Siemens SIMATIC RF185C Operating Instructions Manual page 25

Reader connector system
A reader always occupies one M12 socket on the RF18xC. You can connect the reader to
the communications module using a preassembled cable. The connection cable is available
in lengths of 2, 5, 10, 20 and 50 m as standard. If necessary, these can be extended.
Figure 5-3
SIMATIC RF185C, RF186C, RF188C
Operating Instructions, 10/2018, C79000-G8976-C512-01
Overview of connections
Connection
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