Gilbarco Two-Wire Protocol is a proprietary communication standard used to connect Gilbarco fuel dispensers to Point of Sale (POS) systems and site controllers. For third-party developers, implementing this protocol is essential for controlling fueling transactions, managing presets, and retrieving real-time data from forecourt equipment. Technical Overview The protocol operates as a multi-drop current loop
Loop Capacity: Supports up to 16 fueling positions on a single communication loop. then to dispenser 2
Подключение ТРК Gilbarco - Сибнефтекарт 7 data bits
Topology: A multi-drop loop supporting up to 16 fueling positions on a single pair of wires. Communication Model 1 stop bit |
The Gilbarco dispenser two-wire protocol is a widely used communication standard for integrating third-party pump controllers with Gilbarco dispensers. Its simplicity, flexibility, and interoperability make it an ideal solution for fueling operations. By understanding the protocol's details, developers and integrators can design and implement efficient and accurate fueling systems that meet the needs of their customers.
The master (third-party controller) sends a 2-byte address + command. The dispenser responds with data.
| Parameter | Specification | | :--- | :--- | | Physical Layer | 20mA Current Loop (not RS-232 voltage levels) | | Topology | Daisy-chain (one pair of wires from controller to dispenser 1, then to dispenser 2, etc.) | | Wire Type | Twisted pair, shielded (Belden 8760 or equivalent) | | Max Distance | 2000 ft (600m) per loop | | Communication | Half-duplex, asynchronous | | Baud Rate | 1200 bps (fixed, non-configurable on most legacy dispensers) | | Data Format | 1 start bit, 7 data bits, even parity, 1 stop bit |