Hi all,

I'm after a single phase compressor, budget £600... What's good and what's not?

I'm looking at this Clarke one at the mo, http://www.machinemart.co.uk/shop/pr...air-compressor

Thanks, Yodi

 

what supply power supply you got?

 

Clue is in the first line

 

no it isnt you just put your not on 3phase. Have you got a 13amp, 16amp or 32amp supply?

 

How do you find out, as I'm interested in this as I'm on the look out for a compressor.

I have a fuse in the main fusebox in the house marked as garage, will that give any clues?

 

Sorry I put single phase as thats all I thought that counted, no idea but I know my plug sockets are on a 32 amp ring?

How about this one ?

http://www.ebay.co.uk/itm/Compressor...item336e4fd560

 

If your just on 3pin plug it's 13 amp as for finding anything else owt mate i'm lost as i'm not a sparky lol but on the compressor he put the link up for needs a 16amp minimum feed

 

needs 30amp not 16

 

Clark are over rated and can be difficult to obtain parts for,seally are overpriced...ERP are a really good make and based in hull..£600 should get u a decent machine,ones on british built air tanks are better than the italian crap the more you spend the better machine you will get mate..

 

Thanks for the advice, £600 really is the budget I'm looking to spend I'd gladly spend that on a used one to get a better compressor

 

It's beneficial but not essential

 

the clarke industrial ones like he,s looking at are built in the uk parts are massivly availiable on the industrial ones

 

Ah really, so what sort of current draw does it pull then?

My electricians coming tomorrow to see if its ok to run it and if I have space, I have a 4ton 2 post ramp on the plug cicuit so can't add the compressor to that too.

 

i know people that run that comp on a 13amp plug 16 works but obviously 32 is ideal. They are a good comp

 

Not true matey,we have stopped fixing them as we kept struggling for spares as they never had them in stock..they arnt a bad machine but aftersales can be lousy

 

Cheers mate, relieves some stress about the electrics then.... I can't find any info online but what is actually recommended for them as a minimum ?

 

how strange? They usually have shitload's of stock availiable.

 

30 amp is recommended as it's 3hp, i personally wouldnt run anything less but some have and got away with it some have and havnt. Where you based?

 

Got mine (3hp) running ok on a 20amp circuit though it is a motor rated mcb

That said its temporary till other garage is built and wired as I want

 

I'm in Potters bar, Machine mart says that one has a 4hp motor not 3

http://www.machinemart.co.uk/shop/pr...air-compressor

 

Only buy 4hp mate id your supply is top notch.a louzy supply will not run a 4hp long and u will run into problems with motors running at high amps witch will eventually burn out..3hp is your best bet,i wont sell a 4hp at work as they can be a ball ache

 

Aye up Dakar still knocking them compressors out then mate....

 

Hell yeah Daz

 

Oops too late, now in my garage

18 cfm
200 Litre
10 bar
4hp

 

http://www.machinemart.co.uk/shop/pr...air-compressor
I got one of these and i have it linked to fill a 300 lt tank to
I change oil once a month

 

Will be ok mate as long as you got a good 30 amp supply

 

Unfortunately I got bumped and the motors burnt out

 

what do you mean mate?

 

The motors burn out and doesn't work, it pops 32 amp breakers of b,c and d ratings..

I took the cover of the wiring off, its own circuit breaker has been bypassed and you see a huge arc in the motor if you try and turn it on

 

ring them up get somebody out

 

it's used mate not brand new

 

Your best bet is to buy a smaller motor.

The issue isnt so much with the 16/32A fuse rating. It's largely down to the size of the supply into the house, cable diameters and volt drop.

If you try and run a huge load of a small cable, the volt drop will be higher, and this in turn increases current draw. And motors starting up draw a lot of current unless there is an inverter or other similar soft start control.

Even a 3HP motor off a 13A outlet, either plug/spur or direct connection will still blow the fuse on startup quite often unless it has a good power supply ( ie cable size ), and if it does survive, the actual switch or plug will melt over time.

You could have what is called a 32A supply from a 2.5 ring....but what feeds the garage ? What cable diameter etc ? How long ? Plus What supplies the house ? Cable diameter etc.
Having a large diameter at the end of a circuit is pointless if it has a long and tiny cable feeding the start.

For any normal domestic household on single phase, 3HP is the absolute max you should consider, and you need a good sized supply conductor direct from source to the power outlet for the motor.
I didnt say cable direct...as naturally it may involve an additional consumer unit etc. But conductor size needs to remain IMO capable of 63A or more until the final dedicated circuit to the compressor. Which even for 3HP, needs to be at least 4mm^2, or better 6mm^2 and a 16A blue 3 pin plug or direct on/off isolator

Even then, when the motor kicks in, lights in the house can likely flicker, and some fluorescent style lighting can knock off and restart.


Another option which will help, is if you can get a soft start setup for it. This will reduce current draw on startup. Although actual running current can still be high.
Ive googled and there are some available, although Ive never used one myself.

Something like this, no idea on cost though. You'd need to speak to someone with more experience though to check actual suitability

http://www.schneider-electric.co.uk/...istart-01.page

 

Thanks for your help mate, the compressor is in an industrial unit and all the wiring is new and well up to the job.

I just worry about a new motor and it not fitting or being wrong and then have all the added hassle.

 

Steve you sound like you know the dance, my garage is fused in the houses fusebox with a 60amp fuse, I know you can't say for definate but do you think I would be ok with a 2.5hp 7.5 amp compressor, its a new item I've found on ebay. I presume this would go on a standard 3 pin plug?

 

Then take the motor off and take it a place that refurbs or rewinds them. They can either repair or source a replacement. Motors are fairly universal things. They can also test if it works.

And just because it is in an industrial unit, means nothing.

I worked as a spark for around 15 years, and some of the things you see people using are unbelievable. Whether just shoddy work, or undersized cables, terminations, etc etc

Unless you have a minimum of 6mm^2 from the incoming Electric Board mains to the compressor connection point itself, then IMO it is not sufficient.

At the minute you still dont know why the unit doesnt work. Just that it doesnt work, and internal parts had been tampered with.

 

Stu 7.5 am would be more than ok on a 13amp plug...

Stevie and jenrst, do you really think I should change the motor to a spec down and get a 3hp one?

 

We posted at the same time, the electrician told me also its the motor they are £160 new is it really worth trying to get that one repaired?

Should I see if I can get a 3hp one instead, any idea what fits? Thanks for your help

 

But what is the house supplied with ? How long is the cable run from incomer to garage ? What cable diameter ?

These are the important parts.

You could put 60A fuse after 60A fuse. But if the original incoming supply is only capable of 60A too....then clearly you're fighting a losing battle.

It would be like having ten fire hoses to extinguish a fire.....except they are all fed by a single fire hose at the origin. So by the time it gets to the outlet, it's just a dribble.

Fuse ratings dont indicate what a power circuit has to offer. They are purely protection for the wiring itself so the fuse should blow before wiring goes on fire.

2.5HP "should" be ok. But again, you cant overlook starting current. That's what will blow the fuse, not the normal 7.5A running current. And again, if the actual power supply is limited by cable size ( again, see volts as water flow in above ) then that current will rise.

But it's an easy fix to install an isolator with either a separate fuse or motor rated breaker. Or you could rely on the fuse at the fuse box.
Again, the fuses are not to protect equipment, they are primarily to protect wiring, or short circuits/fire risk.
Using a 13A plug, this will be the highest risk area for the current passing through. I did run one for a while through a plug top with 6mm bolt as a fuse lol.
The actual pins of the plug welded themselves to the socket such was the arcing due to a poor connection for the current involved.

And with arcing, comes a fire risk.

 

http://www.ebay.co.uk/itm/NEILESEN-5...92461791589456

This is the 1 I might chance

Sounds like I better get the fatherin law and bro in law to check this out for me. (sparkies)

Cheers again steve

 

Can do no harm to price a rewind or similar motor. Or maybe Clarke will sell them too ?

At least new, yes you know exactly what you have.

If you think you're electrical supply is up to handling the 4HP motor, then replace like for like.

But as already mentioned, unless you are sure you have a substantial power supply available, I wouldnt do it on single phase.