Specifications

Section 7. Measurement Instructions
SW12 (SW12Channel, State)
The SW12 instruction is used to set a Switched 12-volt supply high or low.
The datalogger has two switched 12-volt outputs, each with two terminals.
This switched 12 volts is used to provide a continuous 12-volt supply to
external peripherals. At room temperature the switched 12-volt supply can
source 900 mA between the SW-12 terminal and Ground. The State parameter
indicates whether the switched 12 volts is High (non-zero) or low (0).
Each SW-12 supply is unregulated and can supply up to 900 mA
at 20C, up to 630 mA at 50C, and up to 360 mA at 85C. A
resettable polymeric fuse protects against over-current. Reset is
accomplished by removing the load or turning off the SW-12 for
several seconds.
NOTE
Parameter
& Data Type
Enter
SW12Channel
Alpha
Code
Code/
Channel
Result
SW12-1 1 Switched 12V channel 1 set according to State parameter
Constant
SW12-2 2 Switched 12V channel 2 set according to State parameter
Value Result
0 The SW-12 ports are switched off (0V)
State
Constant
Variable or
Expression
≠0 The SW-12 ports are switched On (Connected to supply voltage)
7.6 Self Measurements
Battery (Dest)
This instruction reads the battery voltage and stores it in the destination
variable. The units for battery voltage are volts.
Calibrate (Dest, Range)
The Calibrate instruction places the CR3000 self calibration under program
control. Placing the Calibrate instruction in the program disables the automatic
self calibration that is normally run in the background (Section 3.8).
Calibration is typically performed to compensate for errors in voltage
measurements due to temperature.
The Calibrate parameters are optional and are only used to place the results of
the calibration in a variable array. With no parameters the Calibrate instruction
does not return data.
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