115
4. Parameter description
Parameter
3.
Action which has automatic switching in order (P.249
≠
9999, P.250
≠
9999).
STF
time
A
A
B
C
D
A
A
B
C
D
time
P.249
P.250
MC2
MC1
Setting
frequency
Output
frequency
Actual
motor speed
When automatically switching, A is P.247, B is P.248, C is P.57 and D is P.58.
Note: 1. When the motor is operated at 60Hz (or 50Hz), more efficient operation can be performed by the
commercial power supply than by the inverter. When the motor cannot be stopped for a long time for the
maintenance/inspection of the inverter, it is recommended to provide the commercial power supply circuit.
2. To avoid commercial power supply being applied to the inverter output side when switching between
inverter operation and commercial power supply operation, provide an interlock which the MC of the
commercial power supply side turns on only when the MC of the inverter output side is off. Using the
electronic bypass sequence function that outputs the timing signal for operation of the magnetic contactor,
a complicated commercial power supply switchover interlock can be provided by the inverter.
3. This function is valid in V/F curve. It means P.300 must be set to 0.
4. If P.187=1, P.249 is in the range of 0~600Hz, P.250 is in the range of 0~100Hz.
4.60 Alarm History (P.288~P.291)
P.288 “Alarm code display option”
P.289 “Alarm code”
P.290 “The latest alarm status selection”
P.291 “The latest alarm message”
● The user can read these paragraph parameters to know the frequency, current, voltage and 12 alarm
code which in front of this alarm code when alarm occurred. If execute P.996, this paragraph
parameters will been clear.
