I see this time and time again in the controls field. Though we may cross over with the IT sector, machine control is a completely different beast. It isn't about swapping out a computer. There are a plethora of closed communications protocols, old SCADA-package-specfic libraries and binaries, and lots of those functions in the script have to be rewritten. It is great when you have a PLC doing the controls and the SCADA package acting as an HMI, because you can develop the new system in parallel to the existing one, but if the PLC does not do a good job of handling the data transfers, you could be in for a world of hurt.
The hardware and OS are often out of date within two years, and you are looking at upwards of $15-20K to upgrade a single machine so that it can run and updated OS and SCADA package. Upgrading the PC platform is easy, though, compared to upgrading a PLC. You could potentially have thousands of wires that must be migrated over, and a program that must be re-written to the new platform and meticulously checked for errors by someone that knows what the are doing. You must also bring the system down to perform the upgrade, hence the reason why most of our nuclear systems are still on PLC-5 systems. The hardware is still available, rock-solid and reliable.
There is a lot more involved when you start digging into controls than there is when dealing with server and network issues. Once you start opening up that can of worms, you are in it for the long haul, and when you add a significant shortage of people trained as both electricians and IT guys, that makes matters worse.
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I see this time and time again in the controls field. Though we may cross over with the IT sector, machine control is a completely different beast. It isn't about swapping out a computer. There are a plethora of closed communications protocols, old SCADA-package-specfic libraries and binaries, and lots of those functions in the script have to be rewritten. It is great when you have a PLC doing the controls and the SCADA package acting as an HMI, because you can develop the new system in parallel to the existing one, but if the PLC does not do a good job of handling the data transfers, you could be in for a world of hurt. The hardware and OS are often out of date within two years, and you are looking at upwards of $15-20K to upgrade a single machine so that it can run and updated OS and SCADA package. Upgrading the PC platform is easy, though, compared to upgrading a PLC. You could potentially have thousands of wires that must be migrated over, and a program that must be re-written to the new platform and meticulously checked for errors by someone that knows what the are doing. You must also bring the system down to perform the upgrade, hence the reason why most of our nuclear systems are still on PLC-5 systems. The hardware is still available, rock-solid and reliable. There is a lot more involved when you start digging into controls than there is when dealing with server and network issues. Once you start opening up that can of worms, you are in it for the long haul, and when you add a significant shortage of people trained as both electricians and IT guys, that makes matters worse.