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Airmar
Airmar UDST800 Thru-Hull Ultrasonic Smart Multisensor
Item: #932677 | Part Number: Not Selected$1,500.00 - $1,725.00
Description
Airmar's UDST800 Ultrasonic Smart Multisensor uses ultrasonic technology instead of a paddlewheel to provide accurate speed, depth and temperature via NMEA 2000. The UDST800 uses Airmar's patented adaptive signal processing to constantly calculate boat speed based on water clarity and depth to generate updated speed data, delivering it to your...
Airmar UDST800 Thru-Hull Ultrasonic Smart Multisensor Item # 932677
Description
Airmar's UDST800 Ultrasonic Smart Multisensor uses ultrasonic technology instead of a paddlewheel to provide accurate speed, depth and temperature via NMEA 2000. The UDST800 uses Airmar's patented adaptive signal processing to constantly calculate boat speed based on water clarity and depth to generate updated speed data, delivering it to your network up to 10 times per second.
Features:
- Ultrasonic depth, speed, and water-temperature sensor
- Provides precise readings at high speeds - ideal for powerboats, cruising, and sailing
- Keeps speed accuracy consistent by adapting automatically to boat speed, water depth and water clarity
- Utilizes two ultrasonic transducers, to measure the time it takes for particles in the water to travel between them
- 235 kHz frequency prevents interference with other echosounders on the vessel
- Thru-hull, low-profile housing with water valve
- No paddlewheel to clean or maintain - no moving parts to break or wear out
- Retractable insert for safe storage
- Retrofits to existing Airmar P617V, B617V or SS617V housings
- Includes Ultrasonic processer and blanking plug
Specifications:
- Recommended application:
- Bronze: fiberglass or wood
- Plastic: fiberglass or metal
- Stainless Steel: all materials
- Deadrise angle: Best performance through 7°. Accommodates up to 22°
- Frequency: 235 kHz
- Depth range: 0.6 to 100 m (2 to 328')
- Speed:
- Range: 0.1 to 50 knots (0.1 to 57 mph)
- Transmitting frequency: 4.5 MHz
- Output: NMEA 2000 - depth, speed and temperature
- Data update rate: Up to 10 times/second
- Supply voltage: 9-16 Volts DC
- Supply current: 80-200 mA: average 125 mA @ 12 Volts DC
- NMEA 2000 Load Equivalency Number (LEN): 8
- Operating temperature range: 14° F to 104° F
- Water temperature accuracy: ±1.8° F
- Sensor cable length: 6 m (20')
- Certifications and standards: CE, IEC60945
- Hole diameter: 51 mm or 2"
- Weight: 4 lbs
Part Numbers for Airmar UDST800 Thru-Hull Ultrasonic Smart Multisensor
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Reviews
Rated 3 out of
5
by
Tom W from
Not what I had hoped for.
I have been disappointed by this sensor. Regarding each of the 3 sensors: the temp sensor is fine; the depth is not as sensitive as the one on the traducer it replaced, sometimes failing to read over soft bottoms; and the speed sensor has 3 problems. It reads high, maybe 8% on average. Next is that it “wanders” in speed sometimes being off considerably more or less and finally there seems to be no way to calibrate it across the whole system. I have to calibrate each display. This makes me suspect that the wrong data is going into the calculation of things like true wind speed and direction. FYI it is part of a B&G system (current) and is installed very close to the centerline, well forward of the keel in what should be an ideal location. Yes, cleaning is less of a problem but the other issues make me recommend that you save your money.
Date published: 2025-10-02
Rated 1 out of
5
by
khack from
hindsight - would not purchase again
installed this early August, been in the water for 6 weeks now. The speed and temp work spot on, the depth however, fails horribly. Full keel mounted as described in their installation docs, and with 41" below this depth meaning I'm on the bottom, the transducer actively reads that i'm in 23" (1.9') of water. Throwing a line under the boat shows i'm in just over 10' of water. I thought this was an offset issue, but being there is no offset option for this transducer, I decided to read it in and inject an offset via signalK. This just merely added an offset to an erroneous reading. Watching the depth reader as tides come in and go out shows no fluctuation at all. Watched the tide (and storm surge) come in raising the water levels from hurricane by 3+', still shows 19" of water below the boat. I emailed airmar, they have offered no assistance other than "it may be growth". Wishing I just bought a cheaper transducer.
Date published: 2025-09-15
Rated 4 out of
5
by
Sailor Nate from
Works well but can’t be calibrated by Raymarine
After installing, my Raymarine Lighthouse 4 software immediately recognized and displayed all data from the new unit even though my prior Airmar 800DST was still connected (but no longer in the through hull). The only problem is that I can not adjust the offset for the depth sounder or calibrate the speed. Luckily the speed seems very accurate. I adjusted my depth alarm to compensate for the lack of offset and will slowly get used to the new readings. The 850 series apparently has Bluetooth and can be calibrated via Airmar app. Something to consider.
Date published: 2024-08-03
Questions
Does the Airmar UDST800 come with the following: - through hull housing - blanking plug - NMEA data cable (how long?) - non-valve housing o-ring (20-519-01)
Yes, this item comes with the housing, blanking plug, and a 6m cable that connects the sensor to the box. This also comes with the o-rings needed for install with or without a valve.
Date published: 2025-01-13
What adapter is required to connect this to a Raymarine SeaTalk NG network?
SeaTalk NG to DeviceNet (NMEA2000) Adapter Cable, Female
Date published: 2025-01-13