I/O LEDs

Each CPU contains up to 15 LEDs (depending on type) to display the statuses of the inputs and outputs.

CPU type LED Status Color LED = ON LED = OFF

PM554

PM564

I0 … I7 (PM554)

I0 … I5 (PM564)

Digital input yellow Input is ON Input is OFF
O0 … O5 Digital output yellow Output is ON Output is OFF
PM564 AI0, AI1* Analog input yellow Input is ON Input is OFF
AO Analog output yellow Output is ON Output is OFF

* The analog inputs AI0 and AI1 can be configured as digital input or analog input.