More about SDI-12
Overview
SDI-12 is a standard for interfacing data recorders with microprocessor based sensors.
SDI-12 stands for serial data interface at 1200 baud. SDI-12 is intended for applications
with the following requirements:
•
Battery powered operation with minimal current drain
•
Low system cost
•
Use of a single data recorder with multiple sensors on one cable
•
Up to 200 feet of cable between the sensor and a data recorder
SDI-12 has the following advantages:
•
It defines a standard way for a data recorder and sensor to communicate.
•
Unique and complex self-calibration algorithms can be done in the sensor itself.
•
Sensors can be interchanged without reprogramming the data recorder with
calibration or other information.
•
Power is supplied to sensors through the interface.
•
The use of a standard serial interface eliminates significant complexity in the
design of the data recorder.
•
Low cost, small sensors can be designed with SDI-12 compatibility.
•
SDI-12 data recorders interface with a variety of sensors.
•
SDI-12 sensors interface with a variety of data recorders.
•
Personnel trained in SDI-12 will have skills to work with a variety of SDI-12 data
recorders and sensors.
SDI-12 is used in water resource research and management, industry, government, and
agriculture. For example, the U.S. Geological Survey uses over 4000 SDI-12 sensors in
its data collection networks. SDI-12 sensors are available that measure the following:
•
bridge scour
•
conductivity
•
dissolved oxygen
•
distance
•
groundwater level
•
petroleum hydrocarbons in water
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pH
•
pressure
•
redox (ORP)
•
tank level
•
temperature
•
tide and sea state
•
turbidity
•
water velocity
•
weight of snow and ice on a snow pillow
•
wind speed and direction
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