Fuji Electric FRENIC-ECO, Инструкция по эксплуатации

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xi
Installing an
MCCB or
RCD/GFCI
Install a recommended molded case circuit breaker (MCCB) or
residual-current-operated protective device (RCD)/a ground fault circuit
interrupter (GFCI) (with overcurrent protection) in the primary circuit of the
inverter to protect the wiring. Ensure that the circuit breaker rated current is
equivalent to or lower than the recommended rated current.
Installing an MC
in the secondary
circuit
If a magnetic contactor (MC) is mounted in the inverter's output
(secondary) circuit for switching the motor to commercial power or for any
other purpose, ensure that both the inverter and the motor are completely
stopped before you turn the MC ON or OFF.
Remove the magnet contactor (MC) already installed and built-in surge
suppressor from the inverter's output (secondary) circuit before installing
the MC to switch the motor power.
Installing an MC
in the primary
circuit
Do not turn the magnetic contactor (MC) in the primary circuit ON or OFF
more than once an hour as an inverter failure may result.
If frequent starts or stops are required during motor operation, use
(FWD)/(REV) signals or the RUN/STOP key.
Protecting the
motor
The electronic thermal function of the inverter can protect the motor. The
operation level and the motor type (general-purpose motor, inverter motor)
should be set. For high-speed motors or water-cooled motors, set a small
value for the thermal time constant and protect the motor.
If you connect the motor thermal relay to the motor with a long wire, a
high-frequency current may flow into the wiring stray capacitance. This
may cause the relay to trip at a current lower than the set value for the
thermal relay. If this happens, lower the carrier frequency or use the output
circuit filter (OFL).
Use of
power-factor
correcting
capacitor Do not mount power-factor correcting capacitors in the inverter’s primary
circuit. (Use the DC reactor to improve the inverter power factor.) Do not
use power-factor correcting capacitors in the inverter’s output (secondary)
circuit. An overcurrent trip will occur, disabling motor operation.
Use of surge
suppressor Do not connect a surge suppressor to the inverter's output (secondary)
circuit.
Reducing noise
Use of a filter and shielded wires is typically recommended to satisfy EMC
Directives.
Measures against
surge currents
If an overvoltage trip occurs while the inverter is stopped or operated under
a light load, it is assumed that the surge current is generated by open/close
of the power-factor correcting capacitor in the power system.
* Connect a DC reactor to the inverter.
Combina-
tion with
peripheral
devices
Megger test
When checking the insulation resistance of the inverter, use a 500 V
megger and follow the instructions contained
in Chapter 7, Section 7.5
"Insulation Test."
Control circuit
wiring length When using remote control, limit the wiring length between the inverter and
operator box to 67ft (20m) or less and use twisted pair or shielded wire.
Wiring length
between inverter
and motor
If long wiring is used between the inverter and the motor, the inverter will
overheat or trip as a result of overcurrent (high-frequency current flowing
into the stray capacitance) in the wires connected to the phases. Ensure
that the wiring is shorter than 164ft (50m). If this length must be exceeded,
lower the carrier frequency or mount an output circuit filter (OFL).
Wiring size
Select wires with a sufficient capacity by referring to the current value or
recommended wire size.
Wiring type
When several inverters drive motors, do not use one multicore cable in
order to connect several inverters with motors.
Wiring
Grounding Securely ground the inverter using the grounding terminal.