The timers have 1/16 din,elecromechenism and time dlay relay system. These timers are integral part of any industry or home having pools. They automatically set the time.
Inground pool timers have many different features. Some of these are multiple on/off operations per day, memory backup features and override functions for pool servicing.
Most inground pool timers have a switch for timing the filtering of the pool water. They can be set to turn on and off at different intervals depending on need.