Main Circuit Wiring - Saftronics CIMR-VG5U Installation & Quick Start Manual

Main Circuit Wiring

Input Wiring
· Molded-Case Circuit Breaker (MCCB)
Be sure to connect MCCBs or fuses between the AC main circuit power supply and VG5 input
terminals L1, L2 and L3, to protect the input wiring.
· Ground Fault Interrupter
When connecting a ground fault interrupter to input terminals L1, L2 and L3, select one that is not
affected by high frequency.
Examples:
· Magnetic Contactor (MC)
Inverters can be used without an MC installed on the power supply side. When the main circuit
power supply is shut OFF in the sequence, an MC can be used instead of an MCCB. However, when
an MC is switched OFF on the primary side, dynamic braking does not function and the motor coasts
to stop.
The load can be operated/stopped by opening/closing the MC on the primary side. However, fre-
quent switching may cause the inverter to malfunction.
When using a braking resistor unit, use a sequencer to break the power supply side of the inverter in
the event of an overload relay trip contact. If the inverter malfunctions, the braking resistor unit may
be burned out.
· Terminal Block Connection Sequence
Input power supply phases can be connected to any terminal regardless of the order of L1, L2 and L3
on the terminal block.
· AC Reactor
When connecting an inverter (230V/460V/575V, 15kW or less) to a large capacity power supply
transformer (600kVA or more), or when switching a phase-advancing capacitor, excessive peak cur-
rent may flow through the input power supply circuit, which may damage the converter section. In
such cases, install a DC reactor (optional) between inverter 1 and 2 terminals, or an AC reactor
(optional) on the input side. Installation of a reactor is effective for improvement of power factor on
the power supply side.
· Surge Suppressor
For inductive loads (i.e. magnetic contactors, magnetic relays, magnetic valves, solenoids, magnetic
brakes, etc.) connected near the inverter, use a surge suppressor across the coil to minimize the
inductive "kick" when energizing and de-energizing these devices.
Output Wiring
· Motor Connection
Connect motor lead wires to output terminals T1, T2 and T3. Verify that the motor rotates in the for-
ward direction (CCW: counterclockwise when viewed from the motor load side) with the forward
run command. If the motor rotation is incorrect, exchange any two of the motor leads.
· Magnetic Starter
Do not connect a magnetic starter or a magnetic contactor to the output circuit. If the motor load is
connected or disconnected while the inverter is running, the inverter overcurrent protective circuitry
VG5 Installation & Quick-Start Manual
NV series by Mitsubishi Electric Co., Ltd. (manufactured in or after 1988), EGSG
series by Fuji Electric Co., Ltd. (manufactured in or after 1984).
Chapter 1 - Receiving & Installation
Wiring
27