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Provide for the possibility of draining the pump without
having to drain the entire system.
Install correctly any compensators for absorption of expansion
or impeding noise transmission.
Make sure gaskets do not protrude inside the pipes.
5.1. Suction pipe
When a pump is located above the water level
(suction lift
operation,
fig. 2 A
), fit a foot valve with a strainer, which must
always remain immersed.
The suction pipe must be perfectly airtight and be led upwards
in order to avoid air pockets.
When the liquid level on the suction side is above the pump
(inflow under positive suction head,
fig. 2 B
), fit a gate valve.
Follow local specifications if increasing network pressure.
Install a strainer on the suction side of the pump to prevent
foreign particles from entering the pump.
5.2 Delivery pipe
Install a gate valve in the delivery pipe to regulate flow-rate,
head and absorbed power.
Install a pressure gauge between the pump and the gate valve.
ATTENTION
: install a check valve between the pump and the
gate valve in order to avoid reverse flow after switching off the
pump unit and to protect the pump from water hammering.
With servo-operated shut-off devices, provide an air vessel or
other protection device against surge of pressure in the case of
sudden changes of flow rate.
6. Electrical connection
Electrical connection must be carried out only
by a qualified electrician in accordance with local
regulations.
Follow all safety standards.
The unit must be properly earthed (grounded).
Connect the earthing (grounding) conductor to the terminal with
the marking.
Compare the frequency and mains voltage with the name-plate
motor data and connect the supply conductors to the terminals
in accordance with the corresponding diagram inside the
terminal box.
ATTENTION
: with motor power rating ≥ 5.5 kW avoid direct
starting. Provide a control panel with star-delta starting or an
other starting device.
The motors with supply current directly
switched by thermally sensitive switches can
start automatically.
Install a
device for disconnection from the mains
(switch)
with a contact separation of at least 3 mm in all poles.
Install a suitable overload cutout in accordance with the rated
current.
Refer to any other instructions (if supplied) for use of the motor.
7. Starting
7.1. Preliminary checks
Make sure the coupling with the pump shaft turns freely when
rotated by hand (see
section 4.
).
Make sure the screws (64.25) of the coupling are tightened
(see
section 10.2.
).
Make sure the coupling guard (32.30) is fastened
on the lantern bracket.
7.2. Filling
ATTENTION: never run the pump dry, not even for a short
trial run.
Start the pump after filling it completely with liquid.
When the pump is located above the water level
(suction lift
operation,
fig. 2A
) or with a positive suction head which is too
low (less than 1 m) to open the non-return valve, fill the suction
pipe and the pump through the priming hole (1) (
fig. 3
).
In the case of vertical installation, remove the plug (2) during
the filling operation to vent the suction side. After the liquid has
been released, replace the plug (2). Proceed with filling until the
liquid spills out of the venting hole (1 ) in the upper cover. Top
up until the pump is completely vented before replacing the
plugs (1). In the case of horizontal installation, fill and vent
through the holes (1) in the pump casing (14.00).
When the liquid level on the suction side is above the
pump
(inflow under positive suction head,
fig. 2B
), fill the pump
by slowly and completely opening the inflow gate valve while
keeping the delivery gate valve and air vent holes (1), (2) (
fig.3
)
open to release the air.
During filling, keep the air vent holes (1)(2) open
only if the inflowing liquid presents no possible
danger on account of its nature, temperature or
pressure.
If necessary, install joints with a tap/valve device to holes 1 and
2, to control the outflow of the liquid and its direction of flow.
With a delivery pipe arranged horizontally, or lower than the
pump, keep the delivery gate valve closed during the filling
operation.
7.3. Starting and checking operations
Close the air vent holes (1), (2) (
fig.3
).
Start the pump with the delivery gate valve closed and with the
suction gate valve fully open. Immediately afterwards, gradually
open the delivery gate valve, adjusting the point of operation
within the limits indicated on the name plate.
A
B
6
3
5
2
7
4
5
7
1
5
1
5
3.93.113
1. Strainer
2. Foot valve
3. Check valve
4. Bypass valve
5. Gate valve
6. Pressure gauge
7. Supports and clamps for
pipelines
Fig. 2 Systems diagram
A = Suction lift operation
B = Positive suction head operation
(3)
(1) (2)
2)
1)
(3)
(3)
4.93.215
Fig.3 (1) Filling and air vent
(2) Suction side air vent
(3) Draining
8