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Re: HV meter



Original poster: "Barton B. Anderson" <bartb@xxxxxxxxxxxxxxxx>

Hi Gary,

Often, the ebay 40kV probes are designed for DC measurement. I grabbed some "bad" ones cheap (usually an open resistor). Seems the resistors come in pairs and usually one of the two is good. I simply built a HV divider using the good resistors.

I haven't written anything up on my divider, but basically it's a series of 3 resistors (there's a 3rd resistor between the two HV resistors). This 3rd resistor is a potentiometer used for calibration of which the voltage drop is measured across. I calibrate it by measuring a MOT output (ramped up to the highest voltage my multimeter can withstand in order to increase the accuracy of the divider). I simply use a multimeter across the middle resistor for the reading once it's calibrated.

My point is that even those dead DCKV meters are good for parts.

Take care,
Bart

Tesla list wrote:

Original poster: "Lau, Gary" <Gary.Lau@xxxxxx>

The 40kV HV probes often seen on eBay are usually rated only for DC
measurements.  I've not tried them on AC, and would be concerned that
their very high resistance is not compensated for AC use, and may
deliver misleading results.  Has anyone else tried these probes on 60Hz
AC?

If you only need to measure a HV transformer, it's best to simply
measure your mains voltage, apply 120VAC to the secondary, measure the
resulting primary voltage, and calculate the stepup/down ratio.

Gary Lau
MA, USA

> Original poster: "Gates" <ryker@xxxxxxx>
>
> The meter will be to measure AC voltage from MOT"S ----- Original
> Message ----- From: "Tesla list" <tesla@xxxxxxxxxx>
>
> >Original poster: "Lau, Gary" <Gary.Lau@xxxxxx>
> >
> >You need to first understand exactly what it it you're trying to
> >measure.  DC or AC?  60 Hz or high frequency?  100KHz or 100MHz?
> >Continuous sinusoid or disruptive waveform?  Each of these variants
> >requires a very different approach.
> >
> >Gary Lau
> >MA, USA
> >
> > > Original poster: "Gates" <ryker@xxxxxxx>
> > >
> > > Anyone out there have the plans and parts list to make a high
voltage
> >meter?
> > > Please contact me off list.
> > > Thanks
> > > Gates
> > >
> >
> >
> >
>
>
>