Davey ISOSPEC CM Series ISO2858 Heavy Duty Industrial Centrifugal Pump - Manual (Page 3)

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Electrical Connection
Ensure all electrical connections are solid and
continuous. Check motor starter and overloads for
correct rating and trip setting. All circuit breakers, HRC
fuses or protective devices associated with the motor
must be rated to suit motor running current and starting
characteristics.
Starting
Caution: Do not attempt to run pump if it
has not been filled with water (primed).
Severe damage will result to shaft seal.
1) Ensure the suction line & pump casing is full of water
open suction valve if fitted.
2) Check power is off & rotate the pump shaft slowly to
release any trapped air within the pump casing.
3) Close the discharge valve.
4) Check the direction of rotation on the pump casing or
motor cover.
5) Prior to initial start up, the following steps must be
taken:
• Insulation resistance test. On machines up to 600
volt, the minimum value should be 1MΩ.
• Thermistors if fitted, should be checked for continuity
with a multimeter and never mega-tested.
• Ensure supply voltage and frequency correspond to
the motor nameplate ratings.
• Ensure shaft turns freely before initial start.
• Measure stator resistance and record in Log Book.
6) If this is correct you may now start the pump, when
it reaches full speed you will see the pressure in the
discharge line rise. Slowly open the discharge valve
until the pump adjusts to maintain its duty point.
Structural Representation
1. Pump casing 2. Impeller
3. Rear casing cover 4. Stub shaft
5. Bell housing 6. Motor
7. Bolt 8. Bolt
9. Bolt 10. O-ring
11. Bronze wear ring 12. Mechanical shaft seal
13. Impeller washer 14. Impeller nut
15. Impeller key 16. Muff coupling
17. Volute drain plug
Trouble Shooting
Pump is running but failing to deliver water or
desired pressure.
1) Turn the unit off.
2) Check suction line is free of debris or blockages
& check that the pump has not lost its prime. If
so, remove blockage & repeat Starting at step 1).
3) Check that the suction valve is open.
4) Check that the discharge valve is open.
5) Check for air leaks. These may not always be
visible to the naked eye unless pressure is applied
to the suction line.
6) Check that the suction line is not too long.
7) Is suction line to pump excessive?
8) Is the foot valve stuck open or undersized?
9) Is speed too slow?
10) Check motor direction rotation.
11) Check for possible clogging in impeller vanes
12) Is the discharge piping undersized for
applications.
Excessive Vibration
1)
Turn the unit off.
2) Check the motor is rotating in correct direction.
3) Check both motor feet & pump feet are secured
properly.
4) Check drive coupling is secured tightly to the
motor shaft.
5) Check motor bearings are OK.
6) Impeller could be partially blocked causing
imbalance.
Noisy Operation
1)
Turn the unit off.
2) Check motor bearings.
3) Check pump is primed.
4) Check suction line is not damaged, causing
insufficient supply & resulting in cavitation.
5) Check you are not pumping solids.
High Power Consumption
1) Check direction of rotation.
2) Check operating speed on the motor matches the
intended performance curve speed.
3) Check that the estimated head is correct, as pump
may be running down on its curve, producing high
flow, but drawing more power. Throttle the pump
back on to its curve via discharge gate valve or
reduce impeller diameter.
4) The Specific Gravity or Density of the liquid is
greater than 1kg/litre affecting power draw.
5) Check impeller diameter for the correct size, to
establish maximum power requirement at duty
point.
Lubrication
Motor bearings are lubricated with lithium based rolling
contact bearing grease, suitable for operation with-in
the cooling air temperature range of -20 o C to +55 o C.
For operation outside this temperature range, special
lubricants are required.
Special lubricants or additional maintenance may be
required in the case of motors exposed to comparatively
high degrees of pollution, high humidity, increased
or changed bearing loads, or prolonged continuous
operation.
WARNING: When installing, servicing or
attending pump, always ensure power is
switched off and lead unplugged. Electrical
connections should be serviced only by
qualified persons. If the electrical supply lead
is damaged, it must be replaced.