Plug Fuse for Compressor

[nsclarke65]

Hi,

I have recently been given a compressor from my place of employment and after servicing it i started to use it. It all works fine except on about five occasions it has blown the plug fuse (13A) The compressor is single phase but i think the motor takes about 15 Amps which i think is blowing the fuse. Is there/can you safely use a higher rated fuse or will i have to wire the compressor through a heavy duty fuse box.

Please help

Regards Nigel

 

[breezer]

you cant get a bigger fuse for a plug.

how was it wired before?

 

[kai]

Buy a 1 way consumer unit with a 16amp MCB in it, and fed it through that method - should solve the problem.

 

[JohnD]

We seem to be guessing what the loading is.

Have you examined the compressor all over looking for the makers plate that says what the power requirements are?

 

[Big_Spark]

If it was manufactured with a 13A plug on it, then the maximum current draw should not exceed 13A, unless someone put a 13A plug on a machine that may require a 16A CEEFORM plug, but as has been said above...FIND THE PLATE AND CHECK THE RATING OF THE MACHINE

 

[nsclarke65]

Thank you for the replies.

When i got the compressor it wasn't being used and there was no plug on the lead. It was a bit nieve of me to think it was a household plug on the end!

I looked at the motor last night and it is 16 amps so which is best the 16A CEEFORM plug or a one way consumer unit with a 16 amp MCB.

Thanks again

 

[JohnD]

You need both.

A motor may have a start-up surge - if you buy a major maker like MK or MEM that supplies the industrial market as well as domestic, you can start out with a B16 and move to a C16 if it needs it (there are loads around on the used market like fleabay)

 

[TicklyT]

I've been there!..... The compressor I saw had a 1-1/2 Hp single phase motor. These will draw a very hefty current on starting, more than enough to pop a 13A fuse, even if the running current is supposed to be about 6 or 7 Amps quoted on the plate.
The manufacturers supplied it with a 16A connector fitted. They did not recommend connecting it via a 13A plug

There is usually a big capacitor connected to the starter windings of a single phase motor. It's job is to generate a temporary second phase from the single phase supply to kick the armature off into rotation in the correct direction. Once running it is disconnected by a centrifugal switch within the motor, and the current settles down to the running current.
To the fuse in the plug it looks like a short circuit as the capacitor charges when the motor is starting.

Traditionally motors used to be disconnected from their drive trains by a clutch so they could reach their operating speed quickly to reduce the problem.

 

[nsclarke65]

What excellent advice, thank you all very much.

I will now hunt around for the right equipment and then call an electrician to come and fit it for me.

Cheers again.