Operation With Frequency Converter; Electrical Connection - Wilo Helix-V 2 Notice De Montage Et De Mise En Service

counterflange accessories supplied with the
product.
CAUTION!
Tightening of screws or bolts must not exceed
10 daN.m.
Use of impact wrench is prohibited.
- The circulation sense of the fluid is indicated on
the identification label of the pump.
- Pump must be installed in such a way that it is
not stressed by the pipework. The pipes must be
attached so that the pump does not bear their
weight.
- It is recommended that isolation valves be
installed on the suction and discharge side of the
pump.
- Use of expansion joints may mitigate noise and
vibration of the pump.
- As regards the nominal cross-section of the suc-
tion pipe, we recommend a cross-section at least
as large as that of the pump connection.
- A check valve could be placed on the discharge
pipe in order to protect the pump against ham-
mer shock.
- For direct connection to a public drinking water
system, the suction pipe must also have a check
valve and a guard valve.
- For indirect connection via a tank, the suction
pipe must have a strainer to keep any impurities
out of the pump and a check valve.
7.4 Motor connection for bare-shaft pump
(without motor)
- Remove coupling guards.
NOTE: Coupling guards can be removed without
entirely unscrewing screws.
- Install the motor on the pump by using screws
(FT lantern size – see product designation) or
bolts, nuts and handling devices (FF lantern size
– see product designation) provided with the
pump : check motor power and dimension in
WILO catalogue.
NOTE: Depending on fluid characteristics, motor
power could be modified. Contact WILO
Customer Services if needed.
- Close the coupling guards by screwing all screws
provided with the pump.

7.5 Electrical connection

WARNING! Electrical shock hazard!
Dangers caused by electrical energy must be
excluded.
• Electrical work by a qualified electrician only!
• All electrical connections must be performed
after the electrical supply has been switched off
and secured against unauthorized switching.
• For safe installation and operation a proper
grounding of the pump to the power supply's
grounding terminals is required.
- Check that operating current, voltage and fre-
quency used comply with motor plating data.
WILO SE 09/2011
- The pump must be connected to the power sup-
ply by a solid cable equipped with a grounded
plug-connection or a main power switch.
- Three-Phase motors must be connected to an
approved motor starter. The set nominal current
must correspond to the electrical data on the
pump motor name plate
- The supply cable must be laid so that it never
touches the pipework and/or the pump and
motor casing.
- The pump/installation should be grounded in
compliance with local regulations. A ground fault
interrupter can be used as extra protection.
- The connection to the network must be in
accordance with the connection plan (Fig. 5).

7.6 Operation with frequency converter

- Motors used can be connected to a frequency
converter in order to adapt pump performance to
duty point.
- The converter must not generate voltage peaks
at motor terminals higher than 850V and dU/dt
slope higher than 2500 V/µs.
- In case of higher value, an appropriate filter must
be used : contact converter manufacturer for this
filter definition and selection.
- Strictly follow instructions provided by the con-
verter manufacturer data sheet for installation.
- Minimum variable speed should not be set below
40% of pump nominal speed.
8. Start up
8.1 System filling - Venting
CAUTION! Possible damage of the pump!
Never operate the pump dry.
The system must be filled before starting the
pump.
8.1.1 Air evacuation process – Pump with sufficient
supply pressure (Fig. 3)
- Close the two guard valves (2, 3).
- Unscrew the air bleed screw from filling plug (6a).
- Slowly open the guard valve on the suction side (2).
- Retighten the air-bleed screw when air escapes
at the air bleed screw and the pumped liquid
flows (6a).
WARNING!
When the pumped liquid is hot and the pressure
high, the stream escaping at the air bleed screw
may cause burns or other injuries.
- Open the guard valve on the suction side com-
pletely (2).
- Start the pump and check if direction of rotation
matches the one printed on pump plating
CAUTION!
A wrong direction of rotation will cause bad pump
performances and possibly coupling damage.
- Open the guard valve on the discharge side (3).
English
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