Main circuit terminal specifications
2.2 Main circuit terminal specifications
Specification of main circuit terminal
AC power input
U, V, W
Power supply for
(22K or lower)
Built-in brake circuit
· When connecting a dedicated brake resistor (FR-ABR) and brake unit (FR-BU2, FR-BU, BU) remove jumpers across terminals
PR-PX (7.5K or lower). For details, refer to page 40.
Terminal arrangement of the main circuit terminal, power supply and the motor
R/L1 S/L2 T/L3
Connect to the commercial power supply.
Keep these terminals open when using the high power factor converter (FR-
HC and MT-HC) or power regeneration common converter (FR-CV).
Connect a three-phase squirrel-cage motor.
Connected to the AC power supply terminals R/L1 and S/L2. To retain the
fault display and fault output or when using the high power factor converter
(FR-HC and MT-HC) or power regeneration common converter (FR-CV),
remove the jumpers from terminals R/L1-R1/L11 and S/L2-S1/L21 and apply
external power to these terminals.
The power capacity necessary when separate power is supplied from R1/
L11 and S1/L21 differs according to the inverter capacity.
Remove the jumper from terminals PR-PX (7.5K or lower) and connect an
optional brake resistor (FR-ABR) across terminals P/+-PR.
For the 22K or lower, connecting the resistor further provides regenerative
Connect the brake unit (FR-BU2, FR-BU, BU and MT-BU5), power
regeneration common converter (FR-CV), power regeneration converter
(MT-RC), high power factor converter (FR-HC and MT-HC) or DC power
supply (under the DC feeding mode).
For the 55K or lower, remove the jumper across terminals P/+ - P1 and
connect the DC reactor. (As a DC reactor is supplied with the 75K or higher
as standard, be sure to connect the DC reactor.)
Keep the jumper across P/+ and P1 attached when a DC reactor is not
When the jumper is connected across terminals PX-PR (initial status), the
built-in brake circuit is valid. (Provided for the 7.5K or lower.)
For earthing (grounding) the inverter chassis. Must be earthed (grounded).
11K or lower
FR-A720-1.5K to 3.7K
FR-A740-0.4K to 3.7K
R/L1 S/L2 T/L3
18.5K or higher