GB
MPSU Rev1 - Operating Instructions
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12.3 TAB 1).
When extension cables are used, make sure the cable
wires are of adequate size to avoid voltage drops. For
connection of cables in a well, use thermo-shrinking
sheathes or other methods for submersed cables.
ATTENTION: When the pump is fed by a
frequency converter, the minimum frequency
should not fall below 25 Hz and in any case the
total head of the pump should never be lower
than 2 m.
6.5.1. Single-phase pumps MPSUM
OFF
Supplied with incorporated capacitor and thermal
protector, with plug.
Connect the plug to a socket with an earth lead.
The motor will stop if overheating is detected. When
the windings cool down (after 2 to 4 minutes), the
thermal protector enables re-starting.
Electrical diagram (par. 12.2)
6.5.2. Three-phase pumps MPSU
OFF
Install in the control box an overload-protective device
in accordance curve type D with the name-plate
current.
7. STARTUP AND OPERATION
7.1. Preliminary checks before start-up of the
pump
Do not start-up the device in case of damaged parts.
7.2. First starting
OFF
ATTENTION: never run the pump dry. Start the
pump after filling it completely with liquid.
When the pump is located above the water level
(suction lift operation par. 12.1 fig. 1A) or with a
positive suction head which is too low (less than 1 m)
to open the non-return valve, fill the pump through the
priming hole.
When the liquid level on the suction side is above
the pump (inflow under positive suction head par.
12.1 fig. 1B), fill the pump by opening the suction gate
valve slowly and completely, keeping the delivery gate
valve open to release the air.
i
With a three-phase power supply make sure
the direction of rotation is correct.
To check this close the discharge valve and measure
the closed valve pressure with a pressure gauge
mounted between the valve and the pump discharge,
or visually check the flow-rate.
Switch off power, invert the connections of two phases
on the control panel, re-start and check the pressure or
flow rate capacity again.
The correct direction of rotation will provide a
considerably greater and easily distinguishable
pressure and delivery capacity.
Check that the pump works within its field of perfor-
mance and that the absorbed current shown on the
name-plate is not exceeded. Otherwise adjust the
delivery gate valve or the setting of any pressure
switches.
If a priming loss occurs (interruption of delivery flow)
or if a pressure oscillation is indicated by the pressure
gauge, make sure all the suction pipe couplings are
perfectly sealed and tighten the two sealed plugs on
the pump casing.
Never run the pump for more than five
minutes with a closed gate valve.
Prolonged operation without a change of water in the
pump causes dangerous increases of temperature and
pressure.
7.2.1. Construction with float switch:
The float switch, connected directly to the pump,
controls starting and stopping.
Check that the float switch is free from any obstacle. If
necessary, adjust the float-switch cable.
Execessive cable length may cause the motor to
overheat and the pump to run dry.
7.2.2. Construction without float switch:
If there is no air vent valve in systems with a check
valve, the minimum immersion depth at first start-up
must be 300 mm.
An air vent valve must be used in systems with an
immersed delivery outlet.
Do not start the pump with a completely closed shutoff
gate valve.
Never take the pump out of the water while the pump
is still operating.
7.3. Switch off of the pump
ON
The appliance must be switch off every time
there are faults. (see troubleshooting).
The product is designed for a continuous duty, the
switch off is performed by disconnecting the power
supply by means the expected disconnecting devices.
(see paragraph “6.5 Electrical connection”).
8. MAINTENANCE
Before any operations it's necessary to disconnect the
power supply.
If required ask to an electrician or to an expert
technician.
Every maintenance operations, cleaning or
reparation executed with the electrical system
under voltage, it could cause serious injuries
to people.
A possible replacement of the cable or the level
switch must be carried out by an authorised
Calpeda service workshop.
If the supply cord is damaged, it must be
replaced by the manufacturer, its service agent
or similarly qualified persons in order to avoid
a hazard.
In case of extraordinary maintenance, or maintenance
operations that require part-removing, the operator
must be a qualified technician able to read schemes
and drawings.
