Is my compressor 3 phase?

[Trev3635]

Can anyone tell me whether my compressor is single or three phase as i dont do electrics. I bought it at auction and don't wanna plug it in in case i melt the house! It's a clarke 'air' industrial. I also too a couple of pics.



The white box in the middle is a stop start switch and it has wires from the motor. On the left it has blue on the top black in the middle and brown at the bottom.



If it is three phase does anyone know what i would need to do to convert it to single phase domestic so i don't blow up the house?

 

[piman]

Hello TRev,

it does look like it's three phase alright. What is the motor size, (H.P. or KW)?

You either need to source a single phase motor, not sure if anything much larger than 2.2Kw will be available, or else you'll need to buy a single to three phase converter. Most are 240v single to 240 three phase so your motor needs to be a 240\415. There are some 240v single to 415v three phase ones available but they're not cheap.

Alec

 

[brightspark]

look at the plate on the motor if it says dual voltage 230 /415volt its 3 phase . it looks to be the case in the starter brown blue and black .see how many kw the motor is on the plate that wil indicate how many horsepower it is . if its bigger than 4 horsepower u will struggle to run on single phase . 5hp would be max on domestic supply not using anything else on circuit when starting

 

[Trev3635]

Thanks guys.

Spied a motor on flea bay: 0.55 kw (3/4 hp)
2800 rpm
4 amps

Would i be able to fit this? seems reasonable at £49 + £10p&p

Wish i knew more about electrics.

 

[mike os]

Thanks guys.

Spied a motor on flea bay: 0.55 kw (3/4 hp)
2800 rpm
4 amps

Would i be able to fit this? seems reasonable at £49 + £10p&p

Wish i knew more about electrics.

not even close ... 2.5-3hm min I would think

what does the makers plate say... model no?

 

[scarecrow]

looks single to me brown blue and green wires

 

[mike os]

looks single to me brown blue and green wires

and the black?

 

[outofthefire]

Is there a plate on the motor. If there is it should say how powerful it is, you then need a single phase motor with the same power output.

 

[scarecrow]

and the black?

a yes i see it but there only looks to be 3 connector on the in side of the switch

 

[tigler]

Looks like 3 phase to me. Get the info off the motor data plate to see what the options are.

 

[michael1703]

looks single phase judging by the wire gauge

 

[scarecrow]

this is the nearest i can find to it but is 7.5hp

http://uk.ebid.net/for-sale/clarke-air-compressor-400v-wis-30cfm-270-ltr-26515770.htm


thats not the original motor on her so might have been convert all ready hope they changed the pulleys

 

[the snooper]

the switch you show in the picture doesnt look original the first picture shows the original on / off presure switch.
the easiest way to determine if its three phase is the numer of wires to connect to the mains plug.
3 and its single phase
4 and its three phase

 

[mike os]

a yes i see it but there only looks to be 3 connector on the in side of the switch

3 con in the contactor & earth = 3 phase... or at least teh serious suspision of it

 

[mike os]

what does the makers plate say? silver thing in the piuc?

 

[piman]

Hello all,

"what does the makers plate say?". as Mike says, that's what I asked in my first post.

If it is single phase, where's the start capacitor?

Alec

 

[Trev3635]

I have had a look on the motor today and it has a black rating plate on it, which for me is hard to comprehend, however it has 240/440 and 230/420 so i presume this would definately confirm it to be three phase.
Cheers fellas.

 

[mike os]

depending on the motor capacity it will probably be cheaper & better to buy a 3 phase inverter rather than change the motor... and gives you the option of getting other 3p kit rather than having a motor thats of no use to you.

 

[piman]

Hello Trev,

that's not quite right, it does mean that it's three phase but the majority of three phase motors are marked 415 with no mention of 240.

Alec

 

[Trev3635]

How much would an inverter cost me then?