Fuji Electric frenic mini series, User Manual

Page: 7 / 269

iv
Environ-
mental
conditions
Installation
location
Use the inverter in a location with an ambient temperature range of -10 to
50°C.
The inverter and braking resistor surfaces become hot under certain
operating conditions. Install the inverter on nonflammable material such as
metal.
Ensure that the installation location meets the environmental conditions
specified in Chapter 8, Section 8.5 "Operating Environment and Storage
Environment."
Installing a
molded case
circuit breaker
(MCCB) or earth
leakage circuit
breaker (ELCB)
Install a recommended molded case circuit breaker (MCCB) or an earth
leakage circuit breaker (ELCB) (with the exception of those exclusively
designed for protection from ground faults) in the primary circuit of the
inverter to protect the wiring. Ensure that the circuit breaker capacity is
equivalent to or lower than the recommended capacity.
Installing a
magnetic
contactor (MC) in
the secondary
circuit
If a magnetic contactor (MC) is mounted in the inverter's secondary circuit
for switching the motor to commercial power or for any other purpose,
ensure that both the inverter and the motor are fully stopped before you
turn the MC on or off.
Installing a
magnetic
contactor (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 fault 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 facility 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 cable, 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).
Discontinuance of
power-factor
correcting
capacitor
Do not mount power factor correcting capacitors in the inverter primary
circuit. (Use the DC reactor to improve the inverter power factor.) Do not
use power factor correcting capacitors in the inverter output circuit. An
overcurrent trip will occur, disabling motor operation.
Reducing noise
Use of a filter and shielded wires are typical measures against noise to
ensure that EMC directives are met. Refer to Appendices, App. A
"Advantageous Use of Inverters (Notes on electrical noise)" for details.
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 phase-advancing 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 the FRENIC-Mini
Instruction Manual, Chapter 7, Section 7.4 "Insulation Test."