![Campbell SR50AT Скачать руководство пользователя страница 28](http://html1.mh-extra.com/html/campbell/sr50at/sr50at_instruction-manual_488987028.webp)
SR50AT-Series Sonic Ranging Sensors
16
SDI-12
Command
Command Function/Description
Values Returned
aXT;CC.CC!
Extended
command
Provide the SR50A with a temperature value to perform
onboard temperature compensation. The temperature must
be in degrees Celsius with a maximum of seven characters
including sign and decimal.
a
Address is returned
aR0!
Returns the distance to ground setting in the SR50A. The
units returned are in met
re
s.
DG
aR1!
Returns the distance to ground setting in the SR50A. The
units returned are in inches.
DG
aR2!
Returns the temperature sent to the SR50A for internal
temperature compensation. This value remains the same
unless power is cycled or a new temperature values is sent.
T
Where a = address of SDI-12 device.
Where n = numbers 1 to 9
9. Maintenance and Troubleshooting
The SR50AT’s electrostatic transducer requires equal pressure on both sides.
Vent holes in the transducer housing are used to equalize pressure. Desiccant
(pn
#
4091) placed inside the transducer housing helps prevent condensing
humidity. Regularly inspect the desiccant and, if required, replace it. Desiccant
capable of absorbing moisture is blue. Once the desiccant becomes saturated,
the color changes from blue to pink. In humid environments, replace the
desiccant more frequently. Inspection or replacement of the desiccant requires
the SR50AT to be disassembled (Section
).
Replace the transducer assembly every three years if it is not in a humid
environment. Replace the transducer housing assembly every year in humid
environments.
•
Standard SR50AT housing and maintenance kit: pn
#
19486.
•
SR50AT open-faced housing and maintenance kit (used with the
SR50AT-316SS model): pn
#
32570.
•
SR50ATH housing and maintenance kit: pn
#
32571.
9.1 Disassembly/Assembly Procedures
FIGURES
show the procedure for disassembling the SR50AT.
Disassembly is required to inspect or replace the desiccant, and to change the
transducer and the option jumpers.
Before proceeding with any maintenance, always retrieve
the data first. Campbell Scientific also recommends saving
the datalogger program.
Always disconnect the SR50AT from the datalogger or the
connector before disassembling.
CAUTION
CAUTION