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PRECAUTIONS FOR USE OF THE INVERTER
4 PRECAUTIONS FOR USE OF THE INVERTER
The FR-D700 series is a highly reliable product, but using incorrect peripheral circuits or incorrect operation/handling methods
may shorten the product life or damage the product.
Before starting operation, always recheck the following items.
(1) Use crimping terminals with insulation sleeve to wire the power supply and motor.
(2) Application of power to the output terminals (U, V, W) of the inverter will damage the inverter. Never perform
such wiring.
(3) After wiring, wire offcuts must not be left in the inverter.
Wire offcuts can cause an alarm, failure or malfunction. Always keep the inverter clean.
When drilling mounting holes in an enclosure etc., take care not to allow chips and other foreign matter to enter the
inverter.
(4) Use cables of the appropriate size to make a voltage drop of 2% or less.
If the wiring distance is long between the inverter and motor, a main circuit cable voltage drop will cause the motor torque
to decrease especially at the output of a low frequency.
Refer to
page 7
for the recommended wire sizes.
(5) The total wiring length should be within the prescribed length.
Especially for long distance wiring, the fast-response current limit function may decrease, or the equipment connected to
the output side may malfunction. This is caused by a charging current due to the stray capacity of the wiring. Therefore,
note the overall wiring length.
(6) Electromagnetic wave interference
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 this case, install the FR-BIF optional capacitor
type filter (for use in the input side only) or FR-BSF01 line noise filter to minimize interference.
(7) Do not install a power factor correction capacitor, surge suppressor or capacitor type filter on the inverter
output side.
This will cause the inverter to trip or the capacitor and surge suppressor to be damaged. If any of the above devices are
connected, immediately remove them. When using capacitor type filter (FR-BIF) for a single-phase power input model,
make sure of secure insulation of T-phase, and connect to the input side of the inverter.
(8) For some short time after the power is switched off, a high voltage remains in the smoothing capacitor.
When accessing the inverter for inspection, wait for at least 10 minutes after the power supply has been switched off,
and then make sure that the voltage across the main circuit terminals P/+ and N/- of the inverter is no more than 30VDC
using a tester.
(9) A short circuit or earth (ground) fault on the inverter output side may damage the inverter modules.
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Fully check the insulation resistance of the circuit prior to inverter operation since repeated short circuits may damage
the inverter modules. These short circuits may be caused by peripheral circuit inadequacy, an earth (ground) fault
caused by wiring inadequacy, or reduced motor insulation resistance.
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Fully check the to-earth (ground) insulation and phase to phase insulation of the inverter output side before power-on.
Especially for an old motor or use in a hostile atmosphere, securely check the motor insulation resistance etc.
(10) Do not use the inverter input side magnetic contactor to start/stop the inverter.
Since repeated inrush currents at power ON will shorten the life of the converter circuit (switching life is about 1,000,000
times), frequent starts and stops of the MC must be avoided. Always use the start signal (turn ON/OFF STF, STR signal)
to start/stop the inverter.
(11) Across P/+ and PR terminals, connect only the brake resistor.
The brake resistor cannot be connected to the FR-D720-008 and 014, FR-D720S-008 and 014, FR-D710W-008 and
014. Do not connect a mechanical brake.
Leave terminals P/+ and PR open. Also, never short between P/+ and PR.
