Analog Input Signal

I have a Analog input signal that I need to send to one of my Analog outputs so the signal can be shared with a 3rd party to one of there inputs.

To make sure that I’m doing this correctly, can this be done within the PLC program? If so how would I do this? Can I use a MOV instruction to move the input signal to a output?

I was wanting to accomplish this without buying an analog signal splitter if at all possible.

I appreciate the help

Thanks

Yes, just move from AI to AO, and ensure the scaling on both sides match.

Thanks Ken
I appreciate your help

One thing to look at is the resolution of the input and output. The AI and AO might have resolutions of different numbers of bits.

For instance (and this is just and example) if the AI is a full 16 bits, you could get numbers at the input of 0-32767. Then if the output is 12 bits, only the values 0-4096 will be valid. Depending on your hardware and system, larger values might get truncated or it might throw and error.

You should check the valid ranges of the Ai And AO and make sure all possible values at the AI are valid at the AO. If not, you will need to scale the signal to fit the AO range.

In addition to the comments above, if you are moving raw values, make sure they match. Some cards (For example, the Allen Bradley Analog I/O) allow you to use things like Engineering units (4000-20000) or percentages (0-10000)

Make sure the input and output match or are otherwise scaled to match.

Thanks again
I appreciate the explanations, this is a huge help!

You could always use one of these ->

https://www.prelectronics.com/about-pr/news-and-events/news/3109-signal-splitter/

Rson said:

In addition to the comments above, if you are moving raw values, make sure they match. Some cards (For example, the Allen Bradley Analog I/O) allow you to use things like Engineering units (4000-20000) or percentages (0-10000)

Make sure the input and output match or are otherwise scaled to match.

Click to expand...

How would I move the input to my output card and have it read as a “Real” value instead of a interger?

Thanks

Ones_Zeros said:

How would I move the input to my output card and have it read as a “Real” value instead of a interger?
Thanks

Click to expand...

If I understand correctly, you want to scale the AI and then have the 3rd party device receive/have the same scaled value? Move the value of the AI to your output (has to be DINT, not REAL). The 3rd party will need to have its input scaled the same, as stated by others.

It sounds like you may still need to get a handle on what is happening when you bring an analog signal into the PLC. See if the attached diagram helps.

Going the other way is the exact opposite. In your case, your analog output would stop at the other plc so it ends up as an electrical signal.

Using a scaling instruction or math, you need to convert your engineering value to a number in the range that your analog input can handle. The analog output will convert that number to an electrical signal based on the number of bits it uses and the type of analog signal it outputs. then you need to communicate to whoever is programming the other PLC how you scaled the signal and what the voltage 'means'. For example you would tell them something like "The analog output is 0-10VDC which will represent 0-3000 psi pressure."

mad4x4 said:

You could always use one of these ->

https://www.prelectronics.com/about-pr/news-and-events/news/3109-signal-splitter/

Click to expand...

This would probably be your best option. Even if the PLC would go down the secondary controller would still receive the signal.

These splitters though usually need to be powered so you would need to pick where the power source comes from to be reliable for both systems.

Norm,


I can see that you've told that story more than once . . . Yup.