EBARA EVM Series - Reduced Flow Rate Issues; Pump Stops (Thermal Overload); Pump Stops (Intermittent Thermal Protection); Pump Fails to Stop (Pressure)

9
EN
DISPLAYED FAULT
CAUSE SOLUTION
THE PUMP WORKS
withareducedow
rate
System
undersized
System
undersized
System dirty
Clean the piping, val-
ves, lters
Water level
too low
Switch off the pump
or immerse the foot
valve
Incorrect rotational
direction
(threephase only)
Invert the two phases
Incorrect supply
voltage
Supply the pump with
the voltage indicated
on the ate
Leaks from piping Check the joints
Pressure too high Recheck the system
PUMP STOPS
AFTER
RUNNING FOR
SHORT TIME
as a result of
thermal
overload
protection tripping
Supply voltage out-
side motor’s accepted
range
Check whether there
are excessive drops in
voltage due to under-
sized line or cables
Inadequate thermal
cutout setting
Adjust setting to
motor’s rated current
(see rating plate)
Motor overload due to
dense and/or viscous
liquid
- Reduce ow rate,
throttling the delivery
line or replace motor
with more powerful
one
- Check actual power
absorbed by the
pump based on liquid
pumped
Pump delivers liquid
at higher rate than
max. ow rate on
rating plate
Reduce ow rate by
throttling delivery line
Panel exposed to
sun or other sources
of heat
Protect panel from
sun or
sources of heat.
Foreign matter brakes
impeller rotation
- Disassemble and
clean pump
- Call our nearest
Servicing De-
partment to do
the job
Motor bearings worn
- Replace bearings
- In this case, motor
is noisy, too
THE PUMP STOPS
AFTER WORKING
FOR BRIEF
PERIODS
Thermal protection
intervention
Liquid temperature
too high
The temperature
exceeds the
technical limits of the
pump
Internal fault
Contact the nearest
retailer
DISPLAYED FAULT
CAUSE SOLUTION
THE PUMP STOPS
AFTER WORKING
FOR BRIEF PERIODS
Pressure
applications
The difference
between
maximum and mi-
nimum pressure is
minimal
Increase the differen-
ce between the two
pressures
THE PUMP DOES
NOT STOP
Pressure applica-
tions
Maximum
pressure too high
Set maximum
pressure at a
lower value
THE PUMP
VIBRATES
Or is too noisy du-
ring operation
Flow rate too high Reduce the ow rate
Cavitation
Contact the nearest
retailer
Irregular piping Fix in a better way
Noisy bearing
Contact the nearest
retailer
Foreign bodies sliding
along the motor fan
Remove the foreign
bodies
Incorrect priming
Bleed the pump and/
or ll it again
When the switch
closes, the pump
does not manage to
complete even one
turn or struggles
to turn the odd half
turn before the cir-
cuit breaker trips or
fuses blow
Motor
short-circuited
Check and replace
Short-circuit due to
incorrect connection
Check and reconnect
correctly
Residual current
circuit breaker trips
as soon as switch
closes
Leakage current owing
to damaged insulation
of motor, cables or
other electric com-
ponents
Check and replace
electric component
with ground fault
Pump performs a
few turns in oppo-
site direction when
stopping
Foot valve leaking Check, clean or replace
Suction pipe leaking Check and repair
Pump vibrates and is
unusually noisy
Motor bearings worn Replace bearings
Foreign matter betwe-
en xed and rotating
parts
- Disassemble and
clean pump
- Call our nearest Ser-
vicing Department to
do the job
Pump operation
affected by cavitation
Reduce ow rate by
throttling delivery line.
If cavitation persists,
check:
- Suction height
- Pressure loss along
suction line (diame-
ter of pipe, elbows
etc.)
- Liquid temperature
- Delivery line
backpressure