KSB CalioTherm Pro 25 Installation & Operating Manual page 33

5 Installation at Site
5.6.1.7 Connecting dual-pump configurations
Wire the two pumps to each other with a suitable network cable (wave impedance
120 Ω), via the terminal pairs DUAL (a5).
Setting
Make sure the settings and wiring of both pumps are identical to ensure that the
changeover from duty pump to stand-by pump will not have any impact on the duty
point and operating mode. Connect the control modules of the two pumps with a
commercial, shielded data cable. The terminals of the RUN terminal pair must be
bridged at both pumps.
Vin
a1
0 V
R
a2
0 V
1
a3
2
D-
a4 D+
0 V
L
a5
H
0 V
Fig. 17: Terminal wiring diagram for dual-pump configuration
a Data line connections
a1 External 0 - 10 V
a2 Remote ON/OFF
a3 Terminating resistor for Modbus cable (DIP switches)
a4 Modbus
a5 Dual-pump configuration
CalioTherm Pro
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