Checklist Before Starting Operation - Mitsubishi Electric FR-F806-E Hardware Instruction Manual

3.6

Checklist before starting operation

The FR-F800 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.
Checkpoint
Crimping terminals are insulated.
The wiring between the power
supply (R/L1, S/L2, T/L3) and the
motor (U, V, W) is correct.
No wire offcuts are left from the
time of wiring.
The main circuit cable gauge is
correctly selected.
The total wiring length is within the
specified length.
Countermeasures are taken
against EMI.
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
occurring.
The circuit is not configured to use
the inverter's input-side magnetic
contactor to start/stop the inverter
frequently.
The voltage applied to the inverter
I/O signal circuits is within the
specifications.
When using the electronic bypass
operation, electrical and
mechanical interlocks are provided
between the electronic bypass
contactors MC1 and MC2.
Countermeasure
Use crimping terminals with insulation sleeves to wire the power supply and
the motor.
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 a wall etc., take caution not to allow chips and
other foreign matters 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, the 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.
Such installation will cause the inverter to trip or the capacitor and surge
suppressor to be damaged. If any of the above devices is connected,
immediately remove it.
For some 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
inverter module.
Fully check the insulation resistance of the circuit prior to inverter operation
since repeated short circuits caused by peripheral circuit inadequacy or a
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, make sure to 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/OFF the inverter's start signals (STF, STR) to run/stop the
inverter.
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.
When using a switching circuit as shown below, chattering due to mis-
configured sequence or arc generated at switching may allow undesirable
current to flow in and damage the inverter. Mis-wiring may also damage the
inverter. (The commercial power supply operation is not available with PM
motors.)
Power
R/L1
supply
S/L2
T/L3
Inverter
If switching to the commercial power supply operation while a failure such as
an output short circuit has occurred between the magnetic contactor MC2 and
the motor, the damage may further spread. If a failure has occurred between
the MC2 and the motor, a protection circuit such as using the OH signal input
must be provided.
PRECAUTIONS FOR USE OF THE INVERTER
Checklist before starting operation
MC1
Interlock
U
IM
V
MC2
W
Undesirable current
Refer Check
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