Siemens Simatic Net Scalance M812 Operating Instructions Manual page 46

Connecting up
4.4 Digital input/output
DI+
DI- (input ground)
If there is an adequate switching voltage at the digital input, the digital input is active and the
"DI" LED is lit.
Digital output
The 2-pin terminal block has the following assignment:
DO+
DO-
46
24 VDC
-
Relay 24 VDC / 1 A
Relay 24 VDC / 1 A
Operating Instructions, 08/2016, C79000-G8976-C343-04
SCALANCE M812, M816