1. The interlock for lubrication pressure and alternating lubricating oil pump, direct lubricating oil pump, jacking oil pump and turning gear of the lubricating oil system.
2. The interlock for feed water pump, condensate pump,  condensate-boosting pump, vacuum pump ,circulating water pump, drainage pump and the other kinds of water pumps and their corresponding systems. 
3. The interlock for the spare pump when the working pump trips by accident.
4. The interlock for all kinds of pumps and their inlet and outlet electric operate valves.