Logical Channels And Output Channels; Sdi-12 Bus - Adcon A850 User Manual

Logical Channels and Output Channels

SDI-12 Bus

Note: To find out which internal sensors your devices are
equipped with, please refer to the user manuals of the
respective devices.
Logical channels and output channel are used at the A740 RTU.
The A740 provides programmable sensor connections which are
combined as LC and OC connections.
Logical channels are used for analog/digital sensors.
Output channels are used for analog/digital actuators.
For details see the A740 user manual.
The abbreviation "SDI-12" is an acronym for "Serial Data Interface
with 1.200 baud". This standard communications protocol was
developed particularly to interface battery powered recording
devices with micro-processor based sensors designed for environ-
mental monitoring. Unlike RS-232/RS-485 devices which usually
require proprietary drivers for communication, the SDI-12 protocol
ensures compatibility between all sensors and loggers featuring
such an interface. If you want to learn more about SDI-12, visit the
website of the SDI-12 Support Group , "http://www.sdi-12.org/".
The SDI-12 bus built into the A740 addNODE or usable with an
adapter on A723 addITs and A733 addWAVEs is enjoying increas-
ing popularity with manufacturers of low power sensors, particu-
larly in the field of water quality monitoring. Many manufacturers
of multi-parameter probes, like Hydrolab, YSI and Greenspan,
already offer SDI-12 compatible probes.
Note: The A506 SDI-12 Adapter makes A723 addITs and A733
addWAVEs SDI-compatible. If you have SDI-12 sensors,
attach the SDI-12 adapter and the respective sensors. For
more details about installing the SDI-12 adapter and SDI-12
sensors, consult the corresponding users manuals.
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CHAPTER 4
Sensor Connections