Ebara EVM 32 7-3F5/15 [11/107] Troubleshooting

Ebara EVM 3 4N5/0,55 [11/107] Troubleshooting
11
plate. (This approximation is mainly attributable to toleranc-
es and to possible suction lift). If the pressure gauge reading
is much lower than Hmax, repeat lling (air in pump).
If the two values are close, it means the pump is working
properly and any trouble with the isolating valve open is al-
most always a result of motor system problems of an electri-
cal or mechanical nature or, much more commonly, of pump
cavitation due to:
- excessive difference in height or excessive pressure loss
along suction line,
- delivery line backpressure too low;
- problems associated with liquid temperature.
For more information on the factors that reduce and/or com-
promise suction lift and hence the pump’s performance, see
the troubleshooting section in chap. 10.
Also read the instructions given in PART 1 of the manual,
in chap. 9.
With reference to the warnings in point 9.1 a), note that for
temperatures and altitudes higher than those speci ed, the
motor’s output is reduced and you will need to have a motor
with greater output. See chap. 12.1 on the subject.
Make sure there is no water hammer or pressure peaks
in the system caused by fast-closing valves exceeding 1.5
times the pump’s nominal pressure. In the long run, they can
cause damage to the actual pump.
Avoid operating the pump with the isolating valve on the de-
livery line closed for any more than a few seconds.
You should also avoid using the pump for continuous duty
with a ow rate below the minimum rate indicated on the
rating plate as this may result in the liquid being pumped
overheating and in the unnecessary overloading of pump or
motor bearings.
9. MAINTENANCE AND REPAIR
BEFORE COMMENCING ANY MAINTENANCE
WORK ON THE MOTOR-DRIVEN PUMP, TURN
OFF THE POWER
Maintenance and/or repair work must be carried out by
quali ed technical personnel only.
If you need to drain the pump, make sure that the liquid dis-
charged does not cause injury or damage property and that
it does not pollute the environment.
The pump does not need routine maintenance. Perform just
the periodic checks, as recommended in sect. 10 in part 1
of the manual - frequency of said checks will depend on the
liquid pumped and on operating conditions. Said checks
may give you a rough idea of what preventive repairs are
required, if any, instead of having to perform repairs follow-
ing sudden problems.
The repair work most commonly required on EVM motor-
driven pumps consists in replacing the mechanical seal and
motor bearings. Nonetheless, even these parts typically sub-
ject to wear may last a very long time if the pump is used
correctly.
WHEN PERFORMING REPAIR WORK, ORDER
ORIGINAL SPARE PARTS FROM OUR SALES
AND CUSTOMER SUPPORT NETWORK.
NON-ORIGINAL SPARE PARTS MAY DAMAGE
THE PUMP AND BE DANGEROUS FOR PEOPLE
AND PROPERTY.
10. TROUBLESHOOTING
Also see sect. 10.1 in PART 1.
TROUBLE
ENCOUNTERED
CAUSE REMEDY
PUMP NOT
WORKING
Motor fails to
rotate
No electricity
Contact electricity board to
restore power
Circuit breaker
tripped or
fuses blown
Reset circuit
breaker or
replace fuses.
If you en-
counter the
same trouble
again, call
our Servicing
Department
Built-in ther-
mal overload
protection
device (if
tted) or
thermal cutout
in control
panel tripped
(FIG. 3)
Wait for built-
in thermal
overload pro-
tection device
to reset or
reset thermal
cutout in con-
trol panel
Device protec-
ting against
dry running
tripped
Check water
level and/or
correct
connection
of system
devices
PUMP NOT
WORKING
Motor rotates
Pump has not
been lled
Fill (sect. 7)
Caution:
mechanical
seal could be
damaged
Water level
low (if no pro-
tection system
is tted)
Restore water
level
Foot valve
jammed or
lter clogged
Release or
clean
PUMP STOPS
AFTER
RUNNING FOR
SHORT TIME
as a result of
thermal
overload
protection
tripping
Supply voltage
outside mo-
tor’s accepted
range
Check whether there are
excessive drops in voltage due
to undersized line or cables
Inadequate
thermal cutout
setting
Adjust setting to motor’s rated
current (see rating plate)
Motor over-
load due to
dense and/or
viscous liquid
Reduce ow
rate, throttling
the delivery
line or replace
motor with
more powerful
one
Check actual
power absor-
bed 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 impel-
ler rotation
Disassemble
and clean
pump
Call our nea-
rest Servicing
Department
to do the job
Motor bearin-
gs worn
Replace bea-
rings
In this case,
motor is noisy,
too
GB
libretto_EBARA_313_nuovo.indd 11libretto_EBARA_313_nuovo.indd 11 6-02-2009 9:30:376-02-2009 9:30:37

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