PLC5 40E Input address addition

[BenL]

Hopefully this is fairly clear cut. I need to get a 4-20mA signal added to an I/O module of a PLC5 40 E. Using RSLogix5. There already is an identical input setup at a different physical location (pond level). I am just getting the reading added to the PLC so I can create it's field in HMI for operators. The backplane has 17 slots, two analog inputs and 2 analog outputs. The analog input modules have wires terminated on every channel. But I see two wires I know are inputs terminated onto the analog output modules where there are open channels remaining.

Basically I just need a little guidance on 1.)if I can terminate input to an output card? It doesn't seem logical, but it appears like it's being done.

2.)Once I get the input physically created, how do I find the internal address to create the HMI link? Is it in data tables? Will making the physical connections, then power cycling the backplane auto read the new channels on the module?

That's it for now. I'm sure I'll have more questions as I dive into this. I was trained on Contrologix and this is a bit different than that. Any info/guidance is very appreciated!

Thanks!

 

[RonJohn]

Welcome aboard, Ben.

If you haven't already discovered, PLC5 is not quite as intuitive as the Logix platform. I was weaned on the 5, but don't use it as often nowadays, so let me throw out a quick thought or two.

First & foremost, get a copy of the user manual for the module you're working with. PLC5 software doesn't have an i/o configuration like Logix. Block transfers were used to read/write data from/to analog I/O modules. The data structure is different for each module. Can't tell what goes where without that manual.

Secondly, I didn't quite figure out if you were adding an input or an output and if it was going on an existing module. Please clarify and let us know what type module you're dealing with. You can only add an input to an "output" module if it's a combination i/o module.

If it's an existing module, the block transfers are probably set up. If it's a new module, it would be helpful to know which rack/group/slot the module is mounted so that someone can help you set up the block transfers.

Hope this helps.

 

[Ken Roach]

Welcome to the Forum !

What is the exact part number of the analog modules ?

Unfortunately RSLogix 5 can't identify them over the backplane; you need to physically view a part number on the front or the side.

The only "combo" analog modules were the 1771-Nxx series, which were less common and more complex than the usual 1771-IFE or 1771-OFE2.

It would not be unheard of for "spare" wires to be terminated in the wrong place.

In the PLC-5 program you're going to need to look for Block Transfer Read and Block Transfer Write (BTR/BTW) instructions. Those are the method that the PLC-5 used to transfer non-discrete data from modules to the PLC memory.

It's definitely more of a manual process than just enabling a module channel like it would be in a Logix family controller.

 

[Bit_Bucket_07]

Basically I just need a little guidance on 1.)if I can terminate input to an output card? It doesn't seem logical, but it appears like it's being done.

No. You cannot connect an analog input to an analog output module. I mean, you certainly can physically make the terminations, but you cannot make an analog output function as an analog input.

2.)Once I get the input physically created, how do I find the internal address to create the HMI link? Is it in data tables? Will making the physical connections, then power cycling the backplane auto read the new channels on the module?

The I/O address depends upon the system configuration. PLC5 analog I/O is transferred to the I/O Image table via Block Transfers. You will need to become familiar with the I/O System configuration in order to find the BTW and BTR functions associated with each specific analog I/O module. Cycling the power will not do anything for you.

 

[Mickey]

Post your .RSP file (zip it first). If you are lucky the I/O may have been configured.

Someone can help you look for the addresses you need.

It would help if you can list the I/O modules from left to right as they appear in the chassis.

 

[BenL]

Thanks for all the feedback. It is a 1771 IFE A Analog input module. There actually are three channels vacant, 10 the module common, 11 and 12. Maybe I can use them if they aren't bad and the module should already be configured?

From left to right, slots are: PLC5 40E Processer, Power Supply, 10-30V DC Input, 10-60V DC Output, empty, 10-60V DC output, 4 empty slots, 12 Digital Output, 12 Analog output, DH+ Network card, 12Bit Analog Input, 12 bit Analog Input, 12 Bit Digital Output.

Vacant channels are on pins 8,9,10 slot 15 (second to last). One thing that puzzles me is the existing pond level input, F65:51 has a cross reference value but I cannot find it's place in the program. That address wasn't in any of the BTR BTW operations. I will try and find the module manual online somewhere.

 

[RonJohn]

I will try and find the module manual online somewhere.

Here's a link to the A-B literature library webpage .

On the right hand side, enter the part number where the search box says "search here..." You'll want the user manual. There probably won't be one for the series A model of 1771-IFE, but the series C manual describes the differences.

Please note that the wiring varies based upon whether the card is set for single ended or differential inputs.

 

[Ken Roach]

F65:51 has a cross reference value but I cannot find it's place in the program.

It's probably just a member of a block of addresses. That will show up in a cross-reference, but only the first member of the block will show up in a specific Copy or similar data file handling instruction.

You won't find the F65:xx address directly in a Block Transfer Read instruction. Data from a 1771-IFE arrives in Integer format, so you will probably find some file Copy and MOV or DIV or MUL instructions before the data eventually lands in F65:51.

 

[BenL]

Here is a compressed .rsp file of program. Basically just trying to trace out the physical input connection to the internal address. I will be recreating the same scenario on another device. The application is a remote lake level float meter. Analog. The local PLC at the meter is a Micrologix. All I can see at the PLC5 40E is the destination address value in the cross reference.

 

[Mickey]

Data in F65:51 is coming from a message instruction Lad 11 rung 75.

So what ever is connected to channel 0 is where the data is coming from. See picture

 

[Mickey]

For the PLC'5 analog input cards (the 1771-IFE's) see pictures below for the addresses.

Block transfer reads (BTR) instructions for these cards are in lad 12 rungs 3 and 15

 

[bodri]

an interesting thread. join the team hopefully got enlightenment.

 

[BenL]

Great info, thanks everyone! Where did you get the module configuration menu? I apologize about my ignorance, but this seems a very roundabout way compared to Contrologix. With that, you could drop down select the I/O, and the local addressing was straight forward. This is a bit confusing.

So what it sounds like is I probably won't be able to simply find the address of the vacant analog input module, install the signal wire, find the data table address where it's being stored and then point the HMI to that dest address?

 

[Mickey]

Where did you get the module configuration menu?

In a PLC5 the I/O configuration is optional, its for documentation only.
If you know the slot the card is in you can then put it in the I/O configuration, also need the catalog number. The software will then ask for a control word file and a data word file. Because they already exist you can ignore this step. The software is smart enough to recognize the words already exist and will give you the screen shots I posted when you double click on the block transfer instructions.

So what it sounds like is I probably won't be able to simply find the address of the vacant analog input module, install the signal wire, find the data table address where it's being stored and then point the HMI to that dest address?

Not true, the screen shots I posted provided the addresses needed to find the info in your program. In the file you posted there are some additional programming to change the BCD data from the card to to an integer, look for "FRD" instructions.

Even without the I/O configuration screen shot a review of the instruction set ( BTR/BTW) instructions will help you find the correct addresses.

 

[BenL]

The above scenario is a Micrologix 1500 CRP communicating I/O back to the PLC5 40E over radio transmission via MDS 9810 Data Interface on Channel 0 serial port.

In trying to understand the data flow here:

An example is the data file was copied from the remote Micrologix (#I:1.0 to #N7:2) transmitted back to PLC5. Written to N75:2 as MSG control MG66:13. If I created a new input at the Micrologix, and performed the same COP, MSG functions, the data file would be created at the PLC5 more or less the same? I would just input the correct data table/station addresses during the creation of the MSG function?