Blown capacitor

[A16X]

I have an abac 150l 3hp fm3 pro compressor.....it should be run off a 20amp supply I believe but I've been running it on a 13 amp plug.
Today whilst sanding the capacitor started smoking and got very hot ( melted cover).
I had been sanding for a fair while and the compressor was running.

Would I have prevented the capacitor burning out if I'd been on my 20a supply?

 

[Barking Mat]

How old is the compressor? Caps do die, check the rating and eBay is your friend. I don't think the 13a as opposed to 20amp supply is to blame, but someone might be along to contradict that.....

 

[brightspark]

makes no odds what so ever if it ran ok on 13 amp without popping fuses on start up .

 

[Wozzaaah]

It sounds unlikely, the 13A fuse would be the weak link if it asks for a 20A supply.
More likely the cap was faulty or you ran it for too long.
Should be easy enough to replace the blown cap.

 

[brightspark]

running in on a thin extension lead wouldn't help if it was . running continuously on a light duty cycle comp could cook the motor

 

[A16X]

Ok thanks,so sounds like I just ran it for too long continuously......
How long would be deemed acceptable?

Is there any benefit to me relocating the compressor to make use of my 16a supply or should I just continue where it is?

 

[Anguz]

i would fit a new cap and see how long that one lasts..... if it fails quick i would consider moving it... but i bet it runs on and on

 

[Wozzaaah]

My little 50L direct drive one came to a grinding halt recently, it was the first time I'd fired it up in quite a few years.
I haven't bothered to see what's wrong with it yet.

As said, bung a new cap on it and see what happens.

 

[eSCHEn]

A common lifespan for a capacitor is only 1000 hours, as others have said it will have more than likely just died through normal use.

When you come to replace it you may be able to up the quality to a 2000 or 5000 hour unit. You can also increase the temperature and voltage readings without issue. Eg if the original is a 1µF 16V 0..70°C electrolytic then a 1µF valued electrolytic rated at 100V and -55..125°C will do exactly the same job but will cope with more extreme conditions.

But as Woz says:

bung a new cap on it and see what happens

 

[carbon]

More likely to be a metalized polypropylene rated at 450vac than an electrolytic for a motor run capacitor

 

[A16X]

Haha all this is a foreign language to me.......if I knew what you all meant I'd not have needed to ask the original question.
Thank you though for all the effort you've all gone too to respond!
I think I messed up as I bought a capacitor from a local source, they charged me £40! I think I'd have been better off finding another source?

 

[rtbcomp]

...
Today whilst sanding the capacitor started smoking and got very hot ( melted cover).
...

If there's one capacitor would it be a start capacitor?

If it was a start capacitor, would there be a centrifugal switch?

If a centrifugal switch failed to open would that cook the capacitor?

 

[carbon]

A lot of motors that I see only have the one cap and it's always in circuit with no switch

 

[A16X]

This has another unit of a similar size next to it but less wires......

 

[carbon]

Some have two caps in parallel but not sure if both are always in circuit on compressors.

 

[Anguz]

cap would have been cheaper from ebay

 

[A16X]

Probably but most of the writing was missing as it had melted in just the wrong place.

 

[carbon]

Sometimes if your lucky cap values are stamped on the motor data plate

 

[A16X]

Thanks Chris......I think they might be however I didn't really know what I was reading.

 

[Harry_Worth]

I have an abac 150l 3hp fm3 pro compressor.....it should be run off a 20amp supply I believe but I've been running it on a 13 amp plug.
Today whilst sanding the capacitor started smoking and got very hot ( melted cover).
I had been sanding for a fair while and the compressor was running.

Would I have prevented the capacitor burning out if I'd been on my 20a supply?

No, It would have made no difference!