Servicing The Product - Grundfos CU 301 Mode D'emploi

7. Servicing the product

CU 301 continuously receives operating data from
the pump. In case of an alarm, the service
indicator light is permanently on.
Service alarm indicator
The service indicator light will be permanently on
if one of the following alarm situations occurs:
• Sensor defective
• Overload
• Overtemperature
• Speed reduction
• Voltage alarm
• No contact to pump.
To identify the cause of the service alarm, it is
necessary to remove the front cover from CU 301.
Fit the front cover as shown in fig.
alarm texts on the supply board
disconnecting the ribbon cable.
A number of LEDs are mounted on the supply
board inside CU 301. See section
LEDs.
Figure LEDs and alarm texts on the supply board
shows the LEDs and the alarm texts on the supply
board.
20
PSI
100
90
80
70
60
50
40
LEDs and
to avoid
5.8 Position of
CONTROL INDICATOR
SENSOR DEFECTIVE
OVER TEMPERATURE
SPEED REDUCTION
VOLTAGE ALARM
NO CONTACT TO PUMP
LEDs and alarm texts on the supply board
Related information
5.8 Position of LEDs
MIN. SPEED
MAX. SPEED
OVER LOAD