On Fri, 25 Aug 2017 14:56:50 -0700 (PDT), wrote:

On Friday, 25 August 2017 19:33:59 UTC+1, wrote:
Well, this morning the phase converter won't start at all. There is
a button that can be pressed that energizes the contactor that
connects the 10 starting caps to the motor. This button bypasses the
time delay relay that energizes the contactor. Pressing the button has
no effect at all, the motor just hums.
I don't know yet if the contactor is pulling in or not because I
cannot see into the electrics enclosure while throwing the breaker
that turns on the phase converter. Even though I can press the bypass
button while throwing the breaker I cannot see the contactor. I'll
have to get another set of eyes to look inside while I turn the
converter on.
Getting on subject, I have a DVM that has a capacitance measuring
function. Measuring half a dozen known good oil filled caps the
readings on the meter match very closely, within one MFD, the value
printed on the caps. If I measure the caps in the phase converter and
they measure close to the value printed on the case does this mean the
caps are probably good? Is there another test I can perform with the
meter? And since there are 10 starting caps connected in parallel
could just one or two bad caps cause the starting problem?
Thanks,
Eric

AIUI you could have cap(s) leaking or a faulty switch contacts. Soldering a wire to short the starting switch could tell you which. Obviously don't power the motor for 5 seconds like that.


NT
Soldering a wire across switch contacts won't work easily because the
switch is a contactor. What I'm gonna do is get someone to look at the
contactor when I turn on the breaker to see if it pulling in. If it is
pulling in then I'll remove it and check the contacts. Then replace
them if need be. If the contactor doesn't pull in then I'll need to
find out if the coil is bad or if it isn't getting power. I will still
need to check the caps if the contactor is working properly.
Eric