208-230 V single phase pool pump- start capacitor 165V?


Old 05-30-17, 10:17 AM
Thread Starter
Join Date: Jan 2004
Location: United States
Posts: 1,182
Received 0 Votes on 0 Posts
208-230 V single phase pool pump- start capacitor 165V?

So the capacitor is bad and going to swap in new one. The old one is rated 108-130MFD 165V. Grainger doesn't have one in 165V. The pump is rated 115/208-230V. It has a switch under cover to switch between 115V and 230V and it is set at 230V position. It is wired for 240V.

My other pump is similar in that it is rated 115/230, with a switch under the cover which is set at 230V. It is wired for 240. The capacitor on it is rated 161-193 MFD , 110V.

I am confused how these capacitors can be rated lower than the line voltage? These were purchased new years ago so this is how they came from factory and have run fine till now.
Old 05-30-17, 11:43 AM
Join Date: May 2015
Location: USA
Posts: 3,138
Received 2 Votes on 2 Posts
They can be rated lower than full line voltage because they are in series with the winding in the motor and much of the line voltage gets dropped across that winding. Exactly what voltage the cap will see depends on the design of the motor, but you will always be safe using a higher voltage rated cap than the original. I would not go lower.

Thread Tools
Search this Thread
Ask a Question
Question Title:
Your question will be posted in: