KSB CalioTherm Pro 25 Installation & Operating Manual page 29

5 Installation at Site
5.6.1.5 Remote ON/OFF
Fig. 13: RUN terminal pair
R Signal 5 V (+)
0 V GND (-)
ü The wiring diagram is available. (ð Section 10.2, Page 71)
1. Unscrew the cable glands (IPX4D).
2. Wire the external signal (volt-free switching contact) to the RUN terminal pair
integrated in the pump set. The terminal pair is supplied bridged.
3. Tighten the cable glands (IPX4D).
5.6.1.6 Connecting the Modbus system
Connection to higher-level automation systems per Modbus at the example of four
pumps
Communication between the connected pump sets and the Modbus master is
effected via Modbus. Cable reflections occur at the open cable ends (first and last
connection of a bus system). The higher the selected baud rate, the larger the cable
reflections. Provide terminating resistors to establish a defined rest potential and
keep reflections to a minimum.
ü The control unit has been de-energised.
1. Wire the pump sets at their Modbus terminals in line topology as illustrated.
ð Use a network cable with a defined impedance (cable type B to TIA-485-A).
2. Connect a terminating resistor of 120 Ω to the first and last Modbus device of a
bus line.
CalioTherm Pro
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