YSI Level Scout - Manual (Page 40)

38 Level Scout YSI Incorporated
4.6 DESICCANT MAINTENANCE
Note – This maintenance procedure is not required for field cables that have the electrical in-line vent filter.
If using a cable with an external desiccant, it is recommended that you establish a regular replacement schedule for the desiccant. The
desiccant should be changed when it is 75% spent. Spent desiccant will have a pink color where unspent desiccant is light blue. The
frequency of the vent filter replacement will be a function of the local environment, particularly the humidity. Replacement filters
are available from YSI or any Authorized YSI Representative. Even if its color indicates it is spent, do not remove the old vent filter
until a new one is available. The desiccant vent filter will last at least one (1) year before replacement is necessary.
To replace the desiccant vent filter, use the following procedures:
1) Cut the nylon tie wrap securing the old vent filter to the cable assembly.
2) Disconnect the soft tubing of the old vent filter from the metal tube exiting the back of the 9-pin D-shell boot.
3) Immediately connect the soft tubing of the new vent filter onto the metal tube exiting the back of the 9-pin D-shell
boot.
4) When the transducer is placed back into service, remove the protective cap from the end of the vent filter.
Remember, the most common failure mode of vented transducers is moisture and corrosion damage due to lack of use or
maintenance of the vent filter.
4.7 DRYING THE TRANSDUCER CABLE
If water may have entered the cable vent tube or in the Level Scout, the following procedure can be used to dry either one out.
1) Remove the field cable assembly from the Level Scout.
2) If applicable, remove the desiccant from the cable.
3) Coil the cable then place it along with the transducer in a pan. Place the pan in an oven at 50
0 C (122 0 F) for a
minimum of two (2) hours. Ensure the oven temperature does not exceed 50 0 C (122 0 F). Temperatures above 50 0 C
(122 0 F) may damage both the transducer and cable.
4) If applicable, reattach the desiccant to the cable.
5) Reattach the cable to the transducer.
4.8 CLEANING THE TRANSDUCER
Either a clogged nose piece or a dirty transducer diaphragm could result in erroneous readings from the transducer. NEVER attempt
to clean the transducer’s nose piece or diaphragm with a sharp or hard object. To avoid damage to the diaphragm, NEVER insert a
sharp or hard object into the nose piece. This could dent the sensor diaphragm and cause permanent damage to the transducer
which is not covered under warranty. Use the following procedures to effectively clean the transducer:
Materials Required:
„ Plastic bowls 8-12 inches in diameter and 4-6 inches deep
„ Supply of clean, lint-free rags
„ 32 ounce bottle of “The Works-Tub and Shower Cleaner” a mild detergent, manufactured by Lime-O-Sol
Company and available at local stores.
Preparation:
Prior to cleaning the pressure transducer, ensure that the cable and the transducer body have been cleaned with a mild
detergent to remove any hazardous materials. If applicable, the vent filter must be properly attached. The cable should be
coiled to ensure ease of handling and it must be protected against the possibility of accidental abrasion and/or penetration
of the cable jacket by sharp objects. A lead length of 1 to 1½ feet of cable from the transducer should be allowed to facilitate
handling during cleaning. The protective dust cover (or similar protective device) that was shipped with the transducer
should be attached to the transducer at all times if the cable is not connected to the transducer.
The work surface needs to be clean, free of clutter, and large enough to accommodate all materials required in addition to
the transducer and cable. Fill one of the bowls with fresh water, one with a mild detergent mixed with water, and the last
with 16 ounces of “The Works.”