This scale is designed to work with a pc and be able to interface with other pc based applications and not directly with a plc. Not to say that you can't make it work somehow but I doubt the effort and cost are worth it.
If you need to interface with a plc it would be better to try and find a scale that will work with the plc directly.
I do a lot of Allen Bradley work and normally choose Hardy for all my scale solutions as they have very tight integration with Allen Bradley plc's.
Not sure what would be the best brand to use with Panasonic as I have never worked with that brand plc before but finding a scale that can work directly with the plc would be the easier road IMHO.