One of the leading Czech suppliers of PV plants is ARP elektro group s.r.o. In January 2025, the company launched an innovative PV control system – GreenBox. We have our fingers in it!
The GreenBox can intelligently control water heating in the boiler or charging of electric cars via the wallbox. Communication is via Microsoft Azure IoT and control is fully integrated into the mobile app. The development and production is carried out entirely in the Czech Republic.
We provided hardware and firmware development
Arpeg approached us with a request to design and manufacture the hardware of this unit, including the system firmware, i.e. customized operating system (Linux/Yocto) with configured peripherals, update solutions, connection setup functions and other details.
The development of electronic devices is not about marketing promises, but about daily honest work and precise engineering. GreenBox represents an evolution in photovoltaic control – not a revolutionary technology, but a sophisticated and precise solution tailored to the needs of customers. It is a demonstration of what we do every day: creating new functional, safe and reliable devices. This is what professional custom electronics development looks like in practice.
Technical Solution – EGModule and Functional Label with LEDs
The foundation of the unit is our Linux SOM module EGModule built on the ARM/Allwinner A64 platform. It runs at 1.1 GHz with 1 GB of RAM and full embedded Linux support (Yocto), along with 8 GB of flash memory. We developed the module a few years ago for our own use as a Replacing Raspberry Pi Compute Module 3. We have integrated Ethernet, RS-485 (Modbus-RTU) for industrial communication and USB ports for configuration and firmware updates. In addition, during the development process, we added a customer-requested and Wi-Fi connectivity.
The device is in a standardized box, designed for installation in a switchboard. Industrial designers did not get a say in this case – but the label is interesting in a different way: LEDs are integrated directly in the labelthat indicate the status of the unit, network connection and power supply. This has saved space and costs for a separate PCB with LEDs or light pipes inside the unit. We used common membrane keypad technologies.
The software application part was handled by another vendor, with whom we collaborated to connect our firmware with the Docker platform and Microsoft Azure IoT.
From prototype to series production
The development involved a complete process from schematic and circuit board design in Altium Designer, through prototyping to pre-series production of 50 units.
During this process, we worked closely with the software vendor to debug our system with the Docker-based application under development and Microsoft Azure IoT.
Now we have completed the final testing and certification without losing a flower, and we are starting the production of the first full batch of 300 GreenBoxes for the Czech market.
Without unnecessary exaggerations
The development of electronic devices is not about marketing promises, but about daily honest work and precise engineering.
GreenBox is exactly that – a thoughtful and precise solution designed to meet the exact needs of our customers. And that’s where its real value lies. That’s the kind of thing we invent and produce every day. We take a technical brief and turn it into a feasible, manufacturable and reliable product. This is what professional custom electronics development looks like in practice.
Contact us, we will be happy to help you too!
