2.10.2 Connection of the brake unit (FR-BU2)
Connect the brake unit (FR-BU2(H)) as follows to improve the braking capability during deceleration.
Connection example with the GRZG type discharging resistor
When wiring, make sure to match the terminal symbols (P/+, N/-) on the inverter and on the brake unit (FR-BU2). (Incorrect connection will
damage the inverter and brake unit.)
When the power supply is 400 V class, install a stepdown transformer.
Be sure to remove the jumper across terminals PR and PX when using the FR-BU2 with the inverter of FR-A820-00490(7.5K) or lower, or FR-
A840-00250(7.5K) or lower.
The wiring distance between the inverter, brake unit (FR-BU2) and discharging resistor must be within 5 m. Even when the cable is twisted, the
wiring length must be within 10 m.
It is recommended to install an external thermal relay to prevent overheat of the discharging resistor.
For the connection method of the discharging resistor, refer to the Instruction Manual of the FR-BU2.
• Recommended external thermal relay
• Set "1" in Pr.0 Brake mode selection in the FR-BU2 to use a GRZG type discharging resistor.
• Do not remove the jumper across terminals P/+ and P1 except when connecting a DC reactor (FR-HEL).
2. INSTALLATION AND WIRING
2.10 Connection of stand-alone option units
GZG 300W-50Ω (one)
GRZG 200-10Ω (three in series)
GRZG 300-5Ω (four in series)
GRZG 400-2Ω (six in series)
GRZG 200-10Ω (six in series)
GRZG 300-5Ω (eight in series)
GRZG 400-2Ω (twelve in series)
10 m or less
To a resistor
To the brake
unit terminal P/+