Airmar TRIDUCER Smart UDST800 Owner's Manual

OWNER'S GUIDE
Thru-Hull Mount:
Ultrasonic TRIDUCER
Model UDST800
Patent http://www.airmar.com/patent.html
Follow the precautions below for optimal
product performance and to reduce the risk of
property damage, personal injury, and/or death.
WARNING: Always wear safety glasses, a dust mask,
and ear protection when installing.
WARNING: The valve is not a watertight seal! Always
install the insert or blanking plug. Be sure it is fully
inserted into the housing and the cap nut is screwed on
completely for a watertight seal.
WARNING: All the O-rings must be intact and well
lubricated to make a watertight seal. Do not dry fit the
insert in the housing. Attempting to install the insert
without lubricating all the O-rings may damage them,
possibly preventing full insertion and a watertight seal.
WARNING: The YELLOW O-ring must be in place near
the top of the insert to make a watertight seal.
WARNING: To retrofit the insert in a housing without a
valve, the insert must have a BLACK O-ring near the top
to make a watertight seal.
WARNING: Always attach the safety wire to prevent the
insert or blanking plug from backing out in the unlikely
event that the cap nut fails or is screwed on incorrectly.
WARNING: Immediately check for leaks when the boat is
placed in the water. Do not leave the boat unchecked for
more than three hours. Even a small leak may allow
considerable water to accumulate.
WARNING: Stainless steel housing in a metal hull—Be
sure the washer contacts the hull. Do not tighten the hull
nut with the washer against the isolation bushing, as the
housing will not be firmly installed.
CAUTION: Never pull, carry, or hold the sensor by its
cable. This may sever internal connections.
CAUTION: The arrow on the top of the insert must point
forward toward the bow to align with the water flow.
CAUTION: Plastic housing—Never use a fairing with a
plastic housing; the protruding sensor would be
vulnerable to damage from impact.
CAUTION: Metal housing—Never install a metal
housing in a vessel with a positive ground system.
CAUTION: Stainless steel housing in a metal hull—A
stainless steel housing must be isolated from a metal hull
to prevent electrolytic corrosion. Use the isolation
bushing supplied.
CAUTION: Never use solvents. Cleaner, fuel, sealant,
paint, and other products may contain solvents that can
damage plastic parts, especially the transducer's face.
CAUTION: Never power sand or pressure wash the
transducer. It may weaken the structure or damage the
internal components.
Retractable with Valve
Multisensor
®
Smart
™
& Installation INSTRUCTIONS
Record the information found on the cable tag for future reference.
Part No._________________Date___________Frequency________kHz
Sensor
IMPORTANT: Read the instructions completely before
proceeding with the installation. These instructions supersede any
other instructions in your instrument manual if they differ.

Applications

• Not recommended for boats designed to pull air under the hull.
• Best performance on a hull deadrise angle through 7°.
Accommodates up to a 22° deadrise angle.
• Plastic housing recommended for fiberglass or metal hull only.
Never install a plastic housing in a wood hull, since swelling of
the wood can possibly fracture the plastic.
• Bronze housing recommended for fiberglass or wood hull.
Never mount a bronze housing in a metal hull because
electrolytic corrosion will occur.
• Stainless steel housing compatible with all hull materials.
Recommended for a metal hull to prevent electrolytic corrosion
provided the stainless steel housing is isolated from the metal
hull.

How the Ultrasonic Speed Sensor Works

The speed sensor uses ultrasonic pulses to collect echoes from
small particles in the water as they pass under two transducers
embedded in the insert (Figure 1). These transducers monitor the
particles in their respective beams. As the boat travels through the
water, both transducers 'view' the same stream of particles.
Because it takes time for particles to travel between the two
transducers, the aft transducer detects the particles later than
does the fore transducer. By measuring this time lapse, the
instrument calculates the boat speed. If the boat is airborne, even
for a short time, or in highly aerated water, the sensor will
measure an incorrect speed.
vessel direction
particle stream
Figure 1. Monitoring particles in the water
scanning transducer
hull
FORE AFT
Copyright © 2002 Airmar Technology Corp.
plastic
low-profile
P617V housing