I have a B&R test stand PLC of which is a system generation 3 (PP15) and need to upgrade MY PLC for some project which seemingly could not be created on SG3. So I'm looking for a lower cost SG4 PLC (from X20CP family) for my test stand.
My power panel (PP15) has Just CAN, But I have AC 114 (Powerlink card) too, need not I/O I think, cause I use PLC just for testing.

Which PLC do you recommend on lower budget?
And Which modules?

Best regards