Cause : Encoder fault comes when the encoder cable is in open circuit, short circuit or poor contact. This fault "Err20" comes when encoder parameter incorrect or faulty encoder cable.

1. Encoder is not matched.
2. Set the type of encoder correctly.
3. Encoder wiring is incorrect.
4. Check the PG card power supply and phase sequence.
5. Encoder is damaged.
6. Replace encoder
7. PG card is abnormal.
8. Replace PG card.