Checklist before starting operation
The FR-A800 series inverter is a highly reliable product, but incorrect peripheral circuit making or operation/handling method
may shorten the product life or damage the product. Before starting operation, always recheck the following points.
Crimp terminals are insulated.
The wiring between the power
supply (terminals R/L1, S/L2, T/
L3) and the motor (terminals U, V,
W) is correct.
No wire offcuts are left from the
time of wiring.
The main circuit cable gauge is
The total wiring length is within the
Countermeasures are taken
On the inverter's output side, there
is no power factor correction
capacitor, surge suppressor, or
radio noise filter installed.
When performing an inspection or
rewiring on the product that has
been energized, the operator has
waited long enough after shutting
off the power supply.
The inverter's output side has no
short circuit or ground fault
The circuit is not configured to use
the inverter's input-side magnetic
contactor to start/stop the inverter
A mechanical brake is not
connected to terminals P/+ and
The voltage applied to the inverter
I/O signal circuits is within the
Use crimp terminals with insulation sleeves to wire the power supply and the
Application of power to the output terminals (U, V, W) of the inverter will damage
the inverter. Never perform such wiring.
Wire offcuts can cause an alarm, failure or malfunction. Always keep the inverter
clean. When drilling mounting holes in an enclosure etc., take caution not to
allow chips and other foreign matter to enter the inverter.
Use an appropriate cable gauge to suppress the voltage drop to 2% or less. If
the wiring distance is long between the inverter and motor, a voltage drop in the
main circuit will cause the motor torque to decrease especially during the output
of a low frequency.
Keep the total wiring length within the specified length. In long distance wiring,
charging currents due to stray capacitance in the wiring may degrade the fast-
response current limit operation or cause the equipment on the inverter's output
side to malfunction. Pay attention to the total wiring length.
The input/output (main circuit) of the inverter includes high frequency
components, which may interfere with the communication devices (such as AM
radios) used near the inverter. In such case, activate the EMC filter (turn ON the
EMC filter ON/OFF connector) to minimize interference.
Doing so will shut off the inverter output or damage the capacitor or surge
suppressor. If any of the above devices is connected, immediately remove it.
For a short time after the power-OFF, a high voltage remains in the smoothing
capacitor, and it is dangerous. Before performing an inspection or rewiring, wait
10 minutes or longer after the power supply turns OFF, then confirm that the
voltage across the main circuit terminals P/+ and N/- of the inverter is low enough
using a tester, etc.
• A short circuit or ground fault on the inverter's output side may damage the
• Fully check the insulation resistance of the circuit prior to inverter operation
since repeated short circuits caused by peripheral circuit inadequacy or an
earth (ground) fault caused by wiring inadequacy or reduced motor insulation
resistance may damage the inverter module.
• Fully check the to-earth (ground) insulation and phase-to-phase insulation of
the inverter's output side before power-ON. Especially for an old motor or use
in hostile atmosphere, securely check the motor insulation resistance, etc.
Since repeated inrush currents at power ON will shorten the life of the converter
circuit, frequent starts and stops of the magnetic contactor must be avoided.
Turn ON or OFF the inverter's start (STF/STR) signal to run or stop the inverter.
To terminals P/+ and PR, connect only an external brake resistor.
Application of a voltage higher than the permissible voltage to the inverter I/O
signal circuits or opposite polarity may damage the I/O devices. Especially check
the wiring to prevent the speed setting potentiometer from being connected
incorrectly to short circuit terminals 10E and 5.
3. PRECAUTIONS FOR USE OF THE INVERTER
3.6 Checklist before starting operation