3-4 meters should be fine.
Longer than that...use shielded wire (or use shielded wire anyway...it can't hurt)
For really long wires you're supposed to use a system called "RS485" (google it)
3-4 meters should be fine.
Longer than that...use shielded wire (or use shielded wire anyway...it can't hurt)
For really long wires you're supposed to use a system called "RS485" (google it)