Mitsubishi Electric FR-E740 SC EC Series User Manual

Troubleshooting Check first when you have troubles
FR-E700SC EC 7 - 25
7.6.4 Motor generates heat abnormally
7.6.5 Motor rotates in opposite direction
7.6.6 Speed greatly differs from the setting
Check Points Possible Cause Countermeasures
Refer to
Page
Motor
Motor fan is not working
(Dust is accumulated.)
Clean the motor fan.
Improve the environment.
—
Phase to phase insulation of the motor is
insufficient.
Check the insulation of the motor.
—
Main circuit
The inverter output voltage (U, V, W) are
unbalanced.
Check the output voltage of the inverter.
Check the insulation of the motor.
8-2
Parameter
setting
The Pr. 71 "Applied motor" setting is wrong. Check the Pr. 71 "Applied motor" setting.
6-85
— Motor current is large. Refer to "7.6.11 Motor current is too large"
7-29
Check Points Possible Cause Countermeasures
Refer to
Page
Main circuit
Phase sequence of output terminals U, V and
W is incorrect.
Connect phase sequence of the output cab-
les (terminal U, V, W) to the motor correctly
3-6
Input signal
The start signals (forward rotation, reverse
rotation) are connected improperly.
Check the wiring. (STF: forward rotation, STR:
reverse rotation)
3-14
Adjustment by the output frequency is
improper during the reversible operation
with Pr. 73 "Analog input selection" setting.
Check the setting of Pr. 125, Pr. 126, C2 to C7.
6-85
Parameter
setting
Pr. 40 "RUN key rotation direction selection"
setting is incorrect.
Check the Pr. 40 setting.
6-313
Check Points Possible Cause Countermeasures
Refer to
Page
Input signal
Frequency setting signal is incorrectly input. Measure the input signal level.
—
The input signal lines are affected by external
EMI.
Take countermeasures against EMI such as
using shielded wires for input signal lines.
3-47
Parameter
setting
Pr. 1, Pr. 2, Pr. 18, calibration parameter C2 to
C7 settings are improper.
Check the settings of Pr. 1 "Maximum fre-
quency", Pr. 2 "Minimum frequency", Pr. 18
"High speed maximum frequency".
6-50
Check the calibration parameter C2 to C7 set-
tings.
6-181
Pr. 31 to Pr. 36 "Frequency jump" settings are
improper.
Narrow down the range of frequency jump.
6-52
Load
Stall prevention is activated due to a heavy
load.
Reduce the load weight.
—
Parameter
setting
Set Pr. 22 "Stall prevention operation level
"higher according to the load. (Setting Pr. 22
too large may result in frequent overcurrent
trip (E.OC).)
6-42
Motor
Check the capacities of the inverter and the
motor.
—

Mitsubishi Electric FR-E740 SC EC Series Specifications

General

Brand	Mitsubishi Electric
Model	FR-E740 SC EC Series
Category	Inverter
Language	English