EBARA 4WN Manual De Instrucciones página 9

The starting torque of the pump motor tends to give a twist
which could cause the pump shell to rub against the inside
walls of the bore casing - especially if rigid PVC or polythene
pipe is used. Torque stops can be obtained and installed to
dampen this twisting.
7.2. SAFETY CABLE
As a precautionary measure, a safety line should be con-
nected to all pumps regardless of the type of drop pipe
used. This line should be fastened to the pump and at the
top of the bore casing.
7.3. DEPTH OF INSTALLATION
For the maximum allowable submergence consult the motor
specifications from the motor supplier. Ensure that the
pump is installed at least one (1) metre, preferably 3 metres
above the bottom of the bore, and one (1) metre below the
maximum draw down level..
WARNING: If during the initial operation the pump lowers the bore
water level down to below the suction inlet it will be necessary to
lower the pump, where feasible or install a level probe protection
device to prevent the pump from running under aerated water
conditions.
NOTE: OVER PUMPING OF THE BORE (AERATED WATER)
WILL CAUSE DAMAGE TO PUMP AND OR MOTOR NOT
COVERED BY GUARANTEE.
Before lowering the pump unit, smooth out any rough
spots or sharp edges on the top lip of the bore casing
to prevent damage to the pump or power cables when
lowering the unit into the bore.
7.4. CHECK VALVE
All 4WN submersible deep well pumps are supplied with a
check valve, and no additional check valves are required
for open discharge conditions up to a maximum of 80
metres head. For installations greater than 80 metres
head, or when used as a pressure system, it is
recommended that an additional check valve is fitted
approximately no more than 60 metres vertically above the
pump and every 60 metres vertically thereafter. The fitting
of this check valve will limit potential water hammer and
consequent pump damage.
7.5. PRESSURE SYSTEM INSTALLATION AND PUMP
CONTROLS
4WN submersible deep well pumps may be used as a pres-
sure system in conjunction with pressure tanks providing a
suitable draw off capacity. When selecting a pressure tank,
make sure that the rated tank pressure is at least 10% grea-
ter than the pump pressure at the bore head and the tank
draw off capacity is large enough to limit pump starts to an
absolute maximum of those listed in the motor's manual.
While small capacity tanks may be used, extreme care must
be taken to ensure the pump unit does not 'cycle'. It may be
necessary to fit more than one pressure tank to provide the
required draw off or to help prevent pump cycling.
The installation of a 'drilled check valve' to the pressure tank
may assist in the prevention of pump 'cycling' problems.
For further information on these contact your EBARA Pumps
Europe S.p.A Dealer.
NOTE: Any automatic switching of the pump giving excessive starts
per hour will shorten the life of the pump and damage caused may
effect warranty cover.
7.6. DISMANTLING
The following must be done when moving or dismantling the
motor pump:
a) disconnect the electric supply;
b) remove the delivery and suction pipes (where present) if too
long or bulky;
c) if present, unscrew the screws that secure the motor-driven
pump to its supporting surface;
d) if present, hold the power cable;
e) lift the motor-driven pump using equipment suitable to the
pump weight and dimensions (refer to the plate).
7.7. TRANSPORTATION
The motor-driven pump is packed in a carton or can be fixed
to a wooden pallet, if pump weight and dimensions allow it.
Transportation should not, in any case, present any particular
problems.
Verify the total weight stamped on the box.
7.8. STORAGE
a) The product must be stored in a covered and dry place,
far away from heat sources and protected against dirt and
vibrations.
b) Protect the product against damp conditions, heat sources
and mechanical damage.
c) Do not place heavy objects on the packaging.
d) The product must be stored at an ambient temperature
between +5°C and +40°C (41°F – 104°F) with a relative
humidity of 60%.
8. TYPICAL SUBMERSIBLE INSTALLATION
A. PUMP CONNECTED FOR MANUAL OPERATION.
B. PUMP INSTALLED AS AN AUTOMATIC PRESSURE SYSTEM
INCORPORATING PRESSURE TANK AND PRESSURE
SWITCH.
WARNING: Failure to use correct starting equipment
and overloads may damage your submersible motor.
This damage may not be covered by warranty.
Alternative systems may be connected directly into the supply,
provided the switching device used has an adequate current
rating and an approved overload protection. If the current rating
of the switch is not adequate, a contactor must be wired into
the supply and the switching device used to control the
contactor's coil.
ALL THREE PHASE MOTORS MUST BE CONNECTED
WITH APPROVED OVERLOADS.
EN
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