Campbell Scientific SR50A Distance Sensor - Manual (Page 26)

SR50A Sonic Ranging Sensor
It is recommended that the transducer housing assembly (part number 19486 –
Transducer Maintenance Kit) be replaced every 3 years.
If the SR50A is used in an environment with high humidity, it is recommended
that the transducer housing assembly be replaced every year.
6. Disassembly/Assembly Procedures
It is important to follow these instructions to disassemble the SR50A.
Disassembly is required to change the transducer and the Option jumpers, and
to inspect or replace the desiccant.
Before proceeding with any maintenance on a data acquisition system, always
retrieve the data first. It is also recommended that the datalogger program be
saved.
If the sensor is in operation, always disconnect the SR50A from the datalogger
or the connector before disassembling. Refer to Section 3.4.1 or Section 3.5.1,
Wiring for further information on your specific wiring connection and
disconnection.
FIGURE 7. Disconnect Cable from Sensor
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