OBS501 Smart Turbidity Meter with ClearSensor
®
Technology
15
Programming basics for CRBasic dataloggers are provided in the following
sections. Complete program examples for select CRBasic dataloggers can be
found in Appendix
(p. B-1)
. Programming basics and
programming examples for Edlog dataloggers are provided at
www.campbellsci.com/old-manuals
7.4.1 SDI-12
The
SDI12Recorder
instruction is used to read the OBS501 in SDI-12 mode.
When using a CR200(X), the
SDI12Recorder
instruction has the following
form:
SDI12Recorder
(Destination, Output String, Multiplier, Offset)
For the other CRBasic dataloggers, the
SDI12Recorder()
instruction has the
following form:
SDI12Recorder
(Destination, SDIPort, SDIAddress, “SDICommand”,
Multiplier, Offset)
Refer to Appendix
(p. B-2)
, for an example of
using this CRBasic instruction. More information about using the SDI-12
protocol is provided in Section
(p. 21)
, and Appendix
(p. D-1)
.
7.4.2 RS-232
The
SerialOut()
instruction sends strings over the Tx COM port and the
SerialIn()
instruction receives strings from the Rx COM port.
Refer to Appendix
(p. B-3)
, for an example of
using these CRBasic instructions. More information about using the RS-232
protocol is provided in Section
(p. 23)
.
7.4.3 Analog
The
PortSet
instruction is used to open the shutter. Either the
VoltDiff
(recommended) or
VoltSe
instruction is used to measure the analog voltage
output.
Refer to Appendix
(p. B-4)
, for an example of
using these CRBasic instructions.
7.5 Mounting Suggestions
Maximum depth for the OBS501 housing is 100 meters.
Schemes for mounting the OBS501 will vary with applications; however, the
same basic precautions should be followed to ensure the unit is able to make a
good measurement and that it is not lost or damaged.
•
The most important general precaution is to
orient the unit so that the
OBS sensor looks into clear water
without reflective surfaces. This
includes any object such as a mounting structure, a streambed, or
sidewalls. The backscatter sensor in the OBS501 can see to a distance of
about 50 cm (20 in) in very clean water at angles ranging from 125° to
