Topology - Macurco MRS-485 User Instructions

Macurco MRS-485 Modbus RS-485 Adapter
Note: It is recommended to always use twisted wires to reduce noise and allow for reliable data communication
over greater distances. Use at least 3-conductor wire with one twisted pair providing a pair for signal (A & B) and
Common (COM) connections.
For best performance use shielded 3-conductor wire with one twisted pair providing a pair for signal (A & B),
Common (COM) and shield ground (SHD) connections.
3.4.2

Topology

An RS-485-Modbus configuration without repeater has one trunk cable, along which devices are connected,
directly (daisy chaining) or by short derivation cables. The trunk cable, also named "Bus", can be long. Its two
ends must be connected on Line Terminations. (see Line Termination - End of Line Resistor section). The use of
repeaters between several RS-485-Modbus is also possible.
Figure 3-3 Modbus Wiring
REV – 1.0 [34-2900-0019-8] 10 | P a g e