Omron SYSDRIVE 3G3MV - Installing a Magnetic Contactor

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·For the special-purpose breakerfor Inverters, choose aground fault interrupterwitha
sensitivity amperage of at least 10 mA per Inverter.
·Whenusingageneralleakage breaker, chooseagroundfault interrupterwithasensi-
tivity amperage of 200 mA or more per Inverter and with an operating time of 0.1 s or
more.
D Installing a Magnetic Contactor
If the power supply ofthemaincircuit is to beshut offbecause of the sequence,amag-
netic contactor can be used instead of a molded-case circuit breaker.
When a magnetic contactor is installed on the primary side of the main circuit to stop a
load forcibly, however, the regenerative brakingdoes not work and theload coasts to a
stop.
·A load can be started and stopped by opening and closing the magnetic contactor on
the primary side. Frequently opening and closing the magnetic contactor, however,
may cause the Inverter to break down.
·WhentheInverterisoperatedwiththeDigitalOperator,automaticoperationcannotbe
performed after recovery from a power interruption.
·WhenusingtheBrakingResistorUnit,besuretoarrangeasequenceinwhichthether-
mal relay of the Unit turns the magnetic contactor OFF.
D Connecting Input Power Supply to the Terminal Block
Inputpowersupplycanbe connectedtoanyterminal ontheterminal blockbecausethe
phasesequenceofinputpower supply is irrelevant tothephasesequence(R/L1,S/L2,
and T/L3).
D Installing an AC Reactor
If the Inverter is connected to a large-capacity power transformer (660 kW or more) or
the external phase advance capacitor of the customer is switched, an excessive peak
current may flow through the input power circuit, causing the converter unit to break
down.
To prevent this, install an optional AC reactor on the input side of the Inverter.
This also improves the power factor on the power supply side.
D Installing a Surge Absorber
Always use a surge absorber or diode for the inductive loads near the Inverter. These
inductive loads include magnetic contactors, electromagnetic relays, solenoid valves,
solenoid, and magnetic brakes.
Design Chapter 2