sanyc Posted September 14, 2016 Report Share Posted September 14, 2016 Ok guys, first time attempting ladder programming here using a V130-J-R34. I am using AN0 to get signal from a 3-wire pressure sensor. Brown/Blue goes to +/- 24Vdc and the black wire is my signal. I get a 4-20 mA from the sensor and according to the default jumper settings of the V130 the AN0 is set to accept current as input. I am trying to perform a simple linearization to display how many bars my sensor reads. Since the memory of the analog input is 10-bit this is how I set it up: (see attachment) The logic is that being a 10-bit memory the max 20mA corresponds to DEC 1023 and min 4mA to DEC 204. Then this is converted to 0-10 bars. However it does not work. My MI0 reads always zero and the output MI1 is stuck at -25. Any ideas here about whats wrong? Cheers Quote Link to comment Share on other sites More sharing options...
sanyc Posted September 14, 2016 Author Report Share Posted September 14, 2016 Forgot to attach the rest: Quote Link to comment Share on other sites More sharing options...
Isakovic Posted September 14, 2016 Report Share Posted September 14, 2016 Did you assign MI0 to analog input in hardware configuration? I don't see any other possible mistake in the ladder. It's probably wiring. Could you post a drawing of your wiring? 0 volts from transmitter supply should be connected to PLC input common to get a current loop. 1 Quote Link to comment Share on other sites More sharing options...
MVP 2021 Flex727 Posted September 14, 2016 MVP 2021 Report Share Posted September 14, 2016 This is not a problem with your linearization. Minus 25 is the correct output for an input of 0. If your wiring and other hardware is correct (and you have MI 0 assigned to AN 0) you should always get a minimum value of 204 at MI 0. Quote Link to comment Share on other sites More sharing options...
Kikis Posted September 14, 2016 Report Share Posted September 14, 2016 If you have linked MI0 to AN 0 and your wiring is correct then it should work. Quote Link to comment Share on other sites More sharing options...
MVP 2021 Ausman Posted September 15, 2016 MVP 2021 Report Share Posted September 15, 2016 I agree with Isak and Flex that it simply looks like you haven't assigned the physical input to MI0, or there is a simple wiring issue. I've posted because, just FYI, you might like to look at this post with my calculator. cheers, Aus Quote Link to comment Share on other sites More sharing options...
sanyc Posted September 15, 2016 Author Report Share Posted September 15, 2016 Thank you all for the replies. I had the MI0 link to AN0 in the hardware configuration. The problem turn out to be the pressure sensor I was using. I used another LVDT sensor and it worked great, thanks. Quote Link to comment Share on other sites More sharing options...
MVP 2021 Ausman Posted September 15, 2016 MVP 2021 Report Share Posted September 15, 2016 Thanks for getting back to us all Sanyc with your result. All too often the advice given on the forum is left unanswered. Aus Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.