Service Alarm; Dry-Running Protection - Grundfos CU 301 Notice D'installation Et De Fonctionnement

4.6 Service alarm

If one or more factory-set alarm values are
exceeded, the indicator light for service alarm is
permanently on. See fig. 15.
Fig. 15
Possible alarms
• Sensor defective
• Overload
• Overtemperature
• Speed reduction
• Voltage alarm
• No contact to pump.
The possible alarms and how to identify them and
make the relevant corrections are described in
section
7.1 Fault finding with Grundfos GO
bar
5.0
4.5
4.0
3.5
3.0
2.5
2.0
Remote.

4.7 Dry-running protection

The purpose of the dry-running protection is to
protect the pump in case of insufficient water flow.
The dry-running protection makes the conventional
dry-running protection unnecessary.
No additional cables to the motor are required.
The dry-running protection is active after 30 seconds
of operation.
The dry-running alarm is activated when the load has
been below the minimum power limit for an
accumulated time of 5 seconds.
The motor stops and the dry-running indicator light is
permanently on. See fig. 16, pos. A.
bar
5.0
4.5
4.0
3.5
3.0
2.5
2.0
Fig. 16
Possible cause
The pump performance
is too high compared to
the borehole yield.
The borehole filter is
blocked.
Restarting
After 5 minutes (factory setting), or the period set in
Grundfos GO Remote, see section
restarting, the motor restarts automatically.
A
Remedy
Replace the pump with
a smaller one.
Reduce the pump
performance using
Grundfos GO Remote.
See section
5.3.8 Maximum speed.
Borehole service is
required.
5.3.5 Automatic
13