Neptune NSP-M Operating Instructions Manual page 28

Neptune solenoid pump NSP-M
Possible cause
Suction line is blocked (e.g.
screen in foot valve)
Viscosity too high
The dosing pump's electrical
data does not match that of
the mains supply
Suction side pressure too high
(pump siphoning)
Pressure peaks due to
acceleration with long suction
lines
Imprecise dosing due to
changeable positive and
negative suction heads.
System backpressure too
high (measured at discharge
connection of dosing pump)
Table 20: Type of fault: Delivery rate varies
12.1.4 No stroke movement observed
Possible cause
Diaphragm return spring
broken.
Current supply interrupted
The dosing pump's electrical
data does not match that of
the mains supply
Pressure peaks due to
acceleration with long suction
lines
System backpressure too
high (measured at discharge
connection of dosing pump)
Table 21: Type of fault: No stroke movement observed
Troubleshooting
28
Remedy
è
Clean the suction line.
è
Possibly reduce the concentration
of the dosing medium or increase
the temperature.
è
Install spring-loaded valves.
è
Increase the pipe diameter.
è
Check the electrical installation.
è
Install a back-pressure valve in
the pressure line.
è
Install a suction pressure
regulator.
è
Install a suction pressure
regulator.
è
Clean blocked injection nozzle.
è
Install pulsation dampeners to
reduce pressure peaks if pipes
are too long.
è
Check the safety valves.
Remedy
è
Contact the manufacturer.
è
Reconnect the current supply
è Check the electrical installation.
è
Install a suction pressure
regulator.
è
Clean blocked injection nozzle.
è
Install pulsation dampeners to
reduce pressure peaks if pipes
are too long.
è
Check function of safety valves.
12.1.5 Dosing pump delivery rate too high
Possible cause
Suction side pressure too high
(pump siphoning)
Pressure peaks due to
acceleration with long suction
lines
Table 22: Type of fault: Dosing pump delivery rate too high
12.1.6 Diaphragm is torn or tears too often
Possible cause
Shut-off valves closed
Pressure peaks due to
acceleration with long suction
lines
The materials are not suitable
for the dosing medium being
used
Diaphragm not screwed up to
the end stop on the dia-
phragm rod
System backpressure too
high (measured at discharge
connection of dosing pump)
Media sediment in dosing
head
Table 23: Type of fault: Diaphragm is torn or tears too often
12.1.7 Loud noises on the dosing pump
Possible cause
The drive magnet's stop
damper is worn-out
Table 24: Type of fault: Loud noises on the dosing pump
Operating instructions
Remedy
è
Install a back-pressure valve in
the pressure line.
è Install a suction pressure
regulator.
Remedy
è
Open the shut-off valves. Inspect
the dosing pump for possible
damage.
è
Install a suction pressure
regulator.
è
Check the resistance of the
materials.
è
Screw a new diaphragm up to the
end stop.
è
Clean blocked injection nozzle.
è
Install pulsation dampeners to
reduce pressure peaks if pipes
are too long.
è
Check function of safety valves.
è
Clean the dosing head.
Remedy
è
Contact the manufacturer.