Timer for Fully-Automatic Star-Delta Oil / Airbrake Starters

we are using fullyautomatic oilimersed stardelta starters and air break starters in that we are using the conventional method of timers to change from star to delta. is there is any other timer avail able than the numatic timers or any other method canbe adopted without using the timer to change from star to delta . mostly our village voltage is from 270-380 v only kindly advise us