Grundfos CU331SP User Manual

English (US)
16
Fig. 23 Position of the pressure sensor and diaphragm tank
Diaphragm tank
The stop function requires a diaphragm tank of a certain minimum
size. The tank must be installed as close as possible after the
pump and the precharge pressure must be 0.7 x actual setpoint.
Recommended diaphragm tank size:
If a diaphragm tank of the above size is installed in the system,
the factory setting of ΔH is the correct setting.
If the tank installed is too small, the pump will start and stop too
often.
13. Maintenance and service
13.1 Cleaning the CU331SP
Keep the cooling fins and fan blades clean to ensure sufficient
cooling of the CU331SP.
13.2 Service parts and service kits
For further information on service parts and service kits, visit
www.grundfos.us > website> WebCAPS.
14. Fault finding
14.1 Warning and alarm list
1)
In case of an alarm, the CU331SP will change the operating
mode depending on the pump type.
2)
Warning is reset in display 3.20.
14.2 Resetting of alarms
In case of fault or malfunction of the CU331SP, check the alarm
list in menu OPERATION. The latest five alarms and latest five
warnings can be found in the log menus.
Contact a Grundfos technician if an alarm occurs repeatedly.
14.2.1 Warning
The CU331SP will continue the operation as long as the warning
is active. The warning remains active until the cause no longer
exists. Some warnings may switch to alarm condition.
14.2.2 Alarm
In case of an alarm, the CU331SP will stop the pump or change
the operating mode depending on the alarm type and pump type.
See 14.1 Warning and alarm list.
Pump operation will be resumed when the cause of the alarm has
been remedied and the alarm has been reset.
The CU331SP has an automatic reset function for all alarms
(except "Locked Alarm" as listed above.) The automatic reset
time is 10 seconds for all alarms except Dry-Run. The Dry-run
alarm will reset after 30 minutes.
TM05 5804 3912
Rated flow rate of pump
[gpm (m
3
/h)]
Typical diaphragm tank size
[gallon (L)]
0-26 (0-6) 2 (7.5)
27-105 (7-24) 4.4 (16.7)
Pressure sensor
Diaphragm tank
Pump with non return valve
Code and display text
Status
Operat-
ing mode
Reset-
ting
Warning Alarm Locked alarm
1
Too high leakage
current
●
Stop Man.
2 Mains phase failure
●
Stop Aut.
3 External fault
●
Stop Man.
16 Other fault
● Stop Aut.
●
Stop Man.
32 Overvoltage
●
-Aut.
●
Stop Aut.
40 Undervoltage
●
-Aut.
●
Stop Aut.
48 Overload
●
Stop Aut.
●
Stop Man.
49 Overload
●
Stop Aut.
55 Overload
●
-Aut.
●
Stop Aut.
57 Dry running
●
Stop Aut.
64
Too high CU331SP
temperature
●
Stop Aut.
89 Sensor 1 outside range
●
1)
Aut.
96
Setpoint signal outside
range
●
1)
Aut.
155 Inrush fault
●
Stop Aut.
241 Motor phase failure
●
-Aut.
●
Stop Aut.

Grundfos CU331SP Specifications

General

Brand	Grundfos
Model	CU331SP
Category	DC Drives
Language	English