5Kv motor reconnected

[Feg]

A customer of mine has had a motor failure on compressor, the original motor was a SIEMENS ODP IP23 500Kw 4pl B5 flanged Model 1LL3352-4HF31-Z 3.3Kv. Due to lack of funds the company is now considering the surplus motor market, one such supplier has offered a second hand MOTOR 1LL3352-4AA51Z 450kw 5000v 65Amp .84 cos 50hz KL4 40 deg max 105K SF 1.1 but reconnected. I have no experience of high tension motors but i am assuming they are talking about reconnecting the motor in delta.Can anyone confirm my thinking and will this work as i thought the voltage tolerance would be only 5 to 10 %, would they be able to use this at 3300v and what kw could be drawn from it. Any comments would be welcome on this subject.

 

[edison123]

A 5000 V Wye connected original winding, when reconnected in delta, would be rated for 2885 V. At 3.3 KV, the voltage rating goes up by nearly 15%. Which would mean iron saturation, higher core temp and definitely much higher no-load current.

Can you post the cost nos. for rewind vs an used motor ? And what is the warranty on the used motor ?

 

[Feg]

Thanks Edison123,

I am not directly involved with this company so don't know the costs, I look after there smaller plant. The old motor is still in place, why do you ask do you rewind ? What part of the world are you in ? The company selling the motor have not offered a warranty yet but they were talking of using at 3000V, but these guys have 3300V. In the past they had a policy of changing out the motor for new but things have changed, the engineers on site got prices in the past and the rewinds nearly always were 1.5 time the new motor price and so they tended to go the new route.

F.E.G

 

[edison123]

Rewinds are 1.5 times a new motor price ????

Man, I am in the wrong part of the world (India).

Send me the motor and I will give you back a better-than- new motor with a 3 year warranty. And it sure wouldn't cost you 1.5 times a new motor price.

 

[Feg]

Yea, rewinder's here are not too common in the high voltage area we are in a small market and they never price the actual job but more like they get the value of the new motor, add a bit on if they know it is urgent and then see what happens.

 

[edison123]

I ran some rough numbers based on motors in that KW and speed range that I have rewound and came up with US $ 15,000 to 18,000 for a full rewind.

How much does a new or an used motor cost ?