Servicing The Product - Grundfos CU 301 Installation And Operating Instructions Manual

6. 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.
on the supply board to avoid disconnecting the
multicore cable.
A number of LEDs are mounted on the supply board
inside CU 301. See section
Figure LEDs and alarm texts on the supply board
shows the LEDs and the alarm texts on the supply
board.
22
bar
5.0
4.5
4.0
3.5
3.0
2.5
2.0
LEDs and alarm texts
4.8 Position of LEDs.
CONTROL INDICATOR
SENSOR DEFECTIVE
OVERTEMPERATURE
SPEED REDUCTION
VOLTAGE ALARM
NO CONTACT TO PUMP
LEDs and alarm texts on the supply board
Related information
4.8 Position of LEDs
MIN. SPEED
MAX. SPEED
OVER LOAD