Which compressor - grateful for advice

[Chef40]

I have one of those SGS 90L belt drive compressors. I run it though a standard 3 pin plug. It has only tripped the breaker once, I had too many other things on the go when I switched it on.
The compressor seems OK, enough air for my needs.
I'm not doubting your ability at all, did you fill it with oil when it arrived?

Hi Rupert, thanks for your note - I don’t really understand it. I did put oil in it. It’s not the breaker it’s tripping - that could be easy to solve but it’s the actual plug fuse. Maybe I just got a Friday machine - the pump wasn’t bolted on securely either.

 

[Miranda]

Circuit loading for continuous current draw is not as straightforward as it seems. You should not be running breakers anywhere near their max, nor should the theoretical conductor limits be approached...... conductor sizing is not simple.

I would wire a separate 16A blue socket or even a 32A for any future requirements with its own dedicated (properly sized) feed from the incoming supply .....also avoid extension leads on this type of supply like the plague. . things get very very hot very very quickly when run on undersized wiring and sockets..... I have the TeeShirt!!!

 

[Chef40]

Circuit loading for continuous current draw is not as straightforward as it seems. You should not be running breakers anywhere near their max, nor should the theoretical conductor limits be approached...... conductor sizing is not simple.

I would wire a separate 16A blue socket or even a 32A for any future requirements with its own dedicated (properly sized) feed from the incoming supply .....also avoid extension leads on this type of supply like the plague. . things get very very hot very very quickly when run on undersized wiring and sockets..... I have the TeeShirt!!!

Thanks Miranda, I decided to buy one that comes with a 13A plug! :-)
If, in 5 years I’m using it for everything and love it, I’ll think again but I hope what I’ve bought does what I need without more faff!
Sorry to hear you may have found out the hard way :-(

 

[Miranda]

Keep an eye on the plug even then. 13A plugs and sockets do not like 13A continuous, partic if the conductors get a bit corroded or dirty and the resistance goes up.

 

[cheb]

My habit to try and prevent corrosion was to uplug and replug the appliance in every week or so. I used to run an immersion heater for my bio plant via a three pin plug, after the second one welding itself in I started maintaining it.

 

[vw1]

You really needed to start with the free air delivery (FAD) you require, not the supply limits.

That 14cfm quoted is air displacement - somethingbentirely different to FAD, but is

Meaning you won't get 14cfm on whatever your using?

 

[Chef40]

Meaning you won't get 14cfm on whatever your using?

Thanks - I realise... the lower end machines don’t even tell you FAD - I expect when they say 14 it’s more like 9 but that should still power many tools!

 

[Chef40]

Keep an eye on the plug even then. 13A plugs and sockets do not like 13A continuous, partic if the conductors get a bit corroded or dirty and the resistance goes up.

Thanks. If it’s 2200W, in theory it only draws about 9A but it’s when the motor starts that it really pulls

 

[not done it yet]

You really should be starting with the free air delivery (FAD) required, not the leccy supply required.

That 14 CFM is air displacement which is entirely different to FAD. Just a good marketing ploy to befuddle the unknowing. The size of the receiver is only relevant if the compressor is under-sized and air is only used in short bursts.

You can’t really beat a two stage cast iron pump, IMO. Belt driven because the motor can be changed if there is a problem in the future (the non-return valve on my compressor failed, it tried to start on load and the motor failed - it was quite an old machine).

Personally I don't rate the machinemart stuff too highly, but don’t let that put you off.

It is mainly the starting current that is the problem with a 3 HP motor, not the running current - unless the motor runs at low efficiency. Many cheap motors are not very efficient.

 

[marlinspike]

I've often looked at the SGS compressors as they seem very good value, certainly the ones that claim 14cfm are pretty much the cheapest you can get for that amount of air power. I had assumed they were rebadged branded ones as the design is so similar to others. Shame yours proved so poor, and it's always hassle returning big items.

 

[Chef40]

I've often looked at the SGS compressors as they seem very good value, certainly the ones that claim 14cfm are pretty much the cheapest you can get for that amount of air power. I had assumed they were rebadged branded ones as the design is so similar to others. Shame yours proved so poor, and it's always hassle returning big items.

That’s exactly what I did - I realise the 14cfm is a fallacy but it should do at least 8.5 FAD with that displacement.
The value seemed great and as you say, they all look the same.
I now know the likes of Clarke assemble in the UK (even if parts are not) but SGS is entirely Chinese, made ‘to British Standards’.
I’m sure you can get a good one and it’s a bargain but TBH the customer service is poor, returns so far already tricky and my product rubbish in my case - just not worth the risk.
Maybe just spend a few more ££ in the first place and save a headache!

 

[Miranda]

I looked at 100l SGS belt drive as well, probably would have bought it except it has been out of stock for months on end.

I plumped for a factory reconditioned Hyundai 150l, 10bar, 14cfm ... not sure about the FAD figure. Yet to fire it up, appearance wise though like new with the exception of a few minor marks on the tank.