Fuji Electric FRENIC-MEGA, Инструкция по эксплуатации

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Noise reduction
If noise generated from the inverter affects other devices, or that generated from peripheral equipment causes the inverter to
malfunction, follow the basic measures outlined below.
(1) If noise generated from the inverter affects the other devices through power wires or grounding wires:
- Isolate the grounding terminals of the inverter from those of the other devices.
- Connect a noise filter to the inverter power wires.
- Isolate the power system of the other devices from that of the inverter with an insulated transformer.
- Decrease the inverter's carrier frequency (F26).
(2) If induction or radio noise generated from the inverter affects other devices:
- Isolate the main circuit wires from the control circuit wires and other device wires.
- Put the main circuit wires through a metal conduit pipe, and connect the pipe to the ground near the inverter.
- Install the inverter into the metal panel and connect the whole panel to the ground.
- Connect a noise filter to the inverter's power wires.
- Decrease the inverter's carrier frequency (F26).
(3) When implementing measures against noise generated from peripheral equipment:
- For inverter's control signal wires, use twisted or shielded-twisted wires. When using shielded-twisted wires, connect the
shield of the shielded wires to the common terminals of the control circuit.
- Connect a surge absorber in parallel with magnetic contactor's coils or other solenoids (if any).
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Leakage current
A high frequency current component generated by insulated gate bipolar transistors (IGBTs) switching on/off inside the inverter
becomes leakage current through stray capacitance of inverter input and output wires or a motor. If any of the problems listed
below occurs, take an appropriate measure against them.
Problem Measures
An earth leakage circuit
breaker* that is connected
to the input (primary) side
has tripped.
*With overcurrent protection
1) Decrease the carrier frequency.
2) Make the wires between the inverter and motor shorter.
3) Use an earth leakage circuit breaker with lower sensitivity than the one currently used.
4) Use an earth leakage circuit breaker that features measures against the high frequency
current component (Fuji SG and EG series).
An external thermal relay
was activated. 1) Decrease the carrier frequency.
2) Increase the current setting of the thermal relay.
3) Use the electronic thermal overload protection built in the inverter, instead of the
external thermal relay.
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Selecting inverter capacity
(1) To drive a general-purpose motor, select an inverter according to the nominal applied motor rating listed in the standard
specifications table. When high starting torque is required or quick acceleration or deceleration is required, select an inverter
with one rank higher capacity than the standard.
(2) Special motors may have larger rated current than general-purpose ones. In such a case, select an inverter that meets the
following condition.
Inverter rated current > Motor rated current