Jamie t wrote in
:

Rob wrote:
On May 29, 1:48 pm, Malissa Baldwin
wrote:

On May 29, 7:21 am, Rob wrote:


I have several DMMs, including a Fluke 77. Let's say I'm testing a
high voltage, possibly charged cap such as a motor run capacitor. Is
it safe to use the DC voltage measurement function to see if the cap
has been safely discharged? What about on cheaper DMMs, is this
typically possible? Does it make sense to measure the resistance
across the leads of a cheap DMM with another DMM when it is in DC
Voltage mode to see if this would be the case?

Have you tried Google?


I certainly did. The answer I was looking for was that DMMs have
effectively infinite impedance when measuring voltage and would not
discharge a capacitor when connected across it.

by standard, they have 10 Meg ohms ..



Not necessarily;the cheapo Harbor Freight DMM I have is only 1 MegR,and
I've seen a 22 MegR DMM.

but even 1 MegR would not discharge a cap very fast.

--
Jim Yanik
jyanik
at
kua.net