Analog DeviceNET Flex IO Module Problem

Hi all,

I have a 1756 DNB Device net controller with a 1794-ADN DeviceNET Flex IO adapter with 2 1794 - 12 Channel Analog Input cards fitted. The second card is not used. The first 8 inputs of the first card are set to Voltage inputs and the last 4 set to current.

All the voltage ones work as intended. The values are read in ok to the PLC. I get no response on the analog inputs. Both the origianal source has been tested and An analog signal has been placed directly onto the inputs. Pretty sure it is in the configuration. This is a repeat machine and it has worked on the previous set up. The device net networx .dint files from the last machine were used on this one also.

Any ideas, into day 2 of battle now!

J

Explain exactly what you mean about the last four channels being set for 'Analog'. Do you mean 'Current' ?

If the same *.DNT files were used, then the configuration for the analog modules is the same.

It's possible that the configuration wasn't successfully applied, or that you have modified it from the original settings. At that point, unless you retained a known-good copy of the *.DNT file, you cannot be certain that the configuration is the same as the previous machine.

I recommend starting from the beginning: post a wiring diagram and a *.DNT file and folks can help you see if there are conflicts between them.

Hey Ken,

Yes, I meant current, sorry, head is getting fried from this!

The original dint file was created on a different laptop and is now being applied from mine so is it possible it loads up different? I know originally I had an older version of networx but have since upgraded it to the same version as was orginally used to configure the file. (11)
I know there was problems configuring this card in the original machine also but no one remembers the fix. It is possible that the original file I had wasnt the working file.
I go online and upload the configuration for the 1794-ADN. The saved file doesnt "hold" the module configuation so I change that so the first 8 are Voltage and the last 4 current (4-20mA). Before I upload the new config I remove the device from the scanlist and cycle the power as per a previous bit of advice I saw from you on this forum.

I have attached a screenshot of what I'm working on, the original dint file and an overview of how im simulating the current- feeding in around 8mA according to the meter.

Cheers
J

Hi

I looked at you settings in the flex module of the d net file you have posted and the cards are not setup. You need to drill down into the flex module and then select the card. You will then see a tab called Flex Configuration settings and this is where you set up each channel settings. You may have to cycle the power after you change these but I am not sure. Sometimes I have had to clear the flex module under the transactions tab before I could get a 8 channel card to change its settings.

I also sent you a privite message and this may also help.

Donnchadh

Hi, Thanks for the reply.

In the saved copy it doesnt hold these settings for some reason. But I change them in the online version.I know they hold because originally I had no readings on the voltage. I removed the device from the scan list, cycled power to the module, changed the settings as you described then re added to the scan list. I then had voltage values on inputs 1-8 but still no update on my analog input.

Hi J

did you Clear the memory on the flex module after you removed it from the scan list, I say this because a while back I was changing the settings on a 8 channel card and this was the only way I coould get it to save the settings.
Also when you upload from the unit does it show the settings you have sent down to it.

Donnchadh

Hi J

Just also noticed that you second card on the file you posted is set up for 4 output bytes as the first card which is the same is set up for 2 bytes. No to sure how or why you did this or even if it makes a differance.

Donnchadh

It was that way before and because it isn't been used here I left as was. Trying to change as little as possible and because it was the card after this one, didn't think it would affect the data on the first one.

As you suggested I reset the module under the transaction tab. I then checked my online values to verify that i wiped it and yes, my voltage values were not being read in. I then offline, changed the first 8 to voltage and last 4 to current, removed from scan list, reset module and re-uploaded. My voltage values returned but still nothing in the analog values.

I'm missing the point here somewhere serious! :/

Hi J

Ok lets take a step back.
What is your meter reading that you have in your drawing.
Are you stting it up as 0 to 20 or 4 to 20 ma.
When you say you are getting no reading does this mean 0 value.
Could you set one up as a voltage and see could you then use your voltage source to see if this works.

Donnchadh

I have it set up to 0-20mA. Meter reads approx 8mA.

I get 0mA on the monitor screen of the properties. and no change on the input map in the plc program. (Reads:32767) On my voltage inputs they read the same value when open circuited

I'm after noticing that the last machine's flex module was a "1794-ADN/B" on this machine the module is "1794-ADN/C". When I changed it by forcing it to re register the eds file for C I thought i was getting places. Then, I lost both voltage and current. Reverting back to the original set up I got voltage back.

Going to try that again maybe (clean run at it) and also, try reading a voltage instead to see how i get on.

Cheers
J

hi

I have 1769 l30 er processor and my i am using flex IO on device net configuration is as follows

1769-sdn
1794-adn
1794-ib16
1794-ie12
1794-ie12

here i am getting my digital input in my logic via device net but my analog inputs are not comming please if any body is ther e help me