Wilo Medana CH1-LC Notice De Montage Et De Mise En Service page 26

en
7.4 Electrical connection
7.5 Operation with a frequency con-
verter
8 Commissioning
8.1 Filling and deaeration
26
Commissioning
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The pipe cross-section must be at least equal to the diameter of the suction port on
the pump housing.
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The installation of a non-return valve in the discharge pipe is recommended to pro-
tect the pump against pressure surges.
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If connected directly to the public potable water mains, the suction pipe socket
must also be fitted with a non-return valve and a stop valve.
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If connected indirectly via a tank, the suction pipe socket must be fitted with a suc-
tion strainer to stop impurities from entering the pump, and a non-return valve.
DANGER
Risk of electrocution
In case of a non-compliant electrical connection, there is a risk of electrocution.
■ Have the electrical connection established by an electrician approved by the local
energy supply company in accordance with local regulations.
■ Prior to the electrical connection, the pump must be voltage-free and protected
against unauthorised restart.
■ To ensure safe installation and operation, the pump must be earthed correctly
with the earth terminals of the power supply (Fig. 6).
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Verify that the rated current, voltage and frequency used match the information on
the pump's rating plate.
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The pump must be connected to the power supply using a cable fitted with a socket
or a main switch.
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The three-phase motors must be connected to an authorised protection system.
The setting rated current must match the value indicated on the motor's sticker.
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Single-phase motors are equipped as standard with thermal motor protection, which
stops the pump if the permissible winding temperature is exceeded and starts it up
again automatically once it has cooled down.
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The connection cable must be placed in such a way that it never comes into contact
with the main sewer system and/or the pump housing and motor frame.
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The pump/installation should be earthed in accordance with local regulations. A cir-
cuit breaker can be used as additional protection.
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The power supply connection must comply with the wiring diagram (Fig. 6).
WARNING
Risk of injuries and water penetration in the connection area
Observe the tightening torques (Fig. 7)
Observe the diameter value of the cable gland wiring to ensure IP55 protection (see
Fig. 7 [E]):
M20 = min. Ø6 – max. Ø12
M25 = min. Ø13 – max. Ø18
It is possible to adjust the speed of the pump using a frequency converter. The limit val-
ues for adjusting the speed are as follows:
40 % rated ≤ n ≤ 100 % rated. The installation and commissioning instructions for the
frequency converter must be followed when connecting it and starting operation. To
avoid overloading the motor winding, which could lead to damage and unwanted noise,
the frequency converter cannot produce voltage rise speed stages higher than 500 V/μs
or voltage spikes U > 650 V.
To make such voltage rise speed stages possible, an LC filter (motor filter) should be in-
stalled between the frequency converter and the motor. The specifications for this filter
must be provided by the manufacturer of the frequency converter / filter. Control
devices with a frequency converter delivered by Wilo have an integrated filter.
Check whether the water level in the tank and the inlet pressure are sufficient.
WILO SE 02/2021