
SCALANCE M874, M876
Operating Instructions, 08/2018, C79000-G8976-C331-08 7
Preface ................................................................................................................................................... 3
1 Security recommendations...................................................................................................................... 9
2 Description of the device....................................................................................................................... 15
2.1 Product characteristics............................................................................................................15
2.2 Accessories.............................................................................................................................17
2.3 Terminals ................................................................................................................................20
2.4 LED display.............................................................................................................................22
2.4.1 SCALANCE M874-2, M874-3 .................................................................................................22
2.4.2 SCALANCE M876-3, M876-4 .................................................................................................26
2.5 SET button ..............................................................................................................................28
2.6 C-PLUG and KEY-PLUG ........................................................................................................30
3 Installation ............................................................................................................................................ 31
3.1 Securing the housing ..............................................................................................................32
3.2 Wall mounting .........................................................................................................................34
3.3 Installation on the DIN rail.......................................................................................................36
3.4 Installing on the S7-300 standard rail .....................................................................................38
3.5 Installing on the S7-1500 standard rail ...................................................................................39
3.6 Installation on a desktop pedestal ..........................................................................................41
4 Connecting up....................................................................................................................................... 43
4.1 Safety when connecting up.....................................................................................................43
4.2 SIM card..................................................................................................................................45
4.3 Power supply ..........................................................................................................................46
4.4 Grounding ...............................................................................................................................48
4.5 Digital input/output ..................................................................................................................49
4.6 Antennas.................................................................................................................................52
4.7 Ethernet port ...........................................................................................................................55
4.8 Inserting and removing the PLUG ..........................................................................................56
5 Dimension drawings.............................................................................................................................. 59
5.1 SCALANCE M874-2, M874-3 .................................................................................................59
5.2 SCALANCE M876-3, M876-4 .................................................................................................61