Red Lion G3 string tags and Modbus TCP/IP

Hello all,

Before i go replacing the Red Lion G310R10 HMI i have purchased for a project i am building i thought i would see if anyone in the community may have some advice for me.

I have a P3000 PLC with a number of different String tags in its database (all are 20 characters). They all have modbus addresses assigned to them, for example tag "test" has the address space 400100 - 400109 assigned to it. I would assume they are packing 2 characters per 16 bit address.

I am trying to read and manipulate these tags through the above mentioned HMI, which i swear i had done before with an 8" G3 HMI and crimson 2.0

However i am unable to get this to work in Crimson 3.0

Red lion tech support informed me that thier modbus TCP/IP master driver does not support strings, but the software does allow me to select and assign an address to the string tag and specify the method of packing (ASCII little or big endian).

Is this is problem there is no solution for? I really dont want to buy a cmore hmi to replace this unit as i have standardized on the G3 hmis for a couple of years now. But automation direct has confirmed the cmore can read the string tags from the PLC with thier own built in driver.

Any advice would be appreciated.

You may have to write a script to decode the data if the Modbus master is going to try to interpret it as an integer.
Convert the low byte of the first word to an ASCII character.
Divide the high byte of the first word by 256, convert to an ASCII character and concatenate with the previous character.
Convert the low byte of the second word to an ASCII character and concatenate with the previous characters.
Divide the high byte of the second word by 256, convert to an ASCII character and concatenate with the previous characters.
Lather, rinse, repeat....

Get rid of it. The G3 is a troublesome piece of junk. I've used a lot of them because of the protocol converter and the web access functions, but as a regular HMI, they're junk, and C3 is a real pain to get to know. I've been using Cmore ever since they came out, and have only had 1 fail in the field. Cmore reads string data from just about any PLC really well, and is a good, albeit an import, HMI.

I thought i should provide a update to this problem, as it is now resolved.

After trying every possible combination of tag format ect with modbus tcp/ip i noticed that red lion does have an encapsulated modbus master driver for the g3 which offers a MODBUS ASCII mode operation. My excitement was short lived as after trying this mode it was apparent the P3000 doesnt support it.

Before attempting to go down the patch the one member suggested of some custom scripting i decided to try modbus RTU. I ran a 2 wire RS485 to the panel from the PLC, plugged in the tag in and after selecting the ASCII - big endian packing method for the string tag, IT DISPLAYED JUST FINE!!!!

I am not sure why Modbus RTU works, but not TCP/IP but running a serial connection for these tags is not an issue for me with this project.

So for anyone else who runs into this here is my config details.

P3000 requires no special config other than the string tags need to have a modbus address assigned.

On the G3 I used the Modbus universal RTU master driver on the RS485 port. For the tags you configure the string length and you must select the "array" function for the tag and specify the size of the array (10 character string/ 5 word array). Select ASCII Big-endian encoding and away you go.

Thanks to everyone for the responses!

And as a side note to this post, The OPC server functionality for linking multiple G3's together works flawlessly. What a time saver, thank you Red Lion!