EP1809-0042
Pin  | Function  | Wire color 1)  | 
|---|---|---|
1  | US  | brown  | 
2  | Input B  | white  | 
3  | GNDS  | blue  | 
4  | Input A  | black  | 
5  | FE (Functional earth)  | gray  | 
1) The core colors apply to M12 cables from Beckhoff: ZK2000-5xxx, ZK2000-6xxx, ZK2000-7xxx
Connection examples
Status LEDs
Each M12 socket has two green LEDs. An LED lights up when a high level is detected at the respective input.