CS SR50A, Инструкция по эксплуатации

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Appendix D. RS-232 and RS-485 Operation
D-8
The frequency that the SR50A performs the measurement is set by adjusting
the Measurement Interval Units and the Measurement Interval Value
parameters.
• The main advantage of this operating mode is that the receiving device
will only have to wait 100 ms for the data instead of 1 second.
•
This configuration is also more conducive to a multidrop RS-485 system
where individual sensors do not transmit until they are addressed.
D.4.4 Distance to Target or Depth
The SR50A can output either distance to target values or calculate snow depth
values. To obtain a valid snow depth value the parameter distance to ground
must be entered in.
The SR50AT will compensate the readings for temperature.
Do not use this option on the SR50A sensor unless the SR50A is sent valid
temperature reading via the Temperature Input command.
D.4.5 Distance to Ground
A valid distance to ground must be entered when the SR50A is configured to
output snow depth values. The value must be in meters regardless of the output
units that are selected.
If the exact value cannot be obtained, it is better to slightly overestimate the
value rather than underestimating it. If a
Distance to Ground
value is too
small, the SR50A will output an error value as the snow surface should not be
below the ground surface.
D.4.6 Measurement Interval Units
This setting is only applicable if either the Auto Measure Polled Output or the
Auto Measure Auto Output modes are used. The options for the Measurement
Interval Units are:
•
Seconds
• Minutes
•
Hours
Once a unit type is selected, the number of units for the interval is set by
changing the Measurement Interval Value parameter. A 60 s interval can be
set by setting the units to seconds and the Measurement Interval Value to 60.
Alternately, the Measurement Interval Unit could be set to minutes and the
Value could be set to 1. The Value setting can only range from 1 to 255.
D.4.7 Measurement Interval Value
This setting is only applicable if either the Auto Measure Polled Output or the
Auto Measure Auto Output modes are used. The Measurement Interval Value
can range from 1 to 255. The units used for the value is set by the
Measurement Interval Units
.