Dear JRaef, Thanks for the advice. I plan to use separate starters for each motor. I would like to have advice on selecting the type of starting for my application, the protections required, parameters to be monitored etc. I am in India and service support is also important. Sreenivasan

If you are in India, try any of the following makes:

SIEMENS

L & T

ABB

SCHNEDIER

Siemens in India brand labels the Solcon soft starters

L&T does not seem to offer MV soft starters, only 400V

ABB and Schneider both brand label a MV soft starter made by a company called Motortronics from Florida (USA), but neither of them have good after market support in India, they rely upon Motortronics technicians to fly out from the US. The other people who sell that same Mototronics product in India and have their own local support for it is Elletronica Santerno. I think the product has problems however.

Solcon has a partner sales and support organization in India called Emco-Kimo in Mumbai, plus their product is also brand labeled by Igel GMBH, who also has distributors in India.

You can use 6.6kv auto-trans starters.It will involve autotransformers (oil immersed or cast resin type),6.6Kv Vacuum contactors,analogue or digital controller and protection relays for motor starters.Main 6.6KV switchboard.This is a simpler and trouble free starter when designed by experienced consultant/manufacturing engineers.

It is important to obtain from motor and mechanical system manufacturers,the sufficient starting and running imformation of motors in terms of inrush current,starting current at the mechanical torque needed,type of liquid/gas to be pumped,number of start-stop per hour,tapping percentage of each tapping,number of steps, of autotrans, and kva sizing of autotrans.Many so called "big and advance" electrical company cannot design and built such starters.They will point fingers at others when components starts to burn .Look for those companies who has longer experience and you will be alright.I was involved in many such starters used in water pumping and gas compression projects.

Regards,

Khor.