I have a high velocity fan that seems well-made but quit on me last year. When I turn on the switch, I get no movement, no hum … nothing.
I'd like to think the switch is at fault … but I notice it has a capacitor labeled 7 pico Farad, 250 VAC (the unit is 120 … I'm just reporting what's on the capacitor).
Basically, it could be the switch (in which case I'll bypass it and have it run on high whenever it's plugged in), the capacitor (in which case I want to replace the capacitor), or the motor (in which case, I'll through it in the scrap bin).
Should I jam the leads of my multi-meter into the wires coming out of the switch to test? Or … test the capacitor somehow?
Thanks!
Best Answer
A capacitor is defined as two conductors separated by a dielectric. Consequently, there is no direct electrical connection between the plates or conductors. Current only flows to charge the plates by pulling electrons out of the dielectric.
So, on a good non-polarized capacitor, connecting your ohmmeter across the capacitor should show low resistance at first and climb to overload as the capacitor charges up to the voltage of the meter and resistance to current flow increases. Reversing your leads will then yield the same result.
A shorted capacitor will show zero resistance either way.
An open capacitor will show infinite resistance either way.