JUKI LK-1900AN Engineer's Manual page 121

Trouble
8. Error E306
Needle thread clamp sensor error
9. Error E730
Main shaft motor encoder error A
LED3 on SDC board: Flashing 3 times
10. Error E731
Main shaft motor encoder error B
LED3 on SDC board: Flashing 4 times
Cause (1)
8-1) Irregular motor rota- 1-A) There are irregularities in the
tions
1-B) Motor leads are broken.
8-2) No sensor signal entry 2-A) The sensor is out of order or
Use of Test Mode
CP-1 or CP-2
2-B) The INT board connector is
2-C) Sensor mounting position is
9-1) Phase A and Phase 1-A) The encoder cord is broken
B signals (main shaft
motor) do not enter.
1-B) There is internal disconnec-
10-1) Position signals U, V, 1-A) The encoder cord is broken
W (main shaft motor)
do not enter.
1-B) There is internal disconnec-
Cause (2)
mechanism, such as over-
loading, etc.
The motor is out of order.
broken.
disconnected.
inadequate.
or out of order.
tion in the SDC board.
or out of order.
tion the SDC board.
Check and corrective measures
Check the mechanism and look for the sec-
tion that is particularly overloaded or whether
screws are loose.
Disconnect CN45 (yellow) of the MAIN board
and check the motor resistance. [See the
Pulse Motor/Solenoid Circuit Diagram.] Re-
place the motor.
Check whether the sensor lamp is turned ON/
OFF when a metallic plate is moved closer
to or separated from the sensor plane. In the
case of no lamp ON/OFF, the sensor is bro-
ken or the connector block is disconnected.
Check the connection of CN65 (yellow) of the
INT board.
Check and correct the sensor mounting posi-
tion.
Confirm whether each signal is delivered
to CN14 of the SDC board. In the case of
encoder error, replace the motor as a whole.
[See the Servo Motor Circuit Diagram.]
Replace the SDC board.
Confirm whether each signal is delivered
to CN14 of the SDC board. In the case of
encoder error, replace the motor as a whole.
[See the Servo Motor Circuit Diagram.]
Replace the SDC board.