Bench Grinder Start Capacitor Specs

[JRJ61565]

I am currently working on restoring a bench grinder I recently picked up and am looking for some suggestions on finding a replacement start capacitor. After pulling it out, the markings were deteriorated, and I can’t make out any specs (I can’t really clean it off anymore without rubbing off the markings that are visible).

Grinder Specs:
Make: Walker-Turner
Frame: 118
Type: GR50
HP: 1/2
Volts: 110
Cycles: 60
Phase: 1
RPM: 3450
Amps: 5.2
Serial #: 132DD936393

Capacitor Markings: (What I can make out at least)
Dimensions: 5” x 5” x 3.25”
Markings:
PR Mallory & Co Inc
20?????D
?30 ??C
A205034-I

I uploaded photos of the grinder and capacitor in an album labeled "Bench Grinder Project" on my profile because the attachment buttons don't seem to be working. Not looking for this exact capacitor, just looking for a suitable replacement. Any info or suggestions are appreciated, Thanks!

(Also, if this isn’t a start capacitor, please let me know, I’d rather not blow something up based on my assumption…)

 

[Bert_]

20 mfd
Looks like 630v but that is a very high rating for a motor capacitor.

It's not a start capacitor but is a run capacitor.

I bet that one still works and may well outlast a new one.

 

[Wrench97]

20UFMFD
230 VAC

Probably a 20 UF @ 230 volt go higher on the voltage is ok but not lower So 20 MF 377 VAC or 440 VAC

 

[exmaxima1]

Capacitor Markings: (What I can make out at least)
Dimensions: 5” x 5” x 3.25”
Markings:
PR Mallory & Co Inc
20?????D
?30 ??C
A205034-I

I can't imagine a grinder capacitor being 5 x 5 x 3-1/4 inches. That is HUGE, and if it is only 20uF then it has to be a paper/oil type and engineered as a run cap

 

[JRJ61565]

Looks like 630v but that is a very high rating for a motor capacitor.

It's not a start capacitor but is a run capacitor.

Yeah, 630V is what I initially thought the first number was when I looked, but I thought that that was super high for a 110V grinder.
And thanks for correcting me on the start/run capacitor.

20UFMFD
230 VAC

Probably a 20 UF @ 230 volt go higher on the voltage is ok but not lower So 20 MF 377 VAC or 440 VAC

So would something like this 'Goodman CAP200000440RPP' (Don't have enough post to post a link yet) fit the bill? Just want to make sure I'm reading all the specs right.

I can't imagine a grinder capacitor being 5 x 5 x 3-1/4 inches. That is HUGE, and if it is only 20uF then it has to be a paper/oil type and engineered as a run cap

Yeah, she's hefty alright...

 

[Wrench97]

As long as it physically will fit I think it'll work 630v is pretty rare in 20 uf.

Here are some at Grainger the Titans are a tad better then the Dayton brand.

https://www.grainger.com/search/mot...trs&searchQuery=capacitor&sst=4&tv_optin=true

 

[JRJ61565]

As long as it physically will fit I think it'll work 630v is pretty rare in 20 uf.

Here are some at Grainger the Titans are a tad better then the Dayton brand.

Awesome, good to know.

And thanks to everyone for the help and input, I appreciate it!

 

[BillK]

because the attachment buttons don't seem to be working.

I think you have to have 5 posts, maybe 10 before you can add attachments.

That is one big capacitor You might want to send an e-mail to Mouser electronics and see if they can cross the Mallory number. I am thinking I have an ancient Mallory catalog at home somewhere but not sure if I can find it or not.