3139

Common Causes

• Faulty DD encoder (slave sensor) itself
• Damaged or loose encoder link cable or connector between the encoder and the inverter unit
• Defective inverter unit control board
• Encoder fuse voltage outside the normal 10.6-13.8 V range (code XXYY=$FFFF)
• Incompatible or corrupted encoder communication parameters (YY=6)

Troubleshooting Steps

1. 1Read the code number shown with the alarm: code XX=0 = Error detected during reset step of link initialization; code XX=1 = Error during network address setting; code XX=2 = Error while requesting basic communication information; code XX=3 = Error during communication software version change; code XX=4 = Error while acquiring device information; code XX=5 = Error during parameter change; code XX=6 = Error at position detection start; code XX=7 = Error at AT mode start
2. 2Read the code on screen. If XXYY shows $FFFF, the ZZZZ value is the measured encoder fuse voltage ($9980 = 12 V); check the encoder power supply and fuse before anything else.
3. 3Note XX (the sequence step where startup stopped) and YY (error type). YY=0 means a link communication error, YY=1/2/3 means a transmit/receive timeout, YY=4/5 means a bad response from the device, YY=6 means a parameter problem.
4. 4Power down and lock out. Inspect and reseat the encoder link cable connectors at both the DD slave encoder and the inverter unit; look for bent pins, oil contamination, or a chafed cable.
5. 5If YY=6, the ZZZZ value identifies the parameter fault (e.g. 3 = multi-turn detection range over, 2/4/5/6 = incompatible communication format); have the encoder parameter set verified against the machine specification.
6. 6If the cable and connectors are good and the fault persists at the same sequence step, replace the DD encoder (slave sensor).
7. 7If a new encoder does not clear it, the inverter unit control board is the remaining suspect; record the full XXYYZZZZ code and contact Okuma service.