I'm finally getting around to building a RPC, for the present at least to power a Bridgeport M I've been restoring. The BP motor is 1/2 HP, 3P with a nameplate voltage of 208-230 volts.
My workshop power measures 240 volts 1P.
Now that I'm taking a closer look at the "parts" I've accumulated, I have a few issues I'd appreciate someone "looking over my shoulder" on . . .
1. Idler motor is a relatively new 5HP 3P listed as 208-230 volts. I wouldn't think 4% overvoltage would matter, but worth mentioning. (Yeah, I know, greatly oversized for the intended load. First: it was a "gift" and Second: who knows what the future will bring . . .)
2. Motor starters I was planning to use are NEMA 1 (idler) and 00 (BP) C-H's, but both have 208 volt coils. Do I need to change the coils to 240 volt ones?
3. I was planning on employing a start capacitor with a delay timer to drop it out after a few seconds of starting. I've seen designs using an OFF delay timer. However, I've got quite a few ON delay timers sitting around not doing anything (and no OFF's) . . . with NO & NC contact pairs. Can't I use an ON delay, wiring to the NC contacts, and timing them to open to drop the capacitor? Am I missing something? Also, can someone give me a guideline on needed ampacity of the timer relay for dropping a starting capacitor?
Would appreciate any and all comments and suggestions!
Thanks
Paul
My workshop power measures 240 volts 1P.
Now that I'm taking a closer look at the "parts" I've accumulated, I have a few issues I'd appreciate someone "looking over my shoulder" on . . .
1. Idler motor is a relatively new 5HP 3P listed as 208-230 volts. I wouldn't think 4% overvoltage would matter, but worth mentioning. (Yeah, I know, greatly oversized for the intended load. First: it was a "gift" and Second: who knows what the future will bring . . .)
2. Motor starters I was planning to use are NEMA 1 (idler) and 00 (BP) C-H's, but both have 208 volt coils. Do I need to change the coils to 240 volt ones?
3. I was planning on employing a start capacitor with a delay timer to drop it out after a few seconds of starting. I've seen designs using an OFF delay timer. However, I've got quite a few ON delay timers sitting around not doing anything (and no OFF's) . . . with NO & NC contact pairs. Can't I use an ON delay, wiring to the NC contacts, and timing them to open to drop the capacitor? Am I missing something? Also, can someone give me a guideline on needed ampacity of the timer relay for dropping a starting capacitor?
Would appreciate any and all comments and suggestions!
Thanks
Paul
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