Basit (Customer) asked a question.
Hello,
Am trying to create a tester box using a click PLC to determine pass or fail; as part of the test i will be testing a resistance of about 70 - 75 ohms.
Am trying to create a tester box using a click PLC to determine pass or fail; as part of the test i will be testing a resistance of about 70 - 75 ohms.
My question is that, is there a cheap ohm meter that I can add to the enclosure instead of using a multi meter? second question, can someone advise me on how to send the ohms value to the PLC to determine a pass or fail if the value is in or outside the acceptable ranges. Note: I do not want to send any voltage to the device, just want to get the ohms value and then use it.
Thank you
I have tested resistance and you'll need a signal conditioner, like the SCU-1400. Have its analog output to the analog input of the Click. You'll create the signal range in the Click software and some PLC code for pass/fail.
Thank you for helping. ill review the SCU-1400 and see if it would be a good fit for my application.
Are accuracy and repeatability important?
Thank you for willing to help, repeatability is important as the device will be used for testing connector cables. accuracy with + or - 3ohms would be good.
How long are your cables (2-wire or 4-wire,) what switching devices, what means of electrical connection between wiring and DUT (alligator/pogo/spring-loaded pins...?)
Does this test require any traceability/calibration/documentation.
We do not know any requirements -- other than a resistance test and pass/fail/Ω value.
Another way that you might be able to do this is with just a analog voltage input module and no ohm meter being converted. Voltage will drop over a specific resistance, so if you were to feed a nice stable 10v DC through your conductor in the cable, you should be able to do some math in the PLC to determine how much voltage has dropped and thus determine the cable resistance. If resistance is out of spec, the voltage drop will be different than with a good cable. You will want to use a 16-bit analog voltage input card if you do this so that you can measure very small voltage changes. You will also probably want a nice and stable power supply with as little ripple as you can, and you will want to use a pretty long smoothing filter in the PLC to keep the signal stable.