Re: HV voltage divider

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Kevin Ottalini by way of Terry Fritz <twftesla-at-qwest-dot-net>" <ottalini-at-mindspring-dot-com>

Richard:
    My fluke HV probe uses a 1009 megohm resistor in series with a 1Megohm
resistor then to ground.  The DVM goes across the 1Megohm resistor.

This gives me a total of 1000:1 divide ratio with the 10Mohm meter impedance
as a minor offset to the ratio.  Just don't leave off the ground clip!

This works well for AC 60HZ as well as DC, but poorly for higher
frequencies.

The other way would be to use a 100uA or 1ma ammeter (dvm too)
in series with a resistor.  I did something like this for my DCTC.

Look here for schematic, pictures and light commentary:
http://www.mindspring-dot-com/~ottalini/My%20little%2020KV%20Meter.htm

Kevin

----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Friday, March 01, 2002 7:09 AM
Subject: HV voltage divider


> Original poster: "Richard Williams by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <richardwwilliams-at-earthlink-dot-net>
>
> I have a 990meg ohm resistor salvaged from a HV DC probe whose meter was
shot.
> Can I add a resistor in series, 10 meg ohm?, to ground to measure HV?
Haven't
> tried it since I'm leary of inflicting damage to my digital meter since
I've
> never done this before. Input impedence of the meter at the 700vac range
is
> 10meg so would that "look" like a 5 meg resistor overall ?
>
>
>