current transformer wound on a 1inch ferrite core? > > > > Adam > > > > > >