The pumping system which is the heart of the installation consists of specialized pumps (of approved design) which are fully automated to ensure that water is available throughout the system under the recommended pressure at all times.  Mere opening of a single hydrant landing valve outlet will make water available to fight the fire without having to run to the pump house to start the pump.  The resultant drop in pressure in the pipeline automatically triggers a pressure switch which starts the pump. 

However, smaller systems may not be required to be automatic. The connection to the system is taken from two sub-stations with changeover contacts. The Lift, the staircase lighting and the fire fighting pump sets are connected in the above manner so that in the event of fire, if the normal source is destroyed, power will still be available through the change over contact.