Operation With Frequency Converter - Wilo -MultiVert-MVI 1-6 Serie Instrucciones De Instalación Y Funcionamiento

• Connection to the mains must be carried out in
accordance with the plan of terminal connections
for rotary or alternating current in the terminal
box of the pump (Fig. 4).
• The terminal box can be better positioned by
rotating the motor through steps of 90°. To do
this, remove the clutch guard (Fig. 1, 2) and
loosen the connecting screws (Fig. 1, 1) of the
light and the motor flange. When assembling
the clutch guard, do not forget to tighten
the safety screw.

5.3 Operation with frequency converter

The speed of the pump can be controlled when
connected to a frequency converter. Speed control
limits: 40%n ≤ n ≤ 100%n
nom
See Installation and Operating Instructions of the
frequency converter for connection and operation.
To avoid overloading the motor coil to the extent
that it is damaged and to avoid increased noise
levels, the frequency converter must not produce
speeds due to increased voltage of over 2500 V/µs
and spikes of û > 850 V. If such speeds due to in-
creased voltage are possible, an LC filter (motor fil-
ter) should be installed between the frequency
converter and the motor. The filter must be de-
signed by the manufacturer of the frequency con-
verter or filter.
In control devices with frequency converters sup-
plied by Wilo, the
filter is already installed.
6. Commissioning
In order to protect the axial face
WARNING!
seal, the pump must not run dry.
• Close both isolating valves and open the vent
screw (Fig. 2, 5) by one and a half or two turns.
• Slowly open the isolating valve (Fig. 2, 2) at the
inlet until the air has escaped from the vent
screw and the fluid to be pumped comes out.
The escaping air will be clearly heard hissing.
Tighten the vent screw.
• Slowly open the isolating valve at the outlet
(Fig. 2, 3). The manometer installed at the outlet
should be checked for any possible pressure
instabilities, indicated by a flickering manometer
pointer. If the pressure is unstable, allow more
air to escape.
When the temperature of the liquid being pumped
is high and the system is pressurised, any flow es-
caping from the vent screw can cause scalding and
injuries. The vent screw should therefore be loosen
only slightly.
• When used for the first time, if it is to be used to
pump drinking water the system must be flushed
through, so that any dirty water present will not
contaminate the drinking water supply.
• Checking direction of rotation (only for rotary
current motors): Check that the pump rotates in
the direction indicated by the arrow on the pump
latern by switching on for a short time. If this is
not the case, interchange 2 phases in the termi-
nal box.
WILO SE 11/2010
.
nom
• For pumps with a star or triangular circuit starting
current, the connections of two coils must be
interchanged, e.g. U1 with V1 and U2 with V2.
It is not necessary to check the direction of
rotation with AC motors.
• If the fluid temperature is too high, steam may
form which may damage the pump. The pump
must therefore not run with the valve closed for
longer than 10 minutes when pumping cold
water or for longer than five minutes when
pumping fluid where >60 °C.
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We recommend that the flow rate does not drop
to below 10 % of the nominal flow rate so as to
avoid a build up of steam in the pump.
• If there is a build up of steam, this should be
allowed to escape by carefully opening the vent
screw.
The pump, including the motor, may reach
operating temperatures of
should be taken when touching the pump.
7. Maintenance
Before carrying out any maintenance work, switch
off the unit and ensure that it cannot be switched on
again by unauthorized people. Never carry out work
on a running pump.
• During the running-in period, there may be some
dripping from the axial face seal. Should a more
significant leak occur as a result of substantial
wear, have the axial face seal replaced by a spe-
cialist.
• Increased bearing noise and unusual vibrations
indicate a worn bearing. In this case, have the
bearing replaced by a specialist.
• If the pump is exposed to frost, the pump and
pipework must be emptied in the cold season.
Close the isolating valve and open the drain valve
(Fig. 2, 6) and the vent screw (Fig. 2, 5) of the
pump.
The isolating valve must be closed before the drain
valve is opene
• If placed in a frost-free location, the pump does
not have to be emptied, even if it is out of service
for a long period.
Figures:
1. Cross-section of the pump
2. Whole assembly in inlet phase with reference numbers
3. Drawing showing principal dimensions
4. Terminal connection plans
English
>100 °C, so care
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