22.5 kw Motor Not Able to Start From a 60kva DG

Does the DG trip out on overcurrent, then? If so, then one possible solution is to inroduce a soft-start unit in the motor starter. Another is to install a programmable variable speed drive unit and program it to run-up to speed more slowly than were the pump to go direct-on-line.

Check Block loading character curve of you Generator first,You haven't mentioned what would be the base load on your generator when it comes on line ,check once again it looks like your generator is undersized.

crm

GA for a good answer in my book....

Because starting current of your motor is more than your generator rated output current. In your case star delta starter will not work it out. as per mr.pwslack metioned select softstarter or VFD or autotransformer.

I don't believe a submersible pump has a delivery line control valve, does it?

Dear Maths,Physics, Maniac,

For submersible pumps valve may not be there, but the question here was related to the MOTOR HP and GENERATOR CAPACITY. The EXAMPLE WHAT I HAVE MENTIONED AND COME ACROSS is 30 H.P. Motor and 60 kVA Diesel Generator Set.

If the submersible pump is of 3 Hp or 5 HP, we do not need a valve in the delivery line when the DIESEL GENERATOR is of 60 kVA. If the motor is of 30 HP and DG Set is of 60 kVA, definitely valve is required in the delivery line, and close before starting, and this will help and solve this particular problem.

I hope the matter is clear to you now.

DHAYANANDHAN.S,

CR4 MEMBER, INDIA.

please let me know

if the dG is tripping ?

What typr of Starter you are using Star Delta type of DOL ?

If DG is tripping that means your stsrting load is very high. If DG is not tripping and motor is working but not delivering the water means there is no enough torque.

So check Frequency and Voltage of Generator it shoud be as given in name plate of 30 Hp motor.

As usual the person who needs to (seemingly) fix/find the problem, has not a clue about:-

a) Electric motors and their starting currents/starters....

b) DG sets in general

c) How to supply the limited amount of data needed to allow an intelligent and helpful reply......

I work for a soft starter company called Aucom Electronics www.aucom.com

As many have indicated, your problem is because the 22.5kW pump can need 6 times or more current than it would normally need when running to start DOL or Direct on Line with a contactor. This is termed a starting current of 6 X FLC ( Full Load Current ). As current is directly related to power ( Power = Voltage X Current ), this means that a DOL start would need a minimum of 22.5 X 6 = 135 kW generator, which you haven't got.

If you can supply me the details of the pump I can determine for you if a soft starter will be able to start your pump with a starting current limit of about 2.5 X FLC. This will demand about 22.5 X 2.5 = 56.25 kW from your 60kVA generator which should be fine.

Good Luck.