ScadaPack 32-Bit Modbus KepServer

[elmatador]

Hello Everyone,

I am having some major issues here. In SCADAPACK, all analogs are declared as 32-bit values. For example:

PRESSURE_SCALED (32-bit) has a MODBUS address of 44000

What SCADAPack does is it stores the values as follows:

44000 (Bits 16-31) upper 16-bits
44001 (Bits (0-15) lower 16-bits

So in kepserver whenever I read a Long, the value is garbage because it is expecting the following instead:
44000 lower 16-bits
44001 upper 16-bits

How do I get around to fixing this?

Please HELP!!

 

[Mickey]

The value in the SCADAPack is a Floating Point value, not a long integer.
I don't know Kepware, does it have an option to read a Floating Point (real) value?
Also some software will give you the option to swap words. Will Kepware?

http://www.kepware.com/Spec_Sheets/Modbus_Serial.html

 

[elmatador]

Thats the problem. I need to figure out a way to swap the order in KepServer. Keep in mind that this is the KepServer Enterprise Edition being used to communicate to FactoryTalk View.

This is driving me insane! I hope I dont have to move all this in my controller logic, it will be painful.

I will let you know if i find a way to do this.

 

[Mickey]

Kepware support is probably your best source. Their is a forum member who works for them.
see links below.

http://www.kepware.com/

http://www.plctalk.net/qanda/member.php?u=44495

 

[elmatador]

Hi Mickey,

While I messing around with some settings I found these. Now its working. I want to attach my screenshot but having troubles. Will need to read the stickies. I will post the screenshot for the proper settings so that fellow programmers dont waste too much time on this.

 

[elmatador]

Here is the picture with the settings. It is working now. Thanks Mickey, you brought about the epiphany in me.

 

[elmatador]

You just need to make sure you uncheck the following:

FIRST WORD LOW IN MODBUS 32-BIT

When unchecked, it will treat the second word as low.

Meaning:

PRESSURE 32-BIT: SCADAPACK MODBUS ADDRESS: 44001

HIGH WORD: 44001
LOW WORD: 44002

WORKS GOOD!!

 

[Mickey]

Your Welcome.
Thats a pretty common feature for Modbus stuff. Modbus is a very loose standard.