On 03/10/2012 05:56 AM, Michael wrote:

Most multi-meters only measure voltages up to 1000 volts. How do you
measure voltages often used with tubes like 3-500z or 3cx1500a7
tubes? Will the range extended from Fluke listed below work with a
1000v 10 mega ohm multimeter?

80K-6 High Voltage Probe
http://www.fluke.com/fluke/usen/acce....htm?PID=55358

The multimeter I have is the Radio Shack 22-801 which is rated for up
to 1000 volts.

Radio Shack 22-801 owner's manual
http://www.radioshack.com/graphics/u...0801_PM_EN.pdf

Thanks

Michael
I actually built a HV meter for an amplifier project years ago using a
surplus 0-1ma panel meter and a string of 10 meg ohm resistors. The
resistors were 1/2 W 5% and the entire string was covered with two
layers of heat shrink tubing for insulation (heated to shrink it around
the resistor string). I hand selected the resistors measuring their
value with my Fluke mutimeter so I actually had an accuracy better than
5% in the multiplier chain. The panel meter I used was intended to be
inserted into a HV circuit so the case was insulated to withstand the
voltage with the meter panel mounted. While I connected the meter
across the full plate supply voltage, if you are using series connected
capacitors in your plate supply (with divider resistors across each cap)
you can connect your voltmeter 'tapped down' on the divider chain and
multiply the reading by the divider ratio. This will be safer than
measuring the full voltage directly, but you will lose some accuracy
depending on the tolerance of the divider/bleeder resistors across the
capacitors. In most cases you don't need to know the plate voltage to
better than 5% anyway.