Technical specifications   
6.1 GPRS/EDGE router SCALANCE M874-2 
  SCALANCE M874, M876 
64  Operating Instructions, 08/2018, C79000-G8976-C331-08 
Power supply 
Terminal block, 5 terminals 
Properties  Input voltage: 
•  12 to 24 VDC 
•  min. 10.8 VDC, max. 28.8 VDC 
Maximum power consumption 8 W 
Maximum cable length < 3 m 
Digital input 
Terminal block, 2 terminals 
Properties  Rated voltage 24 VDC Safety Extra Low Voltage 
For state "1": 10 to 30 VDC 
For state "0": -30 to 3 VDC 
Maximum input current 8 mA 
Cables should be routed in pairs 
Maximum cable length < 30 m 
Inputs isolated from electronics. 
Digital output 
Terminal block, 2 terminals 
Properties  Rated voltage 24 VDC Safety Extra Low Voltage 
Relay, internally not current limited 
Maximum current carrying capacity 1 A 
Cables should be routed in pairs 
Maximum cable length < 30 m 
Output isolated from electronics 
Permitted ambient conditions 
  During transporta-
-40 ℃ to +70 ℃ 
≤ 95% at 25 °C, no condensation 
Design, dimensions and weight 
Installation options 
•  Wall mounting 
•  Mounting on a DIN rail 
•  Mounting on an S7-300 standard rail 
•  Mounting on an S7-1500 standard rail 
•  Mounting on a pedestal