Mitsubishi Electric FR-A820-00046 (0.4K) Instruction Manual page 537

• Example of operation sequence with automatic bypass sequence (Pr.139 ≠ "9999", Pr.159 ≠ "9999")
ON
STF
OFF
Output frequency Pr.139
Frequency command
Actual motor speed
INV
ON
MC3
operation
OFF
Commercial
ON
MC2
power supply
OFF
operation
A : Pr.136 MC switchover interlock time
C : Pr.57 Restart coasting time
Operating procedure
• Operation flowchart
Power supply ON
Setting the parameters
Start inverter operation
Constant-speed commercial
power supply operation
Deceleration (stop)
inverter operation
• Signal operation after setting parameters
Status
Power ON
At start
(inverter)
During constant-speed
operation
(commercial power supply)
For deceleration,
switched to the inverter
operation (inverter)
Stop
536
5. PARAMETERS
5.14 (A) Application parameters
C A A
B : Pr.137 Start waiting time
D : Pr.58 Restart cushion time
• Pr.135 = "1" (open collector output terminal of inverter)
• Pr.136 = 2.0 s
• Pr.137 = 1.0 s (Set the time until MC3 is actually turned ON and the inverter and motor
are electrically connected. If the time is short, the restart may not function properly.)
• Pr.57 = 0.5 s
• Pr.58 = 0.5 s (Always set this to switchover from the commercial power supply operation
to the inverter operation.)
MRS CS STF
OFF OFF OFF
(OFF) (OFF) (OFF)
OFF→ON OFF→ON OFF→ON ON
ON ON→OFF ON
ON OFF→ON ON
ON ON ON→OFF ON
Pr.159
B C D A
MC1 MC2
OFF→ON OFF
(OFF→ON) (OFF)
OFF
ON OFF→ON ON→OFF
ON ON→OFF OFF→ON
OFF
A B C D
MC3 Remarks
OFF→ON External operation mode
(OFF→ON) (PU operation mode)
ON
MC2 turns ON after MC3 turns OFF.
Waiting time is 2 s (while coasting).
MC3 turns ON after MC2 turns OFF.
Waiting time is 4 s (while coasting).
ON
Time
Time