motors, starting (pool motor!)
#7
Not directly woodworking related, but motors with starting caps are certainly involved and I know you guys know about these things!

Looking for your thoughts - 
I have a 1.5HP pool pump, trips the breaker on startup.
Makes a loud buzzing noise in the seconds before the tripper breaks.
After 6-8 tries (flipping back the tripped breaker) it does fire up and everything runs fine until the next morning when it tries to startup again.. Rinse and repeat.

Sounds like a bad starting capacitor? 
Is that generally a serviceable part or should I be looking for a new motor? It's about 8yrs old
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#8
I would pull the motor and check for bearing integrity.  If the bearings are tight or there's something binding, that'll make starting difficult.  You could also check running current against nameplate current.

But it does sound like a bad starting cap or centrifugal switch (stuck open).  I'm assuming it's a vented frame design, which most are, so that switch is in the weather even if rain can't get directly to it.  Most I've seen aren't even shielded against splashing, so a heavy rain can make the inside wet just from water splashing off the ground.  Lousy environment.

It's also possible, if the capacitor is shot, that it will start and run backwards, so do watch for that.

You may need to replace the breaker soon if you've cycled it a bunch of times with locked rotor current (could approach 100A at 120V) passing through when opened.  The arcing internally is chewing up the guts.

At least a new capacitor is cheap.  Does it only have a starting capacitor, and no run capacitor?  If it has a run cap, it's in the B-winding circuit all the time, and only the starting cap is cut in and out, so both of them are needed to start.
Tom

“This place smells like that odd combination of flop sweat, hopelessness, aaaand feet"
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#9
Thanks! 
I'm not sure if it has a run capacitor. I'll have to crack it open and look.
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#10
(08-23-2019, 09:51 AM)mound Wrote: Thanks! 
I'm not sure if it has a run capacitor. I'll have to crack it open and look.

If it's just a truncated oval can (in cross section), then probably not.  Unless it's a dual-value cap.  But I'm guessing not.  The ones I saw online when poking around just now seem to only have a start cap.
Tom

“This place smells like that odd combination of flop sweat, hopelessness, aaaand feet"
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#11
Update - $6 starting cap replaced in 5 minutes.. problem solved!
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#12
(08-26-2019, 08:27 AM)mound Wrote: Update - $6 starting cap replaced in 5 minutes.. problem solved!

   
Tom

“This place smells like that odd combination of flop sweat, hopelessness, aaaand feet"
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