Source for 3PH motor & Inverter

[RickH]

For a project I am going to need a 8 pole 3ph motor ... to get around 720 rpm (Could make do with 6 pole 950 rpm at a push)

Also an inverter to run it on 1ph, and also private soft start over 5sec or so.

Anybody know any on-line sources for such 2nd hand gear ?

 

[Spark123]

ebay?
How about using a gearbox?

 

[RickH]

I'm in 'mulling it around' mode.

Need to power a soil sifter / sieve .... so need a reasonably low shaft speed (direct or gearbox)
Also need soft start ... so I can load up sieve and then press start.

Advice seem to be a 3/4hp 3ph motor - 6 pole to get lower full load speed, and run this via a 1ph to 3ph inverter.
this would give me the 3ph conversion and soft start.

But open to ideas

 

[Spark123]

Petrol engine with clutch?

 

[ColJack]

concrete mixer with holes cut out and covered with screening mesh..?

alternatively a decent 3 phase inverter will give you speed controll and soft start..

 

[RickH]

agreed ... hence my original Q of where I can pick these up 2nd hand ... tried eBAy.

Need a 3PH motor 3/4hp would be enough (1/2hp may even do it)
plus suitably sized controller.

 

[bhm1712]

i have never seen an inverter drive for sale on ebay etc ever.

another way to do it would be to use a DC motor and dc control circuit? probably alot cheaper to buy the stuff if you cant find the 3phase stuff.

then there is the possibilty of getting a cheap DC motor from an old washing machine etc....unless its a 240v 3 phase washing machine which is becoming more common now (indesit, hotpoint super silent etc)

 

[ColJack]

3/4HP motor, inverter and speed controll on e-bay

 

[bhm1712]

all you would need then was a decent solid state rectifier which are cheap as chips.

 

[bhm1712]

for that lot on ebay id say it was cheap! our ABB inverters alone cost more than the whole package!

 

[ColJack]

what is the minimum output rpm you want?

there's a motor on e-bay with a 100prm output?
one with 67rpm...
240V AC 240prm for a tenner? ( no idea on the torque though.. )

 

[Jaymack]

I'm in 'mulling it around' mode.
Need to power a soil sifter / sieve .... so need a reasonably low shaft speed (direct or gearbox)
Also need soft start ... so I can load up sieve and then press start.
Advice seem to be a 3/4hp 3ph motor - 6 pole to get lower full load speed, and run this via a 1ph to 3ph inverter.
this would give me the 3ph conversion and soft start.
But open to ideas

You should look at the comparative costing of a belt drive, using a single phase motor with soft starter.

Regards

 

[ColJack]

how do you want this sieve to operate?

cam on the end of the motor just bumping the thing up and down?
cam and lever arm to shake it back and forth?
uneven weight on the end to just vibrate it?