What is the longest youd recommend for a cable length from a datalogger to an ECHO sensor?
In manufacturing tests, several of the 15.5 m extension cables sold by ICT International have been connected in lengths up to 78 m with acceptable results. The issue with the length of the cable is most likely resistance. The longer the cable, the more resistance in the wire, which leads to a small signal loss (we saw a 14 mV loss under maximum load over 78 m). If you decide to add your own cable, it must have a braid shield connected to the probe ground to protect it from external noise. We recommend a continuous, 3 conductor, braid-shielded cable for wiring long extensions.