Cannot get 1746-N18 Analog Input card to read inputs on last 4 inputs (4-7)

ggreier

Member
Join Date
Nov 2017
Location
Ontario
Posts
3
Hi everybody
Does anybody have experience with the Analog input card 1746-N18?
Cannot get the last 4 inputs (4-7) to work like the first 4 (0-3) inputs. They are set to input type 4-20ma using 1746-N14 data format. First 4 inputs work perfectly but nothing on the last 4. The AB manual says that I need to configure the input types to +-20ma (page C3) and this doesn't even work either. Could the card be bad? I need to use the 4-20ma option for all 8 inputs. On the last 4 inputs, if I don't enter 110 in the output table for this card, the representing input lights flash on the card. Any ideas?
 
Probably a dumb suggestion but are the minus (-) terminals on all inputs connected back to the power source?
 
Yes
All the minus terminals are jumpered together to the Negative terminal of the 24vdc power source and the Positive terminal of the power source is connected to the transmitter +. The transmitter - is then connected to the Positive terminal of the N18 card.
I took a Fluke Calibrator and injected a 12 ma source to each of the last 4 inputs and got mixed to no results.
Had all inputs set to 4-20ma with 1746-N14 format.
On input 4, I got 3277 (decimal) reading which is 0 ma
input 5, 0, meaning open circuit
input 6, 3277 again
input 7, I got 0 again.

With a 12 ma injection, they should read 6551 (decimal) on the input word.
First 4 inputs work fine. It just might be faulty. I don't know what else to do.
 
i think you are right, probably a faulty card. Just pull it and look for any physical damage. If it looks alright, might as well try to substitute a known good card in its place. It might be a chip that is common to those inputs.
 
I have notified the vendor that sold this card to me. Maybe there can be an exchange.
Maybe not
First burn on ebay.
Thanks for replying
 

Similar Topics

Hello everyone, I am currently working on a project that uses a Rockwell L33ER controller and the FTV Studio V13 as Supervisory computer...
Replies
0
Views
84
Hello Friends I have a backup that I am trying t open in mi PC (RSLogix 17.01) and I get this message. I have read many posts and done many...
Replies
1
Views
135
Hi, Im trying to open an old old Siemens WinCC project. It doesnt have to run i just want to look at the project in WinCC explorer. Its...
Replies
2
Views
517
Hello. I cannot change the SendClock settings for a PROFINET IO device. I need to slow down the CODESYS PROFINET IO controller. What am I doing...
Replies
0
Views
175
Hi, I received the following project from a customer on a QuickPanel Proface 6" that I need to swap to a Siemens Panel. However, I cannot seem to...
Replies
3
Views
292
Back
Top Bottom