Campbell CR6 Series, Руководство оператора

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Section 7. Installation
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o SubScan() / NextSubScan introduces potential problems. These are
discussed in
SubScan() / Next Sub
(p. 215).
o SubScan() / NextSubScan Counts cannot be larger than 65535 .
o For SubScan() / NextSubScan to work, set Scan() / NextScan
Interval large enough for Counts to finish before the next
Scan()
/
NextScan
Interval .
7.7.14 Measurement: Excite, Delay, Measure
This example demonstrates how to make voltage measurements that require
excitation of controllable length prior to measurement. Overcoming the delay
caused by a very long cable length on a sensor is a common application for this
technique.
Measurement with Excitation and Delay
'This program example demonstrates how to perform an excite/delay/measure operation.
'In this example, the system requires 1 s of excitation to stabilize before the sensors
'are measured. A single-ended measurement is made, and a separate differential measurement
'is made. To see this program in action, connect the following terminal pairs to simulate
'sensor connections:
' U11 ------ U1
' U12 ------ U3
' U4 ------ Ground Symbol
'
'With these connections made, variables VoltageSE and VoltageDiff will equal 2500 mV.
'Declare variables.
Public VoltageSE As Float
Public VoltageDIFF As Float
'Declare data table
DataTable (Voltage,True,-1)
Sample (1,VoltageSE,Float)
Sample (1,VoltageDIFF,Float)
EndTable
BeginProg
Scan (5,sec,0,0)
'Excite - delay 1 second - single-ended measurement:
ExciteV (U11,2500,0) '<<<<Note: Delay = 0
Delay (0,1000,mSec)
VoltSe (VoltageSE,1,mV5000,U1,1,0,15000,1.0,0)