Wilo Atmos GIGA-I Einbau- Und Betriebsanleitung Seite 61

W2 U2
PTC
U1 V1
L1 L2
Fig. 14: Δ connection
Installation and operating instructions • Wilo-Atmos GIGA-I/-D/-B • Ed.01/2023-06
• When connecting an external frequency converter, observe the corresponding installation
and operating instructions! If necessary, carry out additional earthing due to higher leak-
age currents.
• The motor must be secured against overloading by a motor protection switch or by the
PTC thermistor tripping unit (accessory).
Standard pumps on external frequency converters
If standard pumps are used on external frequency converters, the following aspects have to
be considered regarding the insulation system and current-insulated bearings:
400 V power supply
The motors used by Wilo for glanded pumps are suitable for operation on external frequency
converters.
It is strongly recommended to set up and operate the installation in compliance with
IEC TS 60034-25:2014. Due to the rapidly advancing development in the field of frequency
converters, WILO SE does not guarantee fault-free use of the motors on third-party convert-
ers.
500 V/690 V power supply
The motors which Wilo uses as standard for glanded pumps are not suited to be used on ex-
ternal frequency converters with 500 V/690 V.
For use in 500 V or 690 V mains, motors with appropriate winding and reinforced insulation
system are available. This must be explicitly stated when ordering. The overall installation
must comply with IEC TS 60034-25:2014.
Current-insulated bearings
Due to increasingly fast switching processes of the frequency converter, drops in voltage can
occur across the motor bearing even with motors of lower power. In case of premature
breakdown due to bearing current, use current-insulated bearings!
Always observe the following instructions when connecting the frequency converter to the
motor:
• Observe the installation notes of the frequency converter manufacturer.
• Observe the rise times and peak voltages depending on the cable length in the respective
installation and operating instructions of the frequency converter.
• Use an appropriate cable with a sufficient cross-section (max. 5 % voltage loss).
• Connect the correct shielding according to the recommendation of the frequency con-
verter manufacturer.
• Lay the data cables (e.g. PTC analysis) separately from the mains cable.
• If necessary, use a sine filter (LC) in consultation with the frequency converter manufac-
turer.
Setting the motor protection switch:
• Set according to the rated motor current specified on the rating plate of the motor.
Y-Δ starting: If the motor protection switch is switched in the supply line to a Y-Δ con-
V2
tactor combination, adjust the switch as for direct starting. If the motor protection switch
is switched in a thread of the motor supply line (U1/V1/W1 or U2/V2/W2), set the motor
protection switch to the value 0.58 x rated motor current.
W1
• From 5.5 kW, the motor is equipped with PTC thermistor sensors.
• Connect the PTC thermistor sensors to the PTC thermistor tripping unit.
L3
NOTICE
The connection diagram for electrical connections is in the terminal box
cover.
CAUTION
Risk of property damage!
Only a maximum voltage of 7.5 V DC may be applied to the PTC thermistor
sensor terminals. A higher voltage will destroy the PTC thermistor sensor.
en
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