Mitsubishi Electric FR-A700 Instruction Manual page 276

Speed control by real sensorless vector control, vector control
Troubleshooting
Phenomenon
Motor does not rotate.
1
(Vector control)
Tab. 6-16: Troubleshooting (1)
6 - 96
Cause
(1) The motor wiring is wrong
(2) Encoder specifications
(encoder specification selec-
tion switch FR-A7AP) are
wrong
(3) The encoder wiring is wrong.
(4) The Pr. 369 "Number of
encoder pulses" setting and
the number of encoder used
are different.
(5) Encoder power specifications
are wrong. Or, power is not
input.
Countermeasures
(1) Wiring check
Select V/f control (Pr. 800 = 20) and check
the rotation direction of the motor.
Check the speed monitor output from out-
put terminal CA.
For the FR-V5RU, set "340V" for 3.7kW or
less and "320V " for more in Pr. 19 "Base
frequency voltage", and set "50Hz" in Pr. 3
"Base frequency".
When the forward rotation sig-
nal is input, the motor running
in the clockwise direction as
viewed from the motor shaft is
normal. (If it runs in the clock-
wise direction, the phase
sequence of the inverter sec-
ondary side wiring is incor-
rect.)
(2) Check the encoder specifications. Check
the encoder specifications selection switch
(FR-A7AP) of differential/complimentary.
(3) Check that FWD is displayed when running
the motor in the clockwise direction from
outside during a stop of the inverter with
vector control setting.
If REV is displayed, the encoder phase
sequence is wrong.
Perform the correct wiring or match the
Pr. 359 "Encoder rotation direction"..
Relationship between the
Pr. 359
motor and encoder
0
Encoder
Clockwise direction as viewed from
A is forward rotation
1
Encoder
(Initial
value)
Counter clockwise direction as
viewed from A is forward rotation
(4) The motor will not run if the parameter set-
ting is smaller than the number of encoder
pulses used. Set the Pr. 369 "Number of
encoder pulses" correctly.
(5) Check the power specifications (5V/12V/
15V/24V) of encoder and input the external
power supply.
Parameter