Guys when measuring AC voltage ....


Senior Member
Guys when measuring AC voltage on a multimeter do I use the setting V --- or the V~
The V~

Hey Rupp, if you need help with this give me a PM with your phone number and I'll call you if you would like!

What exactly are you measuring?

BTW, the other V- is for measuring DC voltage.
I'm trying to measure the output of my magnet wrapped around my TV power cord. Does it matter which wire I run through the magnet? Thanks for the offer and I may take you up on it.
Should not matter, just as long as it is only one cord (wire). Do you have a link on the magnet (I want to make sure of its output type)?

What will you be using to monitor the magnet (Ocelot/Secu16, Power Flash Module, etc...)?

It seems to me after looking at the data sheet that you have to provide a "burden" resistor across the terminals of the leads (across the two power flash input terminals).

Do you have something like a 1K or 5K resistor around? How much does your TV draw in current (is it shown on the back of the TV or the instructions)?

I forget the settings the powerflash should be in as I don't use them now (since I got the SECU16-I), but I'm thinking something like A, Mode 3 (not sure).

I'll try to go on X-10's site later on tonight and see if I can look up the Power Flash instructions.
I just attached the magnet and checked and it's reading 10.4 V. Why would I need a resistor?
Well, if that is what is being read, then you are probably OK, I really couldn't tell from the documentation if the burden resistor was included in the unit or not.

Is this now working OK with the Powerflash unit?
Rupp said:
Why would I need a resistor?
Rupp, If you are reading 10.4 volts, you probably don't need the resistor.

The resistor sets the sensitivity of the CR3110, and you have maximum sensitivity without the resistor. You would need the resistor:
1) if the voltage you measured was too high for the PowerFlash, or
2) if the small amount of power that the TV draws when it is off is enough to turn the PowerFlash on.

The resistor is always required if you are using the CR3110's output to make a measurement of the current draw, since the resistor sets the ratio of current draw to output voltage.
Yes BSR it's working perfectly. I thought I had an additional powerflash interface but it was a universal module so I had to temporarily move one but after doing this late last night it works beautifully.