Success story of Dinokeng Game Reserve, South Africa. Gañar Group upgraded the gate access control: the old wired RS485 system at 5 entrance gates had become too costly to maintain. The new system uses a Wi-Fi network, a central gate controller software with a cloud database, barcode and QR tickets on the existing Star TSP700II slip printers, and ESP32 PLC 19R units at the entrance and exit gates. The PLC reads the No Touch sensor and the Ticket Taken signal, opens the boom and shows the result on a 2-line LCD. On bare ESP32 chips, electromagnetic noise caused hang-ups; on the ESP32 PLC 19R the shielding was a vast improvement, and an external antenna typically raised the RSSI from -80 dB to -50 dB.

The PDF covers the challenge, the three loops (entrance, check, radio link), the system architecture with the signal list, real photos from the gates and the hardware used. Interactive version: gate access control success story online.