Frenic 5000VG7S Series, Инструкция по эксплуатации

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(2) Inverter output terminals (U, V, and W)
1) Connect three-phase motor leads to the inverter output terminals, U, V, and W with care not to connect a
wrong phase.
2) Do not connect a phase advancing capacitor or surge absorber (suppressor) to the inverter output
terminals.
3) If the wiring between the inverter and the motor is too long, a high-frequency current will run through the
wiring due to floating capacity to trip the inverter because of overcurrent, increase the leakage current,
and/or deteriorate the current indication accuracy. Therefore, the motor wiring length should not exceed
50m for 3.7kW or lower inverters or 100m for others, as a guide.
Connect the optional output circuit filter (OFL filter) if the wiring is too long.
4) When you use a motor with an encoder, limit the wiring distance between your inverter and motor to 100
m or less.
This limit is due to encoder characteristic. When the distance exceeds 100 m, you need an arrangement
such as inserting an isolation converter.
Without output circuit filter
When two or more motors are to be driven, the total length of wirings to those motors should not exceed 50m
for 3.7kW or lower inverters or 100m for 5.5kW or higher ones.
With output circuit filter
When two or more motors are to be driven, the total length of wirings to those motors should not exceed
400m.
Note:
When a thermal relay is used between the inverter and the motor, especially for 400V series, the
thermal relay may malfunction even with a wiring length less than 50m. In this case, connect an
OFL filter or reduce the inverter operation noise (carrier frequency) using function code F26 (motor
sound (carrier frequency)).
· Driving a 400V motor with an inverter
If a motor is driven with a PWM inverter, the surge voltage generated by switching inverter elements is
overlapped as applied to the motor terminals. Especially for 400V motors, the motor insulation may be
deteriorated by the surge voltage if the motor wiring is too long. Therefore, any of the following measures
should be taken when a 400V motor is to be driven with an inverter.
1) Use a motor with reinforced insulation (all the Fuji Electric's general-purpose motors have reinforced
insulation).
2) Connect the optional output circuit filter (OFL filter) to the inverter output terminals.
3) Shorten the wiring between the inverter and the motor as short as possible (to10 to 20m or less).