An energy saver switch is installed in a standard electrical back box by a qualified electrician, where it receives the main power supply and controls the room's electrical outlets. When a specific key card is inserted, it completes the circuit to provide power; when the card is removed, the switch automatically cuts power to the room after a delay to save energy.  

• Standard box:

  The switch is designed to fit into a standard 35mm or 86x86mm single gang electrical back box. 

   

   
• Power connection:

  The main live (L) and neutral (N) wires from the main power supply are connected to the input terminals on the switch. 

   

   
• Circuit control:

  The "load" or "output" terminals on the switch are then connected to the room's circuits, such as the outlets and lighting. The specific wiring diagram will depend on the switch model, and often includes a warning to use a contactor for high-current loads like air conditioning. 

   
• Card reader:

  The card slot is typically located on the front of the switch. 

   
• Delay function:

  The switch contains an internal delay, often 10-20 seconds, that allows the user time to leave the room before the power is cut after the card is removed. 

   
• Indicator light:

  A blue LED on the front of the switch typically indicates when the switch is inactive or when the power is on. 

   

• Card out:

  When the card is removed, the switch's internal relay deactivates after a preset delay, cutting off power to the room. 

   

   
• Energy savings:

  This process ensures that lights and other appliances are turned off automatically when the room is unoccupied, saving energy and money.