There are 2 wires coming from the motor into the capacitor do they need to be wired to a specific lug on the capacitor. From what I can tell the old capacitor and the new have no markings. The lugs on the old one are just straight fins and the new one has right angles one pointing down the other up. This is on a trades pro compressor that the lead to the capacitor came loose and consequently burned itself up as well as the lug on the capacitor. Marked the wires before taking them off the old capacitor so know where they came from.
Capacitor for a small compressor wiring question
- Thread starter Adohrn
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Techie1961
Well-known member
I'm looking forward to the replies on this one. I always make sure that I put the capacitors back the same way when I have to work on a motor. Every motor cap that I have seen has some sort of mark on it, usually a red dot or something like that.
Rookie2
Well-known member
nope its universal , just make sure its the same uf and voltage.
Much appreciated Rookie2. Definitely to nervous last night to plug anything in.
Bought the capacitor from same company that made the compressor. The voltage is the same but the uf I believe is like 145 and the original 140. It will be a few hours until I can check that though. All other specs are the same. Any reason to be concerned.
Bought the capacitor from same company that made the compressor. The voltage is the same but the uf I believe is like 145 and the original 140. It will be a few hours until I can check that though. All other specs are the same. Any reason to be concerned.
RPH
Well-known member
So long as it's an ac cap no problem. If it's a dc cap then polarity does matter. This one should be an ac capacitor.
Rookie2
Well-known member
I think 145 will work. Try not using extension cords with those compressors it really kills the starting ability.
the ac capacitors/condenser on a motor are for starting surge of the motor. the voltage rating marking on it are for max voltage rating. you can use higher rating voltage or little lower (and Never lower than your working voltage of your system +10%), but the capacitance in uf, I think if you use higher uf it won't help much , but won't hurt, bu if you use lower it will have problem starting the motor smoothly. polarity doesn't matter on AC capacitors. It will matter on DC
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gary300
Well-known member
All capacitors, except electrolytic ones (and they have polarity markings on them and are used for DC applications) are not polarity sensitive so you can just attach the leads in the most convenient manner. The difference between 140 uF and 145 uf is not significant. Capacitors have a very wide tolerance.
