Liquid Starter For Mv Motors

[PADENASEMIROM]

hi there!

we have an MV motor for the cement mill separator fan in the factory, voltage of the rotor is 1100v and the nominal rotor current is ... A. and an AKA-EP electrolyte type starter is installed for this motor.

how i can prepare the electrolyte for motor starting?

what should be the resistance of the electrolyte? (ratio of the sodium carbonate and the water?)

how i can measure and adjust the electrolyte resistance?

 

for the first start we had a problem with the current of the rotor which was too high, and causing the relay to cut the power(lock rotor fault), and by emptying the electrolyte and adding distilled water, we reduced the rotor starting current, and thus had the motor started.

after 5 month of work, we found a fault on the motor and after dismounting the rotor we found that there is some damages on the ring of the wound-rotor, caused by electric arc.

now we have repaired the motor and want to start it again, there is a tough investigation that what may have caused this problem to the motor.

1) ratio of the salt and water inside the started tank?

2) from the brushers?

3) from the electrical network?

4) others that you think are possibilities

 

please help me with this situation, as soon as possible,

best regards

padenasemirom

[marke]

Hello padenasemirom

 

Welcome to the forum.

 

The best people to answer your questions, are the manufacturers/suppliers of the starter.

The resistance is a function of the electrolyte, the strength of the electrolyte and the surface area of the electrodes immersed in the electrolyte.

 

Damage to the slip rings is commonly caused by poor maintenance on the brushes and ring gear rather than the starter.

 

Best regards,