An RS 485 Repeater is a device that amplifies data signals on LAN cables and connects bus segments. It is used in situations where there are more than 32 stations connected to the bus, electrically isolated bus segments are required, or the maximum cable length of a segment exceeds the standard LAN cable length.
This manual describes the RS 485 Repeater used in PROFIBUS networks, its application scenarios, and the rules for installing repeaters to extend bus segments or isolate electrically. It explains when a repeater is required, such as more than 32 stations, isolated segments, or exceeding cable length limits.
Technical data, pinout details, configuration options, and step‑by‑step installation and removal procedures for S7‑300 and standard rails are included. The document also covers ungrounded operation, power‑supply wiring, and LAN‑cable connection guidelines.
| Power supply – Rated voltage | 24 V DC |
|---|---|
| Power supply voltage range | 18 V to 30 V DC |
| Electrical isolation | yes, 500 V AC |
| Redundant mode | no |
| Transmission rate | 9.6 Kbps to 12 Mbps |
| Degree of protection | IP20 |
| Weight (including packing) | 350 g |
A maximum of 9 RS‑485 repeaters can be connected in series.
The maximum cable length is 2000 m.
Tighten the securing screw to a torque of 80 to 110 Ncm.