Block Signalling PPI4-DC Points Position Indicator The Points Position Indicator (PPI) monitors the brief switching voltage to either of the two coils of a points motor, and displays the last operation using coloured leds that can be mounted on a route mimic. Monitors the brief positive operating voltage across points motors when they are switched Lights a corresponding led on a control panel to show the last operation of each set of points Saves all settings automatically to memory when the power is switched off Monitors up to 8 sets of points Adjustable led brightness No resistors are required simplifying wiring Opto-isolated inputs accept voltages from 5V to 25V Requires a 12V DC Power Supply
