I'm taking apart a ceiling fan to get the motor. The only other components besides the motor is a switch and 2 capacitors. To get to the motor I have to cut the wires to the capacitor and I don't know how/if I should do that. So:

The fan has been disconnected for several days. The capacitor has three wires attached, purple brown and grey. The capacitor has the following diagram

"--Grey---4microF--| |-----" And "--Purple-4.5microF-| |----" Going into a node and "----------brown" leaving the node

The only other marking on the capacitor says 250 WV.AC. I've never seem a W here before.

Any help?

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    \$\begingroup\$ The capacitor is not dangerous. The motor won't work without it. \$\endgroup\$ – Charles Cowie Aug 20 '16 at 2:43
  • \$\begingroup\$ The "W" in WVAC probably means "Working" - the capacitor may be safely used on up to 250 V AC circuits. \$\endgroup\$ – Peter Bennett Aug 20 '16 at 2:46
  • \$\begingroup\$ I don't care if it works, but it won't discharge if I cut any of the wires? \$\endgroup\$ – BoddTaxter Aug 20 '16 at 2:46
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    \$\begingroup\$ At that capacitance, even if you cut the wire when it was connected to mains (not a good idea!) and even if that occurred at the peak of the AC waveform, at 4uF, there would be less than 0.2J of energy stored. Enough that you might feel it, but nowhere enough to be dangerous. \$\endgroup\$ – Tom Carpenter Aug 20 '16 at 2:52

The capacitor is not dangerous when the fan is unplugged and has been off for a while. The type of motor in the fan uses the AC frequency to run, and when everything is balanced has zero torque at zero speed. The capacitor unbalances the winding so that there is torque at low speed. It is usually switched out once the motor gets going, since it decreases efficiency if left in the circuit during normal operation.

If the cap is switched out of the circuit at just the right time, it could be left with high voltage on it. Depending on the cap type, it could retain that voltage for quite a while. Leakage should have discharged it over several days, but I'd probably quickly short with with a screw driver or a wire before touching it anyway.

WVAC stands for "working volts AC".

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