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newbie in need of help!

Posted: Fri Feb 13, 2015 1:19 pm
by mk2harrier
hello,
as you can probably guess by now i am new to the site.

just to give you some background, i am a mechanical electrical engineer on the railway, operating and maintaining on track machines.

i am really hopefull that somebody here can help me out. the machines i work on use Potentiometers on just about everything, the voltage from these pots go through a PLC and numerous other circuitry and is then converted to a distance in millimetres and displayed.

the problem i have is during a working shift when everything is time critical, sometimes one of these pots decides to give up, changing one is pretty straight forward but setting up requires upto 3 people, one to adjust, one to read the display, and one to act as a relay between the two.

what i would like to do is make a test box that can be plugged into the pot cables and take a reading thus making it a one man job and much quicker.

the test box would need to convert a voltage and display the distance in MM/CM. i can find simple kits to make voltmeters etc but would anybody know of a kit that would serve this purpose or multiple kits to achieve my goal?

i know its a big ask, especially from a newbie but any help would be much appreciated.

many thanks
Simon

Re: newbie in need of help!

Posted: Sun Feb 15, 2015 5:01 pm
by Pauldf
Are they potentiometers as in they change resistance with a wiper arm?
I'd have thought if they are talking to a PLC they'd use encoders which are basically a round disc with a pattern inside an enclosure which spins with LED emmitters and recievers watching the pattern, similar to what you get in a roller ball computer mouse.