Our former control system IDE-CC-Control is only 7 years old, but we thought that its range of functions isn’t really up-to-date anymore. Instead of doing some kind of touching-up towards today’s state of the art, we decided to develop a completely new digital control system.
In order to equip our new digital compressor controls IDE-HMI TCC with a truly optimal set of useful functions and utilize all digital possibilities, we discussed a lot and spent a lot of time on the functional specifications document for our software engineer.
Of course, the hardware, its features and components need just a much attention to detail and require many individual decisions. For instance, shall we use a high-quality, high-definition 7’’ multicolor touchscreen with scratchproof Digitizer glass, that offers a clear and legible display, operational safety, durability and ex protection, but is expensive? Or should we rather use a membrane keyboard, which is considerably cheaper, but over time can chafe around the keys, which is not as clear and is unsuitable in terms of ex protection? In the end we chose the Digitizer glass touchscreen. We added an extremely large data memory and a strong and fast processor. Android is our programming language.
A particular focus lay on the service feature of the digital control unit. Since the system is based on Android, the cheapest and easiest way would have been to run the service function in a mobile app (app is short for application software, small application programs for smartphones or tablets, e.g. for work, fun, games, recreation or hobby purposes).
After careful consideration we dismissed this idea – for safety concerns and because we think that an app doesn’t actually go well with industrial digitization, i.e. industry 4.0.
An app would interface with the compressor controls via Wi-Fi, but cellphones and Wi-Fi offer hackers the easiest access to company servers and data, a security code not making much of a difference here.
Neither is it useful to send error messages and error codes to a cellphone via Wi-Fi, as the Wi-Fi signal will be lost a few yards outside the house.
For reasons of safety and liability it is unreasonable to use a cellphone for error acknowledgement or as a remote control to start or stop the compressor.
Therefore, we decided to use a modem, which is safe and conforms to the rules. Our new HMI-TCC control system is equipped with a GSM modem, which in case of an error immediately sends a text message to up to two freely selectable phone numbers, for instance to an external service technician who can then initiate whatever is necessary.
The modem comes with its own SIM card; IDE bears the text messaging charges.
Of course the IDE-HMI-TCC is capable of so much more, and here you can learn all about it: