On Mon, 06 Apr 2009 06:32:43 -0500, Caesar Romano wrote:
On Sun, 05 Apr 2009 22:44:55 -0500, AZ Nomad
wrote Re 48 volts with switch
off!:

On Sun, 05 Apr 2009 16:20:03 -0400, Percival P. Cassidy wrote:
I replaced some existing incandescent bulbs by LED bulbs, then noticed
that they do not switch off completely but still glow dimly.

Checking the voltage at the lamp socket with a high-resistance
electronic multimeter, I get a reading of 48v!! A few volts might be OK
-- induction, stray voltages, etc., but 48V!!!

48V at high impedance means absolutely nothing.


Why is that?

It doesn't indicate any current flow or even potential for current flow.
Voltage alone, measured with a high impedance meter is little different
than static electricity. Leakage from capacatance between insulators
will throw off a high impedance meter.

Put a 1K resistor on it, and the voltage will drop to zero.