How to choose a Hall Effect Speed Sensor

by: Pierre Grimes

I have been a distributor for AI-Tek Speed Sensors for over 40 years. On several occasions I have been asked what is the difference between a TTL output and a Supply Tracking output. This is a very good question and I will try to post a straight forward, easy to understand what's going on without having to be an electronics's guru. The speed sensors I sold can be found at www.autoctrls.com .

Basically if the distance between the hall effect sensor and the receiving tachometer is less than 200 feet, a TTL output should work very well. But if the distance is approaching 1000 feet or more, it might be a good idea to use supply tracking to take into account line losses which could weaken the signal at the receiving instrument or tachometer. The receiving instrument could be an input to a PLC. Always check in the input specifications on the instrument (Tachometer) that will process or display the RPM or Count from a Hall Effect Sensor. Take a look at the hall effect sensors available from Automatic Controls .