The RB1 Intercall Relay Board converts the O/C output from the LCD Displays and L746 Over Door Light into ‘normally open’ and ‘normally closed’ contact sets. The unit may also be configured by the factory to provide time delays for some door applications. It may be used to trigger a Call Point from an external voltage (e.g. Door Bell etc.). The unit is fitted with a ‘T’ 12v output which may be used to drive low current devices from the network.