Surface mount easy install NMEA radar tank sensor

Non-contact radar tank sensing, built for the maker. The GBMS Radar Tank Sensor reads your fluid level using high-frequency radar pulses instead of a float or probe — so nothing ever sits inside the tank or touches the liquid. It surface-mounts to the outside of the tank with the included 3M adhesive backing and measures into the space above the fluid, giving you accurate, drift-free readings without the mechanical wear points that plague traditional float senders.

Designed and built at Garden Bay Maker Space for fuel, fresh water, and waste tanks, with output options that connect to virtually any system — from a modern NMEA 2000 network to a vintage analogue gauge.

Why radar?

• Nothing inside the tank. The sensor mounts externally and reads through into the airspace above your fluid — no float arms, no corrosion, no moving parts to fail.
• 1mm resolution. Industrial-grade sensing tells you exactly how much fuel or water you have left.
• Accurate from 150mm to 2000mm. A wide measuring range covers everything from a small day-tank to a large bulk tank.

Understanding the 150mm deadzone

Radar needs a minimum distance to resolve a clean return. Within 150mm of the sensor face there isn't enough room for the pulse to reflect back reliably, so this band is treated as a deadzone. In practice, once the fluid surface rises to within 150mm of the sensor, the tank simply reports 100% / full. Position the sensor so that this deadzone sits at the very top of your usable range and you'll get accurate readings across the rest of the tank.

Smart connectivity

Simplify your boat's electronics. The rectangular sensors can wirelessly daisy-chain together over a mesh connection, so you can monitor several tanks with only the final sensor needing a physical NMEA cable run — less wiring, less clutter, less cost.

• Wireless daisy-chain across multiple sensors
• Reduce cable clutter and installation cost
• NMEA 2000 plug-and-play

Easy install

Surface-mount with the provided 3M adhesive backing — no drilling and no complex brackets. Fits standard tank ports or a custom mounting plate, and is up and running in minutes.

Flexible power & output

Run the sensor directly off a 12V system or power it over your NMEA 2000 backbone (PoN). Output is available over NMEA 2000, Bluetooth, and analogue (voltage / resistive), so it works with all major display brands as well as older gauges.

Specifications

Currently available for pre-order — early-stage discount applied at checkout.