SonTek/YSI Argonaut-XR Technical Manual - HydroScientific West

SonTek/YSI
6.7. Routine Maintenance
Under normal conditions, the Argonaut requires little maintenance for years of reliable
performance. Normal wear does not change instrument performance and the Argonaut never
requires re-calibration for velocity data. This section describes suggested routine maintenance
procedures.
Cleaning the transducers
Biological growth on the transducers does not affect velocity measurements, but can decrease
acoustic signal strength and reduce the effective measurement range of the Argonaut. Periodic
cleaning of the Argonaut transducers may be needed to maintain optimal performance in areas of
high biological activity.
Except for deep-water (titanium) systems, Argonaut transducers are encapsulated in an epoxy
that is impervious to damage from barnacles or other types of growth. To remove growth, simply
clean with a stiff brush. The transducer epoxy is very durable and cannot be easily damaged
except by direct impact.
Deep-water (titanium) Argonaut MD systems, made from titanium, use urethane for the
transducers instead of epoxy. These transducers are not as resistant to damage as the epoxy
transducers, and long-term barnacle growth can potentially damage the transducers. Fortunately,
deep-water applications typically have little biological growth. These transducers can also be
cleaned with a stiff brush, taking additional care not to scar the urethane during cleaning.
We recommend coating the transducers with anti-fouling paint for deployments in regions of
high biological activity (§6.9).
Cable Maintenance
The underwater cables used with the Argonaut are often the most vulnerable part of the system.
All standard SonTek cables use a durable polyurethane jacket that provides excellent long-term
wear and abrasion resistance. However, any underwater cable is susceptible to damage and
reasonable precautions should be taken. Inspect all Argonaut cables and connectors for damage
on a regular basis, and replace if necessary.
O-rings
All Argonaut housings use a dual (redundant) o-ring seal. All SonTek o-ring seals are designed
for full-ocean depth pressures, even if the housings and transducers have lower pressure ratings.
The o-rings will provide faultless performance as long as care is taken whenever the system is
opened. Whenever the housing is opened, clean and inspect all o-rings and o-ring surfaces;
replace o-rings when necessary. While the system is open, protect o-ring surfaces from scratches
or other damage. Spare o-rings are included in the Argonaut tool kit.
Condensation in Argonaut Housings
Moisture in the air can potentially damage Argonaut electronics if allowed to condense inside the
housing. All underwater housings include desiccant to absorb moisture. Whenever opening the
Argonaut housing, take care to minimize the exposure of the desiccant to humid air. If you
suspect the desiccant has been saturated, replace the packet before closing the housing (spare
desiccant is included in the Argonaut tool kit). When possible, purge the housing with a dry, inert
gas (Nitrogen, Argon) before closing.
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Argonaut Operation Manual Firmware Version 7.9 (May 1, 2001)