Mitsubishi Electric FR-F740 EC Instruction Manual page 531

Parameter
● Operation sequence example when there is automatic switchover sequence
(Pr. 139 ≠ 9999, Pr. 159 ≠ 9999)
Output frequency
Frequency command
Actual motor
Inverter operation
Commercial power
supply operation
Fig. 6-211: Signal timing when there is automatic switchover sequence
Operation procedure
Turn the power supply on.
Set the parameters.
Pr. 135 = 1 (Commercial power supply operation enabled.)
Pr. 136 = 2.0s
Pr. 137 = 1.0s (Set the time longer than the time from when MC3 actually turns on until the
inverter and motor are connected. If the time is short, a restart may not function properly.)
Pr. 57 = 0.5s
Pr. 58 = 0.5s (Be sure to set this parameter when commercial power supply operation is
switched to inverter operation.)
Start inverter operation.
The switchover to commercial power supply operation is performed by a command or when
the switchover frequency is reached.
When the Stop command is applied the system switches to inverter operation and the motor
is decelerated under control.
FR-F700 EC
STF
speed
MC3
MC2
A: Pr. 136: MC switchover interlock time
B: Pr. 137: Start waiting time
C: Pr. 57: Restart coasting time
D: Pr. 58: Restart cushion time
Special operation
Time
Time
I001241E
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