HZ in motor with switch turned off
HZ in motor with switch turned off
(OP)
I have come across something I would consider weird. Why is it that with the switch turned off and the motor still being plugged into the wall would it have a HZ reading matching the HZ of the wall plug?





RE: HZ in motor with switch turned off
RE: HZ in motor with switch turned off
Could be only one leg is interrupted by the switch?
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(2B)+(2B)' ?
RE: HZ in motor with switch turned off
RE: HZ in motor with switch turned off
RE: HZ in motor with switch turned off
How about some details on this circuit and where you are measuring this frequency.
RE: HZ in motor with switch turned off
Yes I was talking about the Frequency of the electrical current going into the circuit. The circuit is pretty easy, wall plug to a single pole switch to the motor. I was measuring the Hz on the motor when the motor was off. I also made the assumption that the Switch would turn off everything. But if I want the Hz to go away I would need a double pole switch? I put the switch on the black which I made sure was the live wire not the neutral.
Is there any further insight?
RE: HZ in motor with switch turned off
On another note. I don't think you're following the comments which are directed at the proper description for what you are doing. You measure frequency. The unit of frequency is Hz.
To answer your basic question. The reading is likely either from induced voltage or possible your neutral has a small AC voltage on it.
RE: HZ in motor with switch turned off
When you are seeing 60 Hz, switch the meter to volts with the same connection and see if there is any voltage.
Try unplugging the wall plug and see if the frequency indication goes away.
Bill
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"Why not the best?"
Jimmy Carter
RE: HZ in motor with switch turned off
When I unplug from the wall the frequency does go away. So I have set something up wrong. I thought I was being careful and making sure that the black was the hot one and the one that is being interrupted by the switch. Is it possible that the neutral has a current on it because the neutral in the house is shared?
When I switched to Volts there wasn't anything measurable... Measuring frequency is the same as measuring volts where you are hooking up the two poles to the voltmeter and when you measure amps you are hooking it up in-line.
RE: HZ in motor with switch turned off
Best to you,
Goober Dave
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RE: HZ in motor with switch turned off
RE: HZ in motor with switch turned off
I'm thinking it could easily be a small voltage on the neutral as well. The neutral better not have any current at your motor with the motor off. However, a voltage drop on the shared part of the neutral wiring may be causing a small voltage at your motor. It doesn't take much of a signal for some meters to measure a steady frequency. I've seen a meter with the leads not connected but close to some power wiring still showing a steady 60Hz on the display.
RE: HZ in motor with switch turned off