Mitsubishi Electric 800 Series Instruction Manual page 450

Electronic bypass sequence function
• When operating the motor at 60 Hz (or 50 Hz), the motor can be more efficiently operated with a commercial power supply.
In addition, if the motor cannot be stopped for a long period of time even for an inverter maintenance and inspection, it is
recommended that a commercial power supply circuit be installed.
• When switching between inverter operation and commercial power supply operation, commercial power supply may be
accidentally applied to the output side of the inverter. To avoid such situation, provide an interlock where the magnetic
contactor at the commercial power supply side turns ON at turn OFF of the magnetic contactor at the inverter output side.
The inverter's electronic bypass sequence that outputs timing signals for the magnetic contactors can act as a complicated
interlock between the commercial power supply operation and the inverter operation.
Connection diagram
• A typical connection diagram of the electronic bypass sequence is shown below.
MC1
MCCB
R/L1
S/L2
T/L3
R1/L11
S1/L21
Inverter start
(forward rotation)
STF
Inverter/bypass
CS
operation interlock
MRS
∗3
External thermal
OH
Reset
RES
SD
10
Frequency
2
setting signal
5
Standard models
MC1
MCCB
External
thermal
Reset
MC2
External
thermal relay
MC3
U
V IM
W
MC1
∗1
MC1
MC2
MC3
∗1
∗2
MC2
24VDC
MC3
MC2
∗1
MC3
SE
Converter unit
R/L1 P/+
S/L2 N/-
Inverter start
T/L3
(forward rotation)
R1/L11
Inverter/bypass
S1/L21
operation interlock
SE
RDA
∗4
ALM
OH
∗4
Y214
RES
RSO
SD
Frequency
setting signal
Separated converter type
(A) Application parameters
MC2
Inverter
MC3
P/+
U
V
N/-
W
STF
CS
∗3
MRS
∗1
SD
MC1
X10
∗3 MC3
∗1
X95
MC2
∗3
X96
RES
MC2
∗1
10
MC3
2
5
SE
R1/L11
S1/L21
PARAMETERS
External
thermal relay
IM
MC1
MC2
∗2
24VDC
MC3
5
GROUP
A
449