CS SR50A, Инструкция по эксплуатации

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B-1
Appendix B. Example Programs
B.1 SDI-12 Example Programs
TABLE B-1. Wiring for CR1000 and CR6 SDI-12 Example Programs
107-L Air Temperature Sensor Wiring
Wire Color Sensor Wire Description CR1000 Wire Channels CR6 Wire Channels
Black Voltage-excitation input VX1 U2
Red Analog-voltage output SE1 U1
Purple Bridge resistor lead
⏚ ⏚
Shield EMF shield
⏚ ⏚
SR50A-L Configured for SDI-12 Wiring
Wire Color Sensor Wire Description CR1000 Wire Channels CR6 Wire Channels
Red Power source 12V 12V
Green SDI-12 I/O C1 C1
White Not used G G
Black Ground G G
Shield Shield/Earth ground G G
B.1.1 CR1000 SDI-12 Program
CRBasic Example B-1. CR1000 SDI-12 Program
'CR1000
'This program contains a number of features not found in Short Cut.
'
'The initial distance value from the SR50A head to the ground is
'measured by setting the flag SR50A_MID to TRUE. Set this flag after
'installing the SR50A in the field. Setting this flag will initiate
'a measurement cycle and the resulting value stored as the initial
'distance. The initial distance is used to calculate snow depth.
'The PreserveVariables instruction is used to store the initial
'distance in non-volatile memory. If power is lost at the site the
'initial distance value will be restored.'
'A control flag is used to initiate the SR50A measurement cycle. This
'allows for manual control in the field to check distances without
'waiting for the correct time interval to occur. It is also used by
'the datalogger to initiate an automated measurement cycle.
'
'Every measurement cycle is composed of 11 individual measurements
'that are spatially sorted to eliminate any low or high values.
'One measurement is made with each scan. This program has a 10
'second scan rate so it will take 100 seconds to do all 11 scans or
'1 minute and 40 seconds.
'Declare Variables and Units
Public BattV : Units BattV = Volts 'CR1000 battery voltage