XLINK 500/100 Operations & Maintenance Manual page # 78
The available
Measurement Type
options are
Precip Accumulation
Precip Rate
SDI-12
Analog
Battery Voltage
Wind
Digital
Meta
Manual Entry
Internal Temp
Below are listed all the
Measurement Types
available.
9.3.2.
Measure Type: Precip Accumulation and Precip Rate
Connection: Terminal #12 TB/DIN#2 and Terminal #11 Ground
Precip Accumulation and Precip Rate are designed to measure the pulses from a tipping bucket
type rain gauge.
Precipitation accumulation is used to tally the total amount of precipitation since the station has
powered up. Count must be set to zero by the user when the station is installed. Counts persist
between power-ups.
Precipitation rate, unlike precipitation accumulation, measures the precipitation that has
occurred since the last measurement. So, if the measurement interval is 15 minutes, this
measurement will report the rainfall in the last 15 minutes only.
Multiple measurements can be set up with the same input. For example, if you wanted to know
the daily rainfall and the rainfall during the last hour, set up two measurements: one a
Precip
Rate
with an interval of one hour, and another as
Precip Rate
with an interval of one day.
Usually, a slope is applied to convert the counts from the tipping bucket into inches of rain. For
example, setting the
Slope
to 0.01 means that each tip of the bucket is 0.01”.
Precip readings are de-bounced for 4ms.
Notes on Precip Rate
Precipitation rate is computed as the current count minus the count at the last scheduled
measurement.
The first scheduled reading of precipitation rate is invalid, as it takes two readings
before the difference can be computed.
When the system is not running, it is not able to make sensible Precip Rate readings.
Forced (live) precipitation rate readings are unreliable. The rate will be computed over
the currently elapsed time and extrapolated over the rest of the interval.
Precip Accumulation Reset
XLink may be setup to automatically reset precip accumulation.