CompAir Autopower VS8

[MonsterLandrover]

Morning all,

I have been given this CompAir Autopower VS8 compressor and I'm going to cba ge it to single phase. The tag in the 3ph motor says its a 3/4hp motor which seems really anemic to me. I have spent a long time on Google but can't find a scrap of information about it. I have contacted CompAir but they don't want to know as its not in their current lineup. To be honest, it's just Ingersoll Rand using the compair name now.

So my question is, do I get a similar rated motor or do I put a higher power one on?

 

[carbon]

Yes does seem to be a 0.55kw motor 80 frame so should be 80mm between the bottom of the foot mounting to the centre of the shaft

see this link for motor details https://inverterdrive.com/group/Motors-AC/ac-Motor-550W-550-Watts-4Pole-4-pole-Foot-Mounting/

 

[MonsterLandrover]

Yes does seem to be a 0.55kw motor 80 frame so should be 80mm between the bottom of the foot mounting to the centre of the shaft

see this link for motor details https://inverterdrive.com/group/Motors-AC/ac-Motor-550W-550-Watts-4Pole-4-pole-Foot-Mounting/

That's the one. Just seems very small for a compressor of this size

 

[carbon]

Is it a single cylinder pump? It does look like there is a 80 frame single phase motor that has a 1 hp output but they don't seem to list a torque value for it like they do for the three phase one.

 

[MonsterLandrover]

Yes it's a single cylinder

 

[carbon]

Ive just had a quick look through the tec catalogue, https://inverterdrive.com/file/TEC-Motor-Technical-Catalogue
The torque value listed for the three phase motor that's fitted is 3.87nm there single phase motor 0.55kw has a torque value of 3.75nm and the 0.75kw motor has a torque value of 5.08nm. If it was me I'd fit the 0.75kw as there only seems to be a few pounds difference in the price. Its possible that a bigger motor may fit without much modification

 

[carbon]

Was it running ok with the three phase motor?

 

[MonsterLandrover]

Not sure to be honest

 

[MonsterLandrover]

Apparently it did. I take it it needs to be a 4pole 1400rpm? I actually have a 2800rmp 2 pole. Would that be too fast?

Sorry for the questions, you lot are a lot more knowledgeable than me

 

[carbon]

I would have thought too fast with a 2 pole motor, as the motor pulley would need to be reduced in size to have the pump run at the correct speed.

 

[MonsterLandrover]

Sorted it, I've bought a VFD for it I know it's chinesium but for £40 delivered I'll give it a go. Cheaper than a motor and I can do some advanced things like soft start and possibly overdriving it if I need a little more flow.