Author Topic: Another IMAG attempt.  (Read 221 times)

glort

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Another IMAG attempt.
« on: February 03, 2019, 10:25:20 AM »

Went and picked up another induction motor this afternoon.

When I saw them the other week I was certain I saw they were 30 Kw. Unfortunately I must have been getting overcome with wishful thinking.  Reality today says they were only 12's so I just brought one home. Can't even see a figure of 30 on them now so not sure where I got that from.

Funny thing is, I have been looking for something this size for a while and was thinking a 30 was too big then decided they only do what you drive them to after all .  Now I feel a wee bit dissapointed they aren't 30 kilo monsters but anyway.

Speaking or monsters, the one I got weighs in at a substantial 170 Kg. A 30 Kw Might weigh half a ton.  Might be enough to keep the roid from walking round the the yard!  But I doubt it.

This Motor has a 100 mm Pulley. The rated speed is 1455 RPM which means I'll have to drive it at or above 1600 RPM.
The pulley on my 5.5 Horizontal Diesel is 65mm. The engine is rated to 3000 Rpm which seems a bit quick for one of these and also I couldn't get my last IMAG to come on song because it wasn't turning fast enough so I'm a bit dubious about that speed. Generally these engines are about 24 or 2600Rpm.

To get 1650 RPM on the motor the engine should only need to do a bit over 2500 RPM so I SHOULD be ok and have a bit of margin in any event. That's the first Hurdle out the way.

2nd hurdle is that I have forgotten more about this now than I remember, again and the 3rd thing is this is a 6 pole motor where as the others I have played with have been 3 Poles. I was thinking I just time them together in a delta Config and treat them as a 3 pole from there.

Over the next few days hopefully weather, work and motivation permitting, I might be able to screw it all down on a suitable heavy duty base and fire it all up.

I'd like to try a stand alone generator and also a grid tied. That might be very useful over the winter solar fall off time.


mike90045

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Re: Another IMAG attempt.
« Reply #1 on: February 03, 2019, 11:49:22 PM »
You may have seen a 3 phase symbol:
3
 which might look like 30

glort

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Re: Another IMAG attempt.
« Reply #2 on: February 04, 2019, 01:42:32 AM »

Something I haven't seen before that the smart people may be able to enlighten me on...

On the spec plate,  It says
 KW  12/2.4
Volts  415
Amps 21.3 /6.1
RPM 1455/ 735
Conn 2 star/star

If the motor was say 240/ 415 it would explain to me why the 2 differnt ratings but what is the purpose and setup of a motor that does 12 or 2.4 Kw and what the heck is 2 star?

My guess for the double rating on the motor is a lower power, higher start torque like a single phase motor start windings. The lower output would be wired with a timer but... I was of the thought that would be a star start, Delta run configuration.  Not sure how you would do a star/ star?

Even though the motor is specced as star with the 2 lots of 3 terminals, I don't see what is stopping a delta config.
Is one going to be better than the other for stand alone and another for gried tied?

I also see a couple of light wires coming out into the box that are just loose with a couple of screw terminals. Look like they are too light to carry any current. Could these be for an indicator light of some sort/ speed sense  or temp sense?

Probably won't get to do much today other than unload the thing as I have had a quick shoot come up this afternoon so see how I go tomorrow.

mike90045

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Re: Another IMAG attempt.
« Reply #3 on: February 04, 2019, 03:45:05 AM »
It could be an energy saver motor, with 2 sets of windings, for idle and full load ??

oldgoat

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Re: Another IMAG attempt.
« Reply #4 on: February 04, 2019, 10:24:12 AM »
Could also be a 2 speed motor. speed is changed by pole switching if I remember correctly look up dahlander connection.

saba

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Re: Another IMAG attempt.
« Reply #5 on: February 04, 2019, 10:26:40 AM »
Hey Glort it's a dahlander motor, I use it for my chp start the lister with the low rev setting when the lister is reaching it's 600 revs I kick in the high revs to feed back. It's from the days when the frequency drives were still expensive. Now they still use it to drive big fans for example.

gr Bernhard

glort

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Re: Another IMAG attempt.
« Reply #6 on: February 04, 2019, 02:49:05 PM »

Did some research and found the product data sheet and it is indeed a 2 speed motor. It did come off a big fan for a Chiller unit.
They were upgraded with newer, more efficent motors about 10 years ago and have been in storage ever since.

What I can find so far says that one set of 3 terminals is low speed winding and the other high and you can't bridge them together like the normal 6 terminal motors.  Anyone know if this is correct?

The 2 Speed thing could be very  handy for starting an engine.  With less than 6A per phase, very doable. I have 2 phases going to the shed so could wire 2 Up and throw a cap on the other leg for starting purposes.

Got the thing unloaded today, what a beast.  Frame is going to have to go on wheels or it will be impossible to move.

Next Question is mounting. I was thinking I'd need some C channel  So I can either bolt in directly or cross pieces but then thought some Square tube should be ok. To bolt in direct can just cut some holes where the bolts go with the plasma for access.  For the engine I picked up a lot of  uni strut a while back and could weld that to the sq tube for belt adjustment.

Going to be a substantial Piece when it's done that's for sure!