Mitsubishi Electric FR-A740-00023 Instruction Manual page 211

(6) DC feeding mode 2 (Pr. 30 = "20, 21")
⋅ When "20 or 21" is set in Pr. 30, operation is performed with AC power normally and with DC power such as battery
at power failure.
⋅ Connect the AC power supply to terminal R/L1, S/L2, and T/L3 and connect the DC power supply to terminal P/+
and N/-. Also, remove jumpers across terminal R/L1-R1/L11 and S/L2-S1/L21, and connect terminals R1/L11 and
S1/L21 to terminal P/+ and N/-.
⋅ Turning on the DC feeding operation permission signal (X70) enables DC power supply operation. Refer to the
table below for I/O signals.
Signal Name
DC feeding operation
X70
permission signal
Input
X71 DC feeding cancel signal
Output Y85 DC feeding signal
⋅ The following shows the connection diagram when switching to a DC power using inverter power failure detection.
DC feeding permission signal
DC feeding cancel signal
Frequency command
Frequency setting
potentiometer
*1 Assign the function using Pr. 178 to Pr. 189 (input terminal function selection).
*2 Assign the function using Pr. 190 to Pr. 196 (output terminal function selection).
When performing operation with DC feeding, turn
on the X70 signal.
When the inverter output is shut off because of
power failure, the inverter can be started in about
150ms after switching off the X70 signal then on
again. (When automatic restart operation is valid,
the inverter starts after additional Pr. 57 set time
has elapsed.)
When the X70 signal turns off during inverter
operation, output is shutoff (Pr .261 = 0) or the
inverter is decelerated to a stop (Pr. 261 ≠ 0).
Turn this signal on to stop DC feeding.
When the X71 signal is turned on during inverter
operation with turning on the X70 signal, output is
shutoff (Pr. 261 = 0) or the inverter is decelerated
to a stop (Pr. 261 ≠ 0), then the X85 signal turns
off after the inverter stop.
After turning on of the X71 signal, operation can
not be performed even if the X70 signal is turned
on.
This signal turns on during power failure or under
voltage of AC power.
The signal turns off when the X71 signal turns on
or power is restored.
The Y85 signal does not turn off during inverter
operation even if the power is restored and turns
off after an inverter stop.
When the Y85 signal turns on because of
undervoltage, the Y85 signal does not turn off
even if undervoltage is eliminated.
ON/OFF status is retained at an inverter reset.
MCCB
Three-phase AC
power supply
DC power
MC
(+)
(-)
Forward rotation start
Reverse rotation start
Contact input common
3
2
1
1/2W1kΩ
Motor brake and stop operation
Description
Inverter
Inrush
U
R/L1 current
limit circuit
S/L2 V
W
T/L3
R1/L11
S1/L21
(Ground)
P/+
N/-
STF
STR
*1
X70
*1
X71
DC feeding signal
*2
Y85
PC
10
SE
2
5
Parameter Setting
Set 70 in any of Pr. 178 to Pr. 189.
Set 71 in any of Pr. 178 to Pr. 189.
Set "85 (positive logic) or 185
(negative logic)" in any of Pr. 190
to Pr. 196
IM
Earth
MC
24VDC
4
201