Motor Start Capacitor help

[pre67]

hi my compressor has always been a pig to get started and i have just been reading this thread

http://www.mig-welding.co.uk/forum/showthread.php?t=33098&page=2

and i think its the cap that's gone on mine so im going to order one as there only about a 10er but im unsure what one to order because i cant find one the same spec as mine its 85uf +5% 250v ac dose the spec really matter that much?

 

[shenion]

As long as it is 250V or higher it will work.

You can probably get a close value, 90uf may be fine. Smaller will reduce start torque.

 

[pre67]

cool cheers for the help man
these to are the closets i can find witch do you think i should go for?


http://www.ebay.co.uk/itm/80uf-100u...al_Components_Supplies_ET&hash=item3cb3f8ce7e

http://www.ebay.co.uk/itm/80uF-Moto...al_Components_Supplies_ET&hash=item3365fe7e64

 

[eil]

The second one if you definitely cant find a 85uf, the first one is a start cap and yours looks like a run cap.

 

[pre67]

:S o right whats the difference between a run cap and a start cap ?

 

[shenion]

A start cap is only rated for intermittent use (while starting). A run cap is rated for continuous use.

 

[pre67]

Ok haw can i find out what mine is? or if i just get a run cap will it be ok even if its meant to have a start cap?

 

[Cobbler]

Hi there,
I have had to change several over the years on various bits & pieces, just take it to a local rewind or motor specialist, quite likely they will have a box of used ones for not much money, as they fit new when refurb the motors. If not they will have a replacement to match it. Last one I needed was about a year ago & was under a tenner. I wanted one for a shredder & the manufacturers wanted £80 for it, shredder was about that new. Went to the motor rewinders, charged me £6, when I told him the manufactures price he said their having a laugh!

 

[pedrobedro]

I bought one from a local electronic firm for a pressure washer I got out of a skip. It cost me £7. I just took the old one in and showed it them and they sold me the equivalent although the new one is physically a lot smaller so I had to gaffer tape it in

 

[eil]

Ok haw can i find out what mine is? or if i just get a run cap will it be ok even if its meant to have a start cap?

A run cap will do both
http://www.capacitor-manufacturer.com/CBB60-D3.htm
Like Shenion said a start cap is only in circuit for a few seconds if left in circuit like a run cap it will go pop.

 

[usmcruz]

Thats correct a start cap drops out shortly after. Never ever go down in microfarads. If its 85, stay with 85. Going down in microfarads will put undue stress on your compressor, and head it for a burn out. Get a universal cap if you cant find an 85, and use jumpers to get your 85

 

[pre67]

well since i had a little play with it seem to be working fine now

I had to spin the cap around to see the label and it must of been a dirty connection or something so im going to take it all to bits and cleen it all up and see

but cheers for the help any way guys i know what to get now if i do need one