Grundfos VLSE, Инструкция по установке и эксплуатации

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English (US)
6. Operation
6.1 Priming
• The Grundfos Type VLSE in-line centrifugal pumps are not self
priming, and must be completely primed (filled with liquid)
before starting.
• If the pump will operate with a positive suction head, prime by
opening the suction valve and allowing liquid to enter pump
casing.
• Open all air vents a the high points of pump and piping to
ensure air is forced from pump by liquid.
• Disconnect the recirculation line at the seal housing and bleed
completely of all air.
• Re-connect the line prior to start-up.
• Rotate the shaft by hand to free entrapped air from impeller
passageways.
• If pump has a suction lift, priming must be accomplished by
other methods.
• The use of foot valves or ejectors, or manual filling of the
pump casing and suction line with liquid are possible methods
suggested for this purpose.
6.2 Pre-start checklist
Make the following inspections before starting your Grundfos
Type VLSE pump:
1. Make sure all wiring connections to the motor (and starting
device) match the wiring diagram and produce clockwise
rotation as viewed from the end of the motor.
2. If the motor has been in storage for an extended length of
time, either before or after installation, refer to motor
instructions before starting.
3. Check voltage, phase, and line circuit frequency with the
motor data plate.
4. Turn rotating element by hand to make sure it rotates freely.
5. Tighten plugs in gauge and drain taps. If pump is fitted with
pressure gauges, keep gauge cocks closed when not in use.
6. Check suction and discharge piping for leaks, and make sure
all flange bolts are securely tightened.
6.3 Motor rotation
6.4 Starting the pump
1. Install coupling guard on split coupled units.
2. Fully open gate valve (if any) in suction line, and close gate
valve in discharge line.
3. Fill suction line with liquid and completely prime pump.
4. Start the motor (pump).
5. Immediately make a visual check of pump and suction piping
for pressure leaks.
6. Immediately after pump reaches full operating speed, slowly
open the discharge gate valve until complete system flow is
achieved.
7. Check discharge piping for pressure leaks.
8. If pump is fitted with pressure gauges, open gauge cocks and
record pressure reading for future reference. Verify that the
pump is performing in accordance with parameters specified
on performance curve.
9. Check and record voltage, amperage per phase, and
kilowatts, if a wattmeter is available.
6.5 Voltage regulation
The motor will operate satisfactorily under the following
conditions for voltage and frequency variation, but not necessarily
in accordance with the standards established for operation under
rated conditions: The voltage variation may not exceed 10 %
above or below rating specified on the motor data plate.
The frequency variation may not exceed 5 % above or below
motor rating. The sum of the voltage and frequency variations
may not exceed 10 % above or below motor rating, provided the
frequency variation does not exceed 5 %.
6.6 Pump shutdown
The following shutdown procedures will apply in most normal
shutdowns for Grundfos Type VLSE pump. If pump will be
inoperative for an extended length of time, follow storage
procedures in Section IC. Always close the discharge gate valve
before stopping pump. Close valve slowly to prevent hydraulic
shock. Cut power to motor.
6.7 Short duration shutdown
For overnight or temporary shutdown periods under nonfreezing
conditions, the pump may remain filled with liquid. Make sure the
pump is fully primed before restarting. For short or frequent
shutdown periods under freezing conditions, keep fluid moving
within pump casing and insulate or heat pump exterior to prevent
freezing.
6.8 Extended period shutdown
For long shutdown periods, or to isolate the pump for
maintenance, lock-out power to pump and close suction gate
valve. If no suction valve is used and the pump has positive
suction head, drain all liquid from suction line to terminate liquid
flow into pump suction nozzle. Remove plugs in pump drain and
vent taps, as required, and drain all liquid from the pump volute
casing. If freezing conditions will exist during long shutdown
periods, completely drain the pump and blow out all liquid
passages and pockets with compressed air. Freezing of pump
liquid can also be prevented by filling the pump with antifreeze
solution.
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Never run the pump dry in the hope that it will
prime itself! Serious damage to the mechanical
seal will result.
Warning
In the interest of operator safety, the unit must
not be operated above the nameplate conditions.
Such operation could result in unit failure
causing injury to operating personnel.
Consult instruction book for proper operation
and maintenance of the pump and its supporting
components.
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Verify driver rotation prior to startup and
operation. Failure to do so can result in serious
damage to pump and driver if rotation is wrong.