Airmar UDST800P-N2 Transducer Ultrasonic Smart Sensor

Overview

Built for cruising powerboat and sailboat owners who need reliable speed, depth, and temperature data without the headache of paddlewheel maintenance. If you run at speed regularly or spend time in shallow water where a paddlewheel gets fouled, this sensor eliminates that problem entirely.

The UDST800 combines depth, speed, and water temperature in a single thru-hull housing with no moving parts. You get ultrasonic precision that adapts to your boat speed and water conditions, updates 10 times per second, and feeds directly into your existing NMEA 2000 network. No more paddlewheel cleanings—just accurate data, every time out.

Key Features

• Ultrasonic Depth, Speed, and Temperature in One Housing — eliminates the need for separate depth and speed sensors — saves installation complexity and reduces points of failure on your network.
• No Moving Parts — no paddlewheel means no fouling in grass, no maintenance between trips, and no downtime waiting for parts — your sensor keeps working in conditions that would clog a traditional wheel.
• 10 Updates Per Second with Adaptive Filtering — corrects automatically for boat speed, water depth, and clarity — you get consistent, reliable readings whether you're trolling at 2 knots or cruising at 30.
• Speed Range 0.1 to 50 Knots — covers everything from dead-slow maneuvering to full-throttle cruising without loss of accuracy.
• Depth to 328 Feet — works in deepwater and shallow coastal runs; minimum 2 feet keeps you covered in shallow flats and rivers.

Specs & What's Included

Compatibility: NMEA 2000 output only—confirm your chartplotter or network display supports NMEA 2000 before ordering. Retrofits into Airmar P617V housing. Supply voltage 9 to 16 VDC (standard 12V marine systems). Water temperature range -4°C to 40°C (32°F to 104°F). Not sure if this works with your setup? Call or text us at (833) 831-4077—we'll tell you straight.

In the Box: UDST800P-N2 Ultrasonic Smart Sensor with plastic thru-hull housing (bronze and stainless steel options available). Mounting hardware and NMEA 2000 connector included. Installation into thru-hull requires a 2-inch diameter hole; professional installation recommended if you're not familiar with marine electrical work.