I am looking for a  3 phase 100 amp Normally Close mechanical contactor as a fail safe brake for a water turbine. I am trying to find a 3 phase mechanical contactor with the main contacts normally closed. I use that as the final safety brake to connect the PM generator with a resistor bank to prevent the turbine going over speed. All the motor mechanical contactors I seen are Normally Open, and I have a hard time finding a contactor that is 3 phase 460 volt and can handle 100A. Anyone have seen that some where?