SQFlex data booklet

CIU 903 SQFlex control unit for remote
monitoring
CIU 903 is a combined monitoring, control and
communication unit designed to work directly with a SQFlex
pump. When combined with a CIM 280 GRM module, it
enables remote monitoring through Grundfos Go. Moreover,
CIU 903 can be connected to a start/stop switch, a level
switch or a pulsating water meter. .
CIU 903 is designed to work with all SQFlex up to 2500 W.
The communication between CIU 903 and the pump is
ensured through the power supply cable. This is called
mains-borne signaling (or power line communication), which
does not require extra cables between CIU 903 and the
pump.
Start, stop and reset the pump with the start/stop switch.
CIU 903 ensures system monitoring and alarm indication.
The pump operation can be monitored through the following
indications:
• water reservoir full (level switch)
• pump running.
CIU 903 indicates the following alarms:
• dry running
• service needed:
- no contact to the pump
- overvoltage
- overtemperature
- overload.
Note: CIU 903 replaces CU 200 in the installation.
81.4 mm (3.2 in)
108 mm (4.25 in)
154 mm (6.1 in)
182 mm (7.2 in)
TM056100
Dimensions, CIU 903
NO
C
NC
External stop Level switch Warning
+
-
1 2 3 4 5 6 7 8 109
TM079822
Electrical connections, CIU 903
24-240VAC 24-240VDC
L N
L N
+ -
TM079823
Electrical connections, CIU 903
SQFlex
4
21
System components