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Motor starting switch

O

Oppie

Jan 1, 1970
0
pain in the tail, my FAIP H150 electric power washer died. The motor
starting capacitor went (oozed out the side of plastic shell). Replaced it
with a similarly rated phenolic case starting cap but noticed it's getting
very warm. More than likely the motor centrifugal switch is stuck closed. It
is a TEFC motor so getting to the switch is a major pain. Not to mention
that I don't see a replacement part listed anywhere.

As a test, I started the motor and then pulled a lead from the starting
capacitor. It sparked, showing that there was current flowing. So, either
this is a permanent split capacitor motor (unlikely) or the centrifugal
switch has failed shorted.

Now looking for a simple electronic or magnetic replacement. Has anybody had
any success with a similar replacement? My first thought was the starting
relay commonly used in refrigerators and air conditioners. It has a current
sensing relay coil in series with the run winding. Initially when power is
applied, the rotor is stationary and the run winding current is high. This
closes the contacts and applies power to the start winding (usually no
capacitor used on this) and motor starts. When the motor is up to speed, the
start current diminishes and the relay drops out, removing power from the
start winding.

Thank you as always - Oppie
 
O

Oppie

Jan 1, 1970
0
Correction - it is FAIP model H120.
That's what I get for doing something from memory at my age...
 
K

Kevin McMurtrie

Jan 1, 1970
0
"Oppie" <[email protected]> said:
pain in the tail, my FAIP H150 electric power washer died. The motor
starting capacitor went (oozed out the side of plastic shell). Replaced it
with a similarly rated phenolic case starting cap but noticed it's getting
very warm. More than likely the motor centrifugal switch is stuck closed. It
is a TEFC motor so getting to the switch is a major pain. Not to mention
that I don't see a replacement part listed anywhere.

As a test, I started the motor and then pulled a lead from the starting
capacitor. It sparked, showing that there was current flowing. So, either
this is a permanent split capacitor motor (unlikely) or the centrifugal
switch has failed shorted.

Now looking for a simple electronic or magnetic replacement. Has anybody had
any success with a similar replacement? My first thought was the starting
relay commonly used in refrigerators and air conditioners. It has a current
sensing relay coil in series with the run winding. Initially when power is
applied, the rotor is stationary and the run winding current is high. This
closes the contacts and applies power to the start winding (usually no
capacitor used on this) and motor starts. When the motor is up to speed, the
start current diminishes and the relay drops out, removing power from the
start winding.

Thank you as always - Oppie

Maybe there's no switch. If so, you need a run capacitor rather than a
start capacitor. Start capacitors are aluminum electrolytic while run
capacitors are plastic film. Electrolytic capacitors produce gases at
high currents and they'll explode without a long resting period.
 
M

Martin Riddle

Jan 1, 1970
0
Not sure if they still are around but there used to be a solid state job
(Probably a brimistor or such). You just wired it in series with the
start winding and it went open in a short period of current flow.

I have seen those Bimetallic PTCs? in the little cheap fridges.
They usually fail after a few years. But they have the desired mode of
operation.

Cheers
 
O

Oppie

Jan 1, 1970
0
Tim Wescott said:
That means it works fine for you, but when your brother-in-law borrows it
the thing comes back broken.
Yes. I'd sooner put in a 1 second time delay relay that opens the start
circuit after the time delay.
 
O

Oppie

Jan 1, 1970
0
Martin Riddle said:
I have seen those Bimetallic PTCs? in the little cheap fridges.
They usually fail after a few years. But they have the desired mode of
operation.
Chuckle... I repaired the next door neighbor's refrigerator this August. One
horrible time of year (in northern hemisphere) for it to die. It had a PTC
in the starting circuit in series with the start capacitor. A bimetal
overload switch would open the line feed when there was a fault or short
cycle (where the compressor tries to restart under load). The PTC failed and
burnt up rather dramatically!
New starting module and capacitor from allappliancepros.com plus overnight
shipping for $105 and neighbor was very happy to have it working again. Now
he knows to vacuum the condensing coils once a year as the failure was
largely due to them being totally clogged.
 
O

Oppie

Jan 1, 1970
0
Kevin McMurtrie said:
Maybe there's no switch. If so, you need a run capacitor rather than a
start capacitor. Start capacitors are aluminum electrolytic while run
capacitors are plastic film. Electrolytic capacitors produce gases at
high currents and they'll explode without a long resting period.
Duly noted. Thank you for the explanation. I was not aware of the
difference. Trying to confirm whether it has a centrifugal switch and making
the appropriate choice.

I did run the motor albeit without water pressurization loading. After motor
was to speed, opened the capacitor circuit. There was no loss of speed when
the capacitor was opened. I should repeat the test with hydrostatic load.
The motor is a Nord and must have been a custom for FAIP. I haven't been
able to get an answer from FAIP or whomever purchased them.

Regards - Oppie
 
On Saturday, October 12, 2013 3:23:00 PM UTC-4, Oppie wrote:

That model uses an 80MFD 250VAC capacitor which is within the realm of a PSC motor value, there is no centrifugal switch or any other kind of start winding cutout, the start winding remains in the circuit permanently. Just spend the $22 on FAIP part no. MECO61695 and be done with it.
 
B

bud--

Jan 1, 1970
0
Duly noted. Thank you for the explanation. I was not aware of the
difference. Trying to confirm whether it has a centrifugal switch and
making the appropriate choice.

A run cap of the same value, if I remember right, is significantly larger.

And if there is a start switch that does not open I would expect the
start winding would overheat and fail. If there is a start switch and it
is not opening the previous failed start cap may have protected the winding.
 
The new thing is called a "Stearns Sinpac" switch. You may

be able to get them from Grainger or McMaster-Carr.

It is an electronic replacement for the potential relay

used in larger hermetic compressors, as well as the older

thermal starting control on small refrigerators.

Just Google "sinpac switch" and you'll get the manufacturer's

main page on this device, then you can dig for a local

distributor of them.

Absolutely wrong technology for a high frequency ON/OFF cycle app like a pressure washer. His motor is a PSC anyway.
 
O

Oppie

Jan 1, 1970
0
On Saturday, October 12, 2013 3:23:00 PM UTC-4, Oppie wrote:

That model uses an 80MFD 250VAC capacitor which is within the realm of a
PSC motor value, there is no centrifugal switch or any other kind of start
winding cutout, the start winding remains in the circuit permanently. Just
spend the $22 on FAIP part no. MECO61695 and be done with it.

Thanks for the reality check!
Thought I could get a grainger part similarly rated (of course "similarly
rated" was open to conjecture). So, I spent $16 on the grainger cap but
didn't have to pay for shipping...

My original thought was as Bud noted, the capacitor failed because the
starting switch was stuck closed. I've had lots of motors with starting
switches fail stuck and you can hear the difference when the start wining is
energized. Leave it on too long and the start winding fries. That happened
on one of our lathes. The operator thought Gee this motor's got more balls
today and I can take bigger cuts... right up to the point where the motor
smoked (found that since it was 'nuisance tripping' he had upped the current
trip level). Since then, I've been trying to use a better current sense with
something like a Siemens 48ATD1S00 to replace the OEM current relay.
 
[email protected] wrote:





Don't most pressure washers just let the motor run, and limit pressure

with a relief valve? Or is that last decade's technology?

Yes, of course, if it is PSC, then no starting control is needed.

I had to trust the OP's description of the motor, which apparently was

wrong.



Jon

Some do and some don't. Some have a pressure actuated switch that cuts power to the motor whether the operator is holding the power switch (usually a momentary) ON or not (Karcher), some don't. Regardless, the operator will be constantly turning the thing ON and OFF in normal use too. So thermal cutouts are not used here. And yes, most of them use bypass relief pressure regulators.
 
Thanks for the reality check!

Thought I could get a grainger part similarly rated (of course "similarly

rated" was open to conjecture). So, I spent $16 on the grainger cap but

didn't have to pay for shipping...



My original thought was as Bud noted, the capacitor failed because the

starting switch was stuck closed. I've had lots of motors with starting

switches fail stuck and you can hear the difference when the start winingis

energized. Leave it on too long and the start winding fries. That happened

on one of our lathes. The operator thought Gee this motor's got more balls

today and I can take bigger cuts... right up to the point where the motor

smoked (found that since it was 'nuisance tripping' he had upped the current

trip level). Since then, I've been trying to use a better current sense with

something like a Siemens 48ATD1S00 to replace the OEM current relay.

You can find the exploded parts diagram and part number list for all the FAIP stuff all over the web. There is no centrifugal switch, no potential relay, no nothing to cut the start winding out. The ON/OFF switch, Swiss made by DiSA, has the thermal protection, a M1630FV 12.5A T1, means a 12.5A fastthermal cutout, two pole single throw ( looks like one ea for run and start windings ), spring loaded momentary. There is more to the cap than just rating, it has a form factor and a grommet to waterproof the fast-on connection. If you don't have a waterproof fit, anything could happen.
 
O

Oppie

Jan 1, 1970
0
You can find the exploded parts diagram and part number list for all the
FAIP stuff all over the web. There is no centrifugal switch, no potential
relay, no nothing to cut the start winding out. The ON/OFF switch, Swiss
made by DiSA, has the thermal protection, a M1630FV 12.5A T1, means a
12.5A fast thermal cutout, two pole single throw ( looks like one ea for
run and start windings ), spring loaded momentary. There is more to the
cap than just rating, it has a form factor and a grommet to waterproof the
fast-on connection. If you don't have a waterproof fit, anything could
happen.

Haven't found much for the H120 on the web. Even the FAIP-NA
(www.fna-group.com) site doesn't have it. I erroneously referenced a H150
as that was the only one for which a user manual could be found. I think I
found something similar in a Husky P1600
 
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