Hello all. I have an IOM142A board from phanderson.com that I have been using for a couple of years now. I put temperature sensors in every room of the house, as well as the garage and basement. Overall it works pretty well except that I am getting a lot of read errors on certain temperature sensors.
I have three wire runs. The first run is connected to the first input on the IOM142A and has six sensors. It is a single line and ends in the attic with a single temperature sensor on the very end of the line. The second and third runs consist of a single sensor at the end of each and are connected to the second output on the IOM142A. However, I was forced to use a star configuration on these last two.
My problem is that the sensors on the end of each wire run have a lot of read errors. Occasionally some middle sensor will log a lot of errors, but generally they go weeks without a single error but the end sensors log hundres of errors in that time (my software issues a read every 15 minutes).
All the wire is CAT5E. The sensors are soldered to a three inch piece of CAT5E which is crimped to a modular plug with gold contacts. The total length of the run with six sensors is less than 100 feet. The two runs in the star configuration are approximately 15 feet and 35 feet respectively.
It's strange to me that it's only the end sensors that have problems. Should I be using some type of terminating resistor at the end of the line? Any suggestions?
Thanks. Bill