pool pump motor capacitor question

[b]

a friend is having problems with the pump in an outdoor pool.
Apparently the motor ran one day then the next day it would not come
on. mains supply is good. He suspects a capacitor - which seems to be
16uF 400v , from the motor. I've seen it, quite a chunky thing with a
small threaded screw coming out of it for attachment and a plastic
body. it's about the size of the mains filter caps in 1970s t.v.s

I had never seen a 16uF cap before, and I am surprised at this size.
Is it likely to be an electrolytic? I presume replacing this is a
good place to start. Any thoughts?
-B

 

[Jamie]

a friend is having problems with the pump in an outdoor pool.
Apparently the motor ran one day then the next day it would not come
on. mains supply is good. He suspects a capacitor - which seems to be
16uF 400v , from the motor. I've seen it, quite a chunky thing with a
small threaded screw coming out of it for attachment and a plastic
body. it's about the size of the mains filter caps in 1970s t.v.s

I had never seen a 16uF cap before, and I am surprised at this size.
Is it likely to be an electrolytic? I presume replacing this is a
good place to start. Any thoughts?
-B

IT's a AC (Non polarized cap) and you can't always assume a cap.
You can look for vented internals at the base ect.

Also a good test would be to see if the motor is humming when started.
if this is the case then the CAP maybe opened but I would first check
that. The caps are not cheap.

Use a CAP meter or your DMM which many have a C testing function.
check for DC shorts and then test for Value using a Cap function .

Also, some motors use a centrifugal switch that sits in the head of
the motor. The actuator/switch could be stuck or broke. You can
determine this
by using an ohm meter from the windings verses the other windings..

etc..


http://webpages.charter.net/jamie_5"

 

[Peabody]

b says...

a friend is having problems with the pump in an outdoor
pool. Apparently the motor ran one day then the next day
it would not come on. mains supply is good. He suspects
a capacitor - which seems to be 16uF 400v , from the
motor. I've seen it, quite a chunky thing with a small
threaded screw coming out of it for attachment and a
plastic body. it's about the size of the mains filter
caps in 1970s t.v.s

I had never seen a 16uF cap before, and I am surprised
at this size. Is it likely to be an electrolytic? I
presume replacing this is a good place to start. Any
thoughts?

In my experience when the start capacitor fails, the motor
will turn slowly, but never kicks up to speed. Some motors
also have a run capacitor.

The start capacitor on all 1 hp motors I've had was always
rated 161-193 mfd. Can't tell you what a 16 MFD would be.

 

[PeterD]

a friend is having problems with the pump in an outdoor pool.
Apparently the motor ran one day then the next day it would not come
on. mains supply is good. He suspects a capacitor

Why does he suspect it?

- which seems to be
16uF 400v , from the motor. I've seen it, quite a chunky thing with a
small threaded screw coming out of it for attachment and a plastic
body. it's about the size of the mains filter caps in 1970s t.v.s

I had never seen a 16uF cap before,

Limited experience?

and I am surprised at this size.

Too small or too large?

Is it likely to be an electrolytic? I presume replacing this is a
good place to start.

Good for the person who sells you a new capacitor. Probably not good
for you, however.

Any thoughts?

More information, what diagnostic work have you done yet?

 

[Smitty Two]

IT's a AC (Non polarized cap) and you can't always assume a cap.
You can look for vented internals at the base ect.

Also a good test would be to see if the motor is humming when started.
if this is the case then the CAP maybe opened but I would first check
that. The caps are not cheap.

About $7. Many people would call that cheap.

Use a CAP meter or your DMM which many have a C testing function.
check for DC shorts and then test for Value using a Cap function .

Also, some motors use a centrifugal switch that sits in the head of
the motor. The actuator/switch could be stuck or broke. You can
determine this
by using an ohm meter from the windings verses the other windings..

etc..

The centrifugal switch contacts on my compressor motor were
intermittent, and I ended up replacing the switch. But I don't consider
the few dollars I spent on new caps as a first attempt, to have been
wasted.

 

[b]

Smitty Two ha escrito:

The centrifugal switch contacts on my compressor motor were
intermittent, and I ended up replacing the switch. But I don't consider
the few dollars I spent on new caps as a first attempt, to have been
wasted.

thanks for the useful replies.- part of the problem here is that I'm
working 'blind' , not having seen the setup or been able to check it
out for myself, I don't even know what type of motor it is or how old
etc. All I've seen was the cap that was shown to me briefly. I'll try
and get out there to take a look for myself and post back. meanwhile
will follow up on the links and advice posted here.
cheers, B.