xiii
Discontinuance
of power-factor
correcting ca-
pacitor
Do not mount power-factor correcting capacitors in the in-
verter’s 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.
Discontinuance
of surge killer
Do not connect a surge killer to the inverter's 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 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
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 20 m or less and use twisted
pair or shielded cable.
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 50 m. 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
Do not use one multicore cable in order to connect several
inverters with motors.
Wiring
Grounding
Securely ground the inverter using the grounding terminal.
Driving gen-
eral-purpose
motor
Select an inverter according to the nominal applied motor
listed in the standard specifications table for the inverter.
When high starting torque is required or quick acceleration or
deceleration is required, select an inverter with a capacity
one size greater than the standard.
Selecting
inverter
capacity
Driving special
motors
Select an inverter that meets the following condition:
Inverter rated current > Motor rated current
Transpor-
tation and
storage
When exporting an inverter built in a panel or equipment, pack them in a previously
fumigated wooden crate. Do not fumigate them after packing since some parts
inside the inverter may be corroded by halogen compounds such as methyl bro-
mide used in fumigation.
When packing an inverter alone for export, use a laminated veneer lumber (LVL).
For other transportation and storage instructions, see Chapter 1, Section 1.3
"Transportation" and Section 1.4 "Storage Environment."
