4135

Common Causes

• Failed DD encoder or DD encoder slave sensor on the pertinent axis
• Encoder link cable or connector fault
• Inverter unit control board problem
• Noise on the DD encoder communication link

Troubleshooting Steps

1. 1Read the code number shown with the alarm: code YY=$00 = Error detected at the DD encoder.; code YY=$01 = Error detected at the DD encoder (slave sensor).; code ZZZZ bit13 = Communication error with the DD encoder (slave sensor).; code ZZZZ bit12 = Communication error with the DD encoder.; code ZZZZ bit11 = MT buffer error.; code ZZZZ bit10 = AT mode transmission loop error.; code ZZZZ bit9 = Data over error in the receiving interface.; code ZZZZ bits6-0 = Modulation code, CRC, format, double transmission, double reception, parity, time-out errors.
2. 2Read the code: YY $00 means the error was detected at the DD encoder, $01 at the DD encoder slave sensor; ZZZZ bits identify the fault (bit13 slave sensor comm error, bit12 DD encoder comm error, bit11 MT buffer error, bit10 AT mode transmission loop error, bit9 data over error, bits 6-0 modulation code/CRC/format/double transmission/double reception/parity/time-out).
3. 3Use bit13/bit12 to decide whether to inspect the slave sensor or the main DD encoder, then check that device's cable and connector for damage, oil or bent pins.
4. 4Check encoder link cable routing for noise exposure and keep it separated from motor power cables with shields grounded.
5. 5Swap the encoder link cable with a known-good cable and cycle power to see whether the same bits return.
6. 6If errors persist, replace the DD encoder (or slave sensor) on the pertinent axis; if still unresolved, have the inverter unit control board checked, then re-home the axis.