Campbell TB4, Instruction Manual

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TB4 and TB4MM Tipping Bucket Rain Gages
6
100
Ω
resistor is connected in series at the switch to prevent arcing by limiting
the current (FIGURE 7-1 ). This resistor is installed on all rain gages currently
sold by Campbell Scientific.
Black
White
Clear
100
Ω
FIGURE 7-1. Rain Gage Schematic
7.2 Datalogger Programming
Short Cut is the best source for up-to-date datalogger programming code.
Programming code is needed when:
•
Creating a program for a new datalogger installation
•
Adding sensors to an existing datalogger program
If your data acquisition requirements are simple, you can probably create and
maintain a datalogger program exclusively with
Short Cut . If your data
acquisition needs are more complex, the files that Short Cut creates are a great
source for programming code to start a new program or add to an existing
custom program.
Short Cut cannot edit programs after they are imported and edited
in CRBasic Editor .
A Short Cut tutorial is available in Section 4 , QuickStart
(p. 2)
. If you wish to
import Short Cut code into CRBasic Editor to create or add to a customized
program, follow the procedure in Appendix A , Importing Short Cut Code Into
CRBasic Editor
(p. A-1)
.
Programming basics for CRBasic dataloggers are in the following sections.
Complete program examples for select CRBasic dataloggers can be found in
Appendix
B , Example Programs
(p. B-1)
. Programming basics and programming
examples for Edlog dataloggers are provided at www.campbellsci.com\old-
manuals .
7.2.1 PulseCount Instruction
The TB4 uses a reed switch for measuring precipitation. The PulseCount()
instruction programs CRBasic dataloggers to measure the reed switch.
PulseCount (Dest,Reps,PChan,PConfig,POption,Mult,Offset)
•
Choose Switch Closure (code 2) for the PConfig parameter.
•
The Multiplier parameter determines the units in which rainfall is
reported. A multiplier of 0.01 converts the output to inches and a
multiplier of 0.254 converts the output to millimeters.
NOTE