What is the RM08 max wires length?

The RM08 encoder max wires length is 0.5m.

There are two main reasons for limited length:
1. product reliability due to long thin wires instead of shielded cable
2. assembling process – handling with long wires during the curing process
For longer distance, the thicker and shielded extension cable is recommended. Example of RM08 with extended cable:

Depending on environmental conditions, also a line driver for digital outputs needs to be considered.