Goulds Pumps 3500XD - IOM User Manual
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3500XD IOM 8/07
Table 3
TROUBLESHOOTING THE MODEL 3500XD STANDPIPE INSTALLATION
PROBLEM
SYMPTOMS
POSSIBLE CAUSE
SOLUTIONS
Pump will not start pumping
Amps to drive motor normal
Control valve LCV does not
open
Check that the supply air
pressure to the actuator is
sufficient
Discharge pipe plugged
Open by flushing, check
that any manual valves in
the discharge pipe are open
Amps to drive motor below
normal
ARV has not opened
Open manually and check
setting on LCV limit switch
Pressure in air removal
piping too high
Check that the vacuum
pump is running and the
setting of the vacuum relief
valve
Air removal pipe plugged
with stock
Flush air removal piping
Pump discharge flow too low
Level control valve 100%
open
Standpipe dilution valve not
operating, or dilution water`
pressure too low
Check that dilution valve is
operating, check dilution
water pressure
Flow too high compared to
pump capacity
Check pump and motor
speed, check V belts if V
belt driven
Pump power consumption
and air removal pressure
unstable
Level in standpipe too low,
or air removal pressure too
high
Raise the level set point in
the standpipe, or reduce
pressure in air removal
piping
Stock discharge pipe vibrates
Power consumption and air
removal pipe pressure stable
Discharge piping
inadequately supported
Improve discharge pipe
supports and anchors
Power consumption and air
removal vacuum unstable
Stock in the standpipe has
large voids, or the
consistency is too high
Make sure that stock
delivered to the standpipe is
well shredded. Dilute if
necessary by adding
dilution at the shredder
screw and to the upper part
of standpipe.
The signal to the level
control valve is unstable
Check the valve movement,
delay the input from the
level transmitter if
necessary
Level measurement is too
sensitive
Add filtering, or delay the
input to the LIC
Motor overloaded
Motor overloaded
Volume flow above normal
Consistency is too low,
switch to manual control
Flow unstable
Power consumption normal
Flow transmitter is too
sensitive
Increase transmitter
response time
Power consumption normal
but changes with the level
control valve opening
Control not working
properly
Recalibrate or adjust
controller