4G SMS-Controlled Gate Opener

A compact GSM 4G-controlled door opener designed for secure, remote operation of gates, garage doors, barriers and shutters. Built around quad-band (850/900/1800/1900 MHz) 4G connectivity, it delivers consistent signal reception across diverse UK and European locations — including urban, suburban and semi-rural zones. Physical dimensions are approximately 125mm in length; power input is flexible at 9–24V DC (2A max), with typical operating current at just 25mA when supplied with 12V. The relay output is a versatile NC/NO dry contact rated 3A/250VAC — directly interfacing with common door mechanisms and industrial controls. It supports standard 3V SIM cards and connects to external antennas via a 50-ohm SMA interface. Rated for continuous use from -20°C to +60°C and up to 90% relative humidity. Authorisation is managed entirely by SMS: store up to 200 trusted phone numbers, adjust relay hold time per command, and enable or customise confirmation SMS replies. Incoming calls from registered numbers are auto-rejected on the first ring — triggering immediate relay action without voice call costs or delays. Confirmation messages can be sent to the owner or any configured number, and edited on-the-fly. Use cases include private driveway gates, shared building access points, warehouse loading bay doors, and retail shutter controls — especially where Wi-Fi is unavailable or insecure, and traditional remotes lack scalability or auditability.