Operating instructions
3.
Speed too high
•
reduce speed
•
compare speed of motor with specified pump speed (rating plate)
•
when adjusting speed (frequency transformer) check reference value setting
4.
Speed too low
•
increase speed (check available motor power)
•
compare speed of motor with specified pump speed (rating plate)
•
when adjusting speed (frequency transformer) check reference value settings
5.
Impeller diameter too large
•
use smaller impeller
6.
Impeller diameter too small
•
use larger impeller (check available motor power)
7.
Pump and/or pipes not completely filled with liquid
•
fill
•
vent
8.
Pump or suction/intake pipe blocked
•
clean
9.
Air pocket in pipeline
•
vent
•
improve course of pipe
10.
NPSH of system too small
•
increase liquid level
•
increase admission pressure
•
reduce resistance in the intake/suction pipe (change course and rated width, open shutoff
valves, clean filters)
11.
Air being sucked in
•
increase liquid level
•
check suction pipe is vacuum-tight
•
provide spindles in suction pipe fittings with water seal
12.
Air being sucked in through shaft sealing
•
clean sealing pipe
•
increase sealing pressure
•
replace shaft sealing
13.
Direction of rotation is wrong
•
swap over two phases of power supply (to be done by a specialist electrician)
Pa 100/3-en
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