Velpandian P

1769-IF8 module doesn't read my analog input

6 posts in this topic

Hi, 
We are working with AB-CompactLogix L32E controller including Compact I/O 1769-IF8 analog input module. We have been configure 1769-IF8 module as engineering units (Min 4000 to Max 20000).

At the analog input side we have connected Non-Loop powered 4-20mA Amplifier as per 1769-IF8 wiring drawing (Iout+ to Iin+ and Iout- to V/I in-). The amplifier successfully generate the 4-20mA signal without oscillation at the output terminal. But the controller shows only 3200 (engineering unit) value with no change.  

We don't know what's the problem is. Also we had double check our input wiring connection and module configuration there is nothing wrong. Apart from that please give us solution to eradicate this problem and give any suggestion.

Edited by Velpandian P

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What version of software are you using?  When using configuration of Engineering Units the range is 3,200 to 21,000 for 4-20mA.  Is the channel enabled? Are the alarms disabled? If the alarms are enabled that could limit your channel.

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we are using RSLogix 5000 v19.01.00 software. And i couldn't understand your question in the above comment which are "Are the alarms disabled? If the alarms are enabled that could limit your channel".

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Under the configuration of the Card see the attached two screen shots. Typically the alarms are disabled by default. 

Did you try any of the other scaling methods and change the signal generator to see if the value changes.

If you are getting a reading of 3,200 and it is not changing that would tell me the card is seeing 4mA

Pic 1.jpg

Pic 2.jpg

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28 minutes ago, brewer said:

Thank Under the configuration of the Card see the attached two screen shots. Typically the alarms are disabled by default. 

Did you try any of the other scaling methods and change the signal generator to see if the value changes.

If you are getting a reading of 3,200 and it is not changing that would tell me the card is seeing 4mA

Pic 1.jpg

Pic 2.jpg

Thank you brewer, it may be useful.

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Tie I in+ to V in+

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