Disclaimer: Gilbarco Veeder-Root is a registered trademark. This article is for informational purposes. Always consult with a certified fuel systems integrator and adhere to local electrical codes (NEC Article 514) before modifying dispenser wiring.
The Gilbarco two-wire protocol is a (0–50 mA typical) used on Gilbarco dispensers (e.g., Encore 500, 700, Eclipse, and earlier Highline models). It allows a remote controller to:
Controller approved transaction; waiting for flow. Disclaimer: Gilbarco Veeder-Root is a registered trademark
: Communication is achieved via a 20mA or 45mA current loop. Third-party controllers usually require a hardware interface or "D-Box" (Distribution Box) to convert standard serial signals (RS-232 or RS-485) into the specific current loop required by the dispenser. Data Parameters : Typical settings vary by dispenser model: Legacy (Highline-2, Euroline) : 4800 baud, 8 data bits, Even parity, 1 stop bit. Modern (Encore, SK700) : Often referred to as "Corporate baudrate" at , 8 data bits, Even parity, 1 stop bit. Data Format
Third-party controller manufacturers utilize this protocol to: The Gilbarco two-wire protocol is a (0–50 mA
A single communication loop can support up to 16 active fueling positions .
+---------------------------------------------+ | Third-Party Pump Controller (Master) | +---------------------------------------------+ | (+) Current Loop Source | (-) Return v ^ =========#=============================#========= (2-Wire Trunk Line) | | +------#------+ +------#------+ | Dispenser 1 | | Dispenser 2 | +-------------+ +-------------+ Electrical Characteristics linking forecourt controllers
The is the undisputed global benchmark for retail fueling communication, linking forecourt controllers, Point-of-Sale (POS) systems, and fuel dispensers into a singular, synchronized data stream . As modern service stations transition toward hybrid fueling options, IoT telemetry, and multi-vendor hardware configurations, the demand for third-party pump controllers capable of natively decoding this proprietary architecture has skyrocketed.
If you are currently developing or debugging a third-party pump controller interface, let me know which stage you are working on. I can provide explicit details on the , clarify the exact byte sequences for specific pump commands, or help troubleshoot hardware circuit designs for the active current loop interface.
This is a popular third-party universal controller. The PTS Controller Technical Guide details how to bridge third-party systems to Gilbarco dispensers.