4139

Common Causes

• Faulty DD encoder (slave sensor)
• Damaged or loose encoder link cable or connector
• Abnormal voltage at the encoder fuse (outside 10.6-13.8 V)
• Incompatible encoder parameters or communication protocol version
• Faulty inverter unit control board

Troubleshooting Steps

1. 1Read the code number shown with the alarm: code XX=0 = Failure during reset step; code XX=1 = Failure during network address setting; code XX=2 = Failure requesting basic communication information; code XX=3 = Failure during communication software version change; code XX=4 = Failure acquiring device information; code XX=5 = Failure during parameter change; code XX=6 = Failure at position detection start; code XX=7 = Failure at AT mode start
2. 2Record the full code XXYYZZZZ. XX shows which initialization step failed (0=reset through 7=AT mode start) and YY shows the failure type (communication error, timeout, bad response, or parameter error).
3. 3If XXYY shows $FFFF, the ZZZZ value is the measured encoder fuse voltage; check that the encoder supply is within the normal 10.6-13.8 V range and investigate the power supply if it is not.
4. 4If YY=6, the ZZZZ value identifies the parameter problem, such as multi-turn detection range over or an incompatible protocol or data format; verify the encoder configuration matches the control.
5. 5If YY=5, decode ZZZZ using MCS DD Encoder error alarm 1136 for the detailed encoder alarm code.
6. 6Inspect the encoder link cables and connectors between the slave sensor and the inverter unit for damage, poor seating, or contamination; reseat and retest.
7. 7If wiring and supply voltage are good, replace the DD encoder (slave sensor); if the fault persists, suspect the inverter unit control board and contact Okuma service.