There will be many valid opinions regarding this topic, so I will provide my 'look' at this situation.

Accepting that industrial manufacturers, taking SIEMENS as an example, must continually move on, with both hardware and software. Driven by cost, innovation, and perhaps mostly by customer pressures, perceived and imagined. If they fail in this regard market position will be lost, and consequent competitive position and profitability.

The modular approach of G120 was an excellent concept; power stack satisfied the power demand in its various forms, whilst the control module catered for applications of control, serial, digital, vector, and feedback. Control contained within the control module enabled swift changes of device, reduced downtime, and diagnosis.

Design and concept changes have always created anguish for the 'owner' of the process. Driven by installed base of component with regard to a new machine installation with spares, to replacing expired components within an existing installation, regarding communication and operation, to will the replacement device fit the space, not forgetting 'who' can recall the configuration, after some years of operation?

As components become unavailable due to processes which require massive components runs in order to maintain viability, or perhaps pure lack of material; here manufacturers may be notified of the end of life of a device, ASIC, or processor. At this point a device life for the inverter drive must be predicted, and forward purchase of many years of components to maintain production, this may define the point at which redesign a new product.

The process of design, test of hardware and full system test, for software, and certification, for a replacement device, in order to absorb the new requirements, is the dynamic life of a manufacturer with an eye to future production. The fail here is to loose the dynamic front line position within an industrial sector, and profitability.

I have tried to list some of the detail which I have seen, and experienced, I hope this will help you with your situation.

As always come back if I can help further.

P.s. with the S220 the drive must be replaced..

Tractor