Special Operation And Frequency Control; Bypass-Inverter Switchover Function (Pr. 57, Pr. 58, Pr. 135 To Pr. 139, Pr. 159) - Mitsubishi FR-F720-00046-NA Instruction Manual

Special operation and frequency control

4.21 Special operation and frequency control

Purpose
Switch between the inverter operation and
bypass operation to operate.
Avoid overvoltage alarm due to regeneration by
automatic adjustment of output frequency

4.21.1 Bypass-inverter switchover function (Pr. 57, Pr. 58, Pr. 135 to Pr. 139, Pr. 159)

The complicated sequence circuit for bypass operation is built in the inverter. Hence, merely inputting the start,
stop or automatic switchover selection signal facilitates the interlock operation of the switchover magnetic
contactor.
Parameter
Name
Number
57 Restart coasting time
58 Restart cushion time
Electronic bypass sequence
135
selection
136 MC switchover interlock time
137 Start waiting time
138 Bypass selection at a fault
Automatic switchover
139 frequency from inverter to
bypass operation
Automatic switchover
159 frequency range from bypass
to inverter operation
The above parameters can be set when Pr. 160 User group read selection = "0". (Refer to page 192.)
294
Parameter that must be Set
Bypass-inverter switchover
function
Regeneration avoidance
function
Setting Range
Initial
200V class
Value
(400V class)
⋅ FR-F720-00077 (FR-F740-00038) or lower .......... 0.5s,
⋅ FR-F720-00105 to 00340
(FR-F740-00052 to 00170) ................................... 1s,
⋅ FR-F720-00490 to 02330
0
(FR-F740-00250 to 01160).................................... 3.0s,
⋅ FR-F720-03160 (FR-F740-01800) or higher......... 5.0s,
The above times are coasting time.
9999
02330
0.1 to
(01160)
5s
or lower
Set the waiting time for inverter-triggered restart after an
03160
instantaneous power failure.
(01800) 0.1 to
or 30s
higher
9999 No restart
1s 0 to 60s Set a voltage starting time at restart.
0 Without electronic bypass sequence
0
1 With electronic bypass sequence
1s 0 to 100s Set the operation interlock time of MC2 and MC3.
Set the time slightly longer (0.3 to 0.5s or so) than the time
0.5s 0 to 100s
from when the ON signal enters MC3 until it actually turns ON.
0 Inverter output is stopped (motor coast) at inverter fault.
Operation is automatically switched to bypass operation at
0
1 inverter fault (Not switched when an external thermal relay
operation (E.OHT) or CPU fault (E.CPU) occurs).
Set the frequency to switch inverter operation to bypass
operation.
Inverter operation is performed from a start until Pr. 139 is
0 to 60Hz
reached, and when the output frequency is at or above Pr.
9999
139, inverter operation is automatically switched to bypass
operation.
9999 Without automatic switchover
Valid during automatic switchover operation (Pr. 139 ≠ 9999)
When the frequency command decreases below (Pr. 139 - Pr.
159) after operation is switched from inverter operation to
bypass operation, the inverter automatically switches
0 to 10Hz
operation to inverter operation and operates at the frequency
of frequency command. When the inverter start command
(STF/STR) is turned OFF, operation is switched to inverter
9999
operation also.
Valid during automatic switchover operation (Pr. 139 ≠ 9999)
When the inverter start command (STF/STR) is turned OFF
9999 after operation is switched from inverter operation to bypass
operation, operation is switched to inverter operation and the
motor decelerates to stop.
Pr. 57, Pr.58, Pr. 135 to Pr. 139,
Pr. 159
Pr. 665, Pr. 882 to Pr. 886
Description
Refer
to Page
294
299