Fault Finding Table - Grundfos MAGNA3 25-80 Installation And Operating Instructions Manual

10.2 Fault finding table

Warning and alarm codes
"Pump communication fault"
(10)
"Alarm"
"Forced pumping" (29)
"Alarm"
"Undervoltage" (40, 75)
"Alarm"
"Blocked pump" (51)
"Alarm"
"High motor temperature" (64)
"Alarm"
"Internal fault" (72 and 155)
"Alarm"
"Overvoltage" (74)
"Alarm"
"Comm. fault, twin-head pump"
(77)
"Warning"
"Internal fault" (84, 85 and 157)
"Warning"
"Internal sensor fault" (88)
"Warning"
"External sensor fault" (93)
"Warning"
Warnings do not activate the alarm relay.
52
Fault
Communication fault between
different parts of the
electronics.
Other pumps or sources force
flow through the pump even if
the pump is stopped and
switched off.
The supply voltage to the
pump is too low.
The pump is blocked.
The temperature in the stator
windings is too high.
• Internal fault in the pump
electronics.
• Irregularities in the voltage
supply can cause alarm 72.
• Overload of the 24 VDC
output can cause alarm 72.
See section Input and
output communication.
The supply voltage to the
pump is too high.
The communication between
pump heads was disturbed or
broken.
Fault in the pump electronics.
The pump is receiving a signal
from the internal sensor which
is outside the normal range.
The pump is receiving a signal
from the external sensor which
is outside the normal range.
Automatic reset
Remedy
and restart
Contact Grundfos Service, or replace the pump.
Yes Check if the pump is running in turbine
operation. See code (29) "Forced pumping".
Switch off the pump on the main switch. If the
light in Grundfos Eye is on, the pump is running
in forced-pumping mode.
Yes Check the system for defective non-return
valves and replace the valves, if necessary.
Check the system for correct position of
non-return valves, etc.
Make sure that the power supply is within the
Yes
specified range.
Dismantle the pump, and remove any foreign
Yes matter or impurities preventing the pump from
rotating.
No Contact Grundfos Service, or replace the pump.
There might be turbine flow in the application
that forces a flow through the pump.
Yes Check if the sensor is blocked by sediments.
This can occur if the media is impure.
Replace the pump, or contact Grundfos Service.
Make sure that the power supply is within the
Yes
specified range.
Make sure that the second pump head is
-
powered on or connected to the power supply.
- Contact Grundfos Service, or replace the pump.
Make sure that the plug and cable are
connected correctly in the sensor. The sensor is
- located on the back of the pump housing.
Replace the sensor, or contact Grundfos
Service.
Does the electrical signal set (0-10 V or 4-20
mA) match the sensor output signal?
If not, change the setting of the analog input, or
replace the sensor with one that matches the
setup.
Check the sensor cable for damage.
Check the cable connection at the pump and at
-
the sensor. Correct the connection, if required.
See section
temperature
The sensor has been removed, but the analog
input has not been disabled.
Replace the sensor, or contact Grundfos
Service.
9.1 Differential-pressure and
sensor.