3HP compressor (for spraying) keeps blowing 13A fuse - help?

[gidon]

Following a very helpful chat with Chris, I've decided to have a go at spraying and have gone the compressor / HVLP (well actually RP) conversion gun route.
The compressor is this one:
http://www.axminster.co.uk/product.asp? ... e=1&jump=0
It comes with a 13A plug but keeps blowing the fuse when starting up. If I empty the tank it will usually start up ok, but that's no good when spraying because the pump will keep kicking in even with the tank full.
Axminster recommended a 16A supply but this isn't possible / practical at the minute.
Is there ANYTHING I can do. It's only the starting current that's the problem. Is it possible to get 16A fuses if that's not silly question (which I'm sure it is!) Could I install a bit of 20A fuse wire in the plug? Or is that just dangerous?
Appreciate any comments / advice.
Many thanks
Gidon

 

[CHJ]

gidon, in the past I have had 13amp (1" X 1/4") slow blow fuses but for the life of me can't remember where I got them from. Using bigger rated fuse wire is not safe as you may be exceeding the rating of the equipement supply cable or connections which could overheat in fault conditions.

As a temporary work around do you have a long extension lead? if so uncoil it and feed compressor through that and see if it causes enough volt drop to reduce surge.

 

[OllyK]

I have 16A supply in my shop, I'd be happy to take it off your hands for you

Did it come with the blue 16A plug on it or a standard 13A?

 

[gidon]

Thanks chaps. Been looking for these slow blow fuses but can't find 13amp 1 inch one only lower amp 20mm ones?
I've tried it on an extension lead but no joy unfortunately.
Olly no it came with a 13a plug. Axminster sent me a blue plug free but don't have 16a supply in my shed . Kind offer - thanks!
Cheers
Gidon

 

[Digit]

If I empty the tank it will usually start up ok,

Having serviced a hell of a lot of compressors in my time Gidon that sounds to me as though the unloader isn't working.

Roy.

 

[gidon]

Thanks Roy.
Come to think of it - it was turning itself back on again before - but now it just turns over really slowly and then cuts out. And this is blowing the fuse.
I temporarily put a 30A fuse wire in the plug oops - and still the same problem. I have to release all the air for it to start again. When it tries turning over it measure 20A(!!) on my tester jobby.
So I'm not sure now what to do - Axminster said it's a problem of electricity supply in my area. And other comments under review on their web site seem to mention this.
But maybe it's just faulty? It it be the oil they supply also?
Anything else I can test?
Cheers
Gidon

 

[wizer]

This is a worry, that compressor is on my xmas list

 

[Digit]

If I was still a wage slave Gidon what you're telling me would have me checking the unloading system.
The statement by Axminster is suspect. The current at start up, (tank empty) should be exactly the same as with with a more or less full tank.
That's what the unloader is for!

Roy.

 

[gidon]

Thanks Roy - anyway I can check the unloader?
Maybe the ones reported not to work just have faulty unloaders?
Could the cold weather be a problem? I'm leaving it running just now with the air coming straight out and will see if I still have the same problem.
Cheers
Gidon

 

[Digit]

Do you really want to Gidon? 3HP seem an expensive way to do some spraying.
I just checked the Axminster pic, you see the pipe that runs from the tank to the cylinder head?
If the thing's been in stock for some time and has been doing this from new it's logically either stuck or wrongly assembled. If it's new and you dismantle anything you could blow the guarantee, if it's stuck, clout the top of the cylinder where that pipe enters the cylinder head with a rubber mallet or similar and see if that will free it.

Roy.

 

[mailee]

Aw my God! :shock: This is exaclty the same compressor I have but under the Sealey label. I bought mine brand new and it also did exactly the same thing, well in that it wouldn't switch off. (Mine didn't blow fuses) I sent it back under warranty and they sorted it out. Apparently it was a faulty valbve in the head or so they stated. It was about a week in repair but now works fine. Looks like there is a batch with some faults.

 

[Digit]

That valve, Mailee, is the unloader valve. A compressor attempting to start up against the tank pressure would need a much larger motor and a lot more current to do the job, the unloading valve is a means of getting around that difficulty.

Roy.

 

[jonny boy]

Gidon, if you don't want the hassle of installing a fixed 16 or 20 amp supply, then i'd say try to get Axminster to swap it for a 2hp which should run on a standard 13amp outlet. Fault or no fault with the compressor, a three horse one will draw too much on start up for a 13amp outlet really.
cheers,
jon.

 

[gidon]

Digit - tried that - thanks. Didn't work (the clouting that is). Well i use the compressor for other things too - the 3HP ideally gives me the ability to do spraying without having to buy another box .
Mailee - interesting - thanks. There's a SIP machine too which looks similiar: http://www.worldofpower.co.uk/acatalog/ ... ssors.html (the 3HP one)
I think I'm going to swap it either for another Axminster or the SIP/Sealey. Reassuring that it doesn't blow 13A fuses. Do you use your for spraying? Is it up to it? What gun do you use with it?
Jon - I want the 3HP to run a conversion spray gun - 2hp won't do it. I already have a 1.5HP compressor (an Italian made Cosmo one). But I think I will still need to sort something with the fuse.
Cheers
Gidon

 

[jonny boy]

What do you mean by conversion gun?
jon.

 

[Digit]

Fair enough Gidon, if you don't know what you need nobody does.
You can get around the 13amp problem if you wire into a switched spur or cooker box and connect to a twenty amp MCB.
Perfectly safe and legal, no insurance problems either.

Roy.

 

[jonny boy]

If you do go with the cooker box, you must get the motor rated class 'c' MCB.
jon.

 

[Digit]

Jon's correct and you should be able to get one from any local electrical supplier to the trade. They are not expensive and if you have any problems the counter staff are usually most helpful.

Roy.

 

[Jake]

A 3hp motor is around 2.2kW, it should be fine on a 13A plug if it is working properly.

 

[Digit]

A 3hp motor is around 2.2kW, it should be fine on a 13A plug if it is working properly.

Absolutely! But if it's trying to start against a load then 13amps may be insufficient, which of course brings us back to the unloading valve. Why Axminster supplies it with a 13amp fitting then seem to imply that a 16amp circuit is required seems a little odd.