Motor start capacitor

[Peabody]

It's an old Sears garage door opener. The schematic shows a 50 ufd start
capacitor. What's in there now is 43-52 ufd. What I've found locall to
replace it is 53-64 ufd. Will that work?

 

[Fred Smith]

On 2017-10-27, Peabody <waybackNO584SPAM44@yahoo.com> wrote:

It's an old Sears garage door opener. The schematic shows a 50 ufd start
capacitor. What's in there now is 43-52 ufd. What I've found locall to
replace it is 53-64 ufd. Will that work?

Probably... But the wrong capacitor value may make the motor not
spin up at all, or go in reverse instead.

 

[M Philbrook]

In article <20171027-170008.854.0@Peabody.ssl.astraweb.com>,
waybackNO584SPAM44@yahoo.com says...

It's an old Sears garage door opener. The schematic shows a 50 ufd start
capacitor. What's in there now is 43-52 ufd. What I've found locall to
replace it is 53-64 ufd. Will that work?

YES
Those values are not critical for that application.

 

[Foxs Mercantile]

On 10/27/2017 6:18 PM, M Philbrook wrote:

In article <20171027-170008.854.0@Peabody.ssl.astraweb.com>,
waybackNO584SPAM44@yahoo.com says...

It's an old Sears garage door opener. The schematic shows a 50 ufd start
capacitor. What's in there now is 43-52 ufd. What I've found locall to
replace it is 53-64 ufd. Will that work?

YES
Those values are not critical for that application.

Right. A start capacitor has a minimum value at which it work work.
The ones that are critical are the run capacitors. And even then,
10-20% will usually work, 100% might, but the motor will run hot.

--
Jeff-1.0
wa6fwi
http://www.foxsmercantile.com

 

Peabody <waybackNO584SPAM44@yahoo.com> wrote:

It's an old Sears garage door opener. The schematic shows a 50 ufd
start capacitor. What's in there now is 43-52 ufd. What I've found
locall to replace it is 53-64 ufd. Will that work?

You might check with an HVAC supply place if you haven't already. A lot
of them carry Supco aftermarket start capactors, or have something they
can cross to Supco. Supco has one that is pretty close to what you have
now, and a few that might fit - all cylindrical, diameter x height:

CS43-56X110 43-56 uF, 110-125 V 1- 7/16 x 2-3/4
CS53-70X330 53-70 uF, 330 V 1-13/16 x 3-3/8
CS56-72X110 56-72 uF, 110-125 V 1- 7/16 x 2-3/4

I am not affiliated with Supco. I put one of their dual start capacitors
(fan and compressor) in the outside A/C unit at my old house and it
worked OK.

Matt Roberds