Maximum cable length

  • Hey guys, I was wondering what is the maximum length of a shielded cable I can put between Arduino and the sensors?

  • Hero Member

    @mk55 The length of the cable will very much depend on the type of signal transmitted. i.e. analog/ digital ; frequency ; level ; low/high impedance of signal source and the type of cable used. Can you tell what type of sensor you are planning to connect?

  • Thanks for your reply.
    I'm planning to connect the cable to a machine that has a 5 digital on/off sensors.
    When the digital sensors is closed I can read 3v.
    I'm planning using this cable:
    The cable will also provide power(12v) to the Arduino

  • Hero Member

    @mk55 A Cat5 (LAN) cable can run up to 100m with a 1Gbit datarate (with twisted wire pairs). You will never get these datarates with Arduino. From simple judgement (simple on/off) the cable length would be limited mostly by internal resitance and power dissipation.

    eg. with this cable (22AWG) a cable length of 100 meter and a 100mA current, the voltage drop would be around 1 V per wire. (so still 10 V left to power your Arduino).
    btw. 12V is the max for a good quality Arduino, many clones will reach their end of life very soon with 12V.