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Beschikbare talen
Beschikbare talen
− To facilitate inspection and replacement, install the pump in an easily accessible position.
− The arrows on the pump body indicate the direction of flow. The use of gate valves on the suction and delivery pipes is recommended in
order to avoid draining the system in the event of repairs. In addition, provide a by-pass circuit between delivery and suction to ensure a
minimum of recirculation in the event that solenoid valves are used on the pipes, so as not to cause dangerous overheating.
− Ensure that the system is equipped with an air vent system and that the expansion tank (if fitted) is installed before the suction mouth.
When, on the other hand, the pump is installed on the delivery side of an open vessel circuit, make sure that the safety pipe is connected
before the pump.
− Mount the pump on the system without allowing the metal pipes to transmit excessive stresses or strains to the pump body, which could
lead to cracks and breakage.
− To prevent the transmission of noise or any vibrations, fit anti-vibration couplings to the suction and delivery mouths.
7.
ELECTRICAL CONNECTION
Strictly observe the wiring diagrams inside the terminal board box and those shown in the Tab. C at the end of the
booklet.
In the case of three-phase motors with star-delta starting, it must be ensured that the switching time between star and delta is as short as
possible and falls within table B at the end of the booklet.
Before accessing the terminal board and working on the pump, make sure that power has been switched off.
Check the mains voltage before making any connections. If it corresponds to the data plate, connect the wires to the terminal board, giving
priority to the earth wire.
The pumps must always be connected to an external switch.
The motors must be protected by motor protectors that are appropriately rated in relation to the current indicated on the data plate.
In systems where the twin version is envisaged, for the purposes of continuity of service, provide separate wiring and switches for each
individual pump.
8.
STARTING UP
Before starting the pump, check that:
− the pump has been properly primed, filling the pump body completely. This ensures that the pump immediately starts to
work regularly and that the seal (mechanical seal or stuffing box seal) is well lubricated. Dry operation causes irreparable
damage to the mechanical seal and the stuffing box seal;
− the auxiliary circuits have been correctly connected;
− all the moving parts have been protected with suitable safety systems;
− the electrical connection has been made as indicated previously.
8.1 Starting
Before starting, it is essential to fill the system with water and to vent the air. Vent the residual air from the pump body by inserting a hose
into the venting tap and unscrewing it slightly until only water comes out. This is to ensure that the mechanical seal is well lubricated and
that the pump starts running smoothly immediately.
Power up and check the correct direction of rotation which, looking at the motor from the fan side, should be clockwise. The check should
be carried out after the pump has been powered up by acting on the main switch with a fast start-stop sequence. If the direction of rotation
is reversed, invert any two phase leads, after having isolated the pump from the power mains.
When the hydraulic circuit has been completely filled with liquid, gradually open the delivery gate valve to the maximum permissible opening.
The energy consumption of the motor must be checked and compared with the value on the data plate, especially if the pump was
intentionally equipped with a motor with reduced power (check the design specifications).
With the electric pump in operation, check the supply voltage at the motor terminals, which must not differ by +/- 5% from the rated value.
8.2 Breaking in the mechanical seal
The faces of the mechanical seal are lubricated by the pumped liquid, which means that some leakage from the mechanical seal may occur.
If the pump is started up for the first time or if a new mechanical seal is installed, a certain break-in period is necessary before leakage is
reduced to a minimum. The time required depends on the operating conditions, i.e. if the operating conditions change, a new break-in period
will begin. Under normal conditions, the escaping liquid evaporates immediately. As a result, liquid leakage is invisible.
8.3 Stopping
If hot water is to be pumped, arrange that the pump can be stopped only after having excluded the source of heat and let sufficient time
elapse to allow the liquid temperature to drop to acceptable values, so as not to create excessive temperature increases inside the pump
body.
For a long period of inactivity, close the interception device on the intake pipe and, if supplied, all the auxiliary control connections. To
guarantee maximum system functionality it will be necessary to arrange for brief running periods (5 - 10 min) at intervals of 1 to 3 months.
If the pump is removed from the system and stored, proceed as indicated in par 4.1
ENGLISH
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