Digital Dream EC500 User Manual page 12

Picture 5-9 OUTPUT port internal structure
The general output interface has a built-in relay drive circuit, which can be directly connected to less than the
100mA relay. Reference Picture 5-10. for wiring with relay, using output 6(Pin No.2).
COM+
OUT6
Picture 5-10 Solid Replay Connection
Digital Dream Mach3 Motion Controller Page -10 EC500 User's Manual