Reading something simple using 60870.5

[AkashSharma]

I'm new to IEC 60870.5.  I need to read data using this protocol.

I have the IP Address of the machine that has access to the data.  I guess that is called the Master (?). I was given a document with a bunch of "104 Addresses".  I'm guessing those are "IOA"s (?). The same document I mentioned has a couple of other numbers that seem to apply to several of the "104 Addresses".  They are labeled "Nr." and "Number".  I'm guessing those are "ASDUs" (?).  Unfortunately I don't have much access to the folks who actually put that doc together.

One of those 104 Addresses is for a measurement labeled "AC voltage". I believe the value is simply a DBL. To read it I built a VI (snippet attached), except I don't know what to insert where the Question Mark is.  Can someone suggest what goes there?  I tried using the "Read Parameter.vi" function but that generated error -355269 stating "NI-Industrial Communications for IEC 60870-5:  This type of points does not have parameters."

I tried following the examples, but I got confused. Probably just me!

Thanks in advance for any help!

[j_bou]

Hello AkashSharma,

Which example VIs did you try using? I agree that some of the advanced examples can be intimidating but the general examples are relativity simple. The “Write Single Point.vi” example is concise. I would recommend using that VI as a starting point.

I attached the example files for your convenience.

Regards, 

j_bou

[AkashSharma]

Thanks. Is there a "Read Single Point.vi" example somewhere? Also I notice a "Write.vi" in the toolkit. I don't see an equivalent "Read.vi". Is that floating around somewhere? Lastly, in "Write Single Point.vi" what does the word "Single" mean? Does it mean SGL? Or does it mean "not an array"?

Thank you!

[LewisL · Accepted solution]

Hi AkashSharma, Indeed the VI examples are a much better starter than making it on your own when you are not very familiar with the protocol. There is no "Read Sing Point". The NI IEC 60870-5 toolkit only has the controlled station part of functions. A controlled station (or server, slave) writes data to the Controlling station (or client, master). The controlling station gives commands to the controlled station, and monitors for points on them. Check out the Commands VI palette, and you'd find Read Command.vi. The Single means point type. Check out the VI context help and detailed help for a list of point type definitions.

[AkashSharma]

That helps! Thank you!