Potential not read by wiggy

[realolman]

The other day i was troubleshooting a 110vac solenoid circuit and read 99 volts on the de-energized circuit with a digital multi meter. I got an ideal solenoid voltage tester (wiggy ) and with that I read nothing.

I figured I was good, but when the wires rubbed together there was still kind of a nasty looking arc there.

I was wondering your thoughts on the potential that still existed in between the levels the DMM read and what the wiggy read.

There is the solenoid tester part of the wiggy and there is also a neon(?) lamp.

If neither "light up", is there definitely not enough power there to be concerned about?

 

[zog]

You may want to read this View attachment Prox voltage detector operation.pdf

 

[realolman]

I guess I was more curious about the minimum ...( I don't even know how to express it )... the "minimum power level" that a wiggy will read.

There is something about the maximum power transfer occurring when the power supply and the load both have the same impedance. That has something to do with the reason the DMM reads the voltage... it has a very high impedance... and the wiggy does not ...because it has a much lower impedance.

 

[Lcdrwalker]

I would guess that what you were reading with the DMM is an induced voltage. That wouldn't have enough potential to energize the solenoid but it would have quite a bite. Unless I am absolutely sure something is deenergized and tested, I treat it as hot. I have this thing against being bit...:weeping:

 

[iaov]

Iwire suggested in an earlier thread putting both the wiggy and the fluke on it and see what happens to your ninety volts when the wiggy is across it. If it goes close to zero, it is induced and it will not spark or hurt!