Campbell CR9000, Instruction Manual

Page: 124 / 218

Section 7. Measurement Instructions
7-10
the measurement of the voltage drop across the full bridge, and V2 is the
measurement of the bridge output.
7.5 Excitation/Continuous Analog Output
Excite (ExSlot, ExChan, ExmV, SettlingTime)
This instruction sets the selected excitation output to a specific value.
Channels 1 through 6 are continuous analog output channels and will remain at
the excitation voltage set by the instruction unless a subsequent instruction
changes their voltage. Channels 7 through 16 are switched excitation
channels, they are switched to the excitation voltage for the time specified for
the Delay and then switched off.
Parameter
& Data Type Enter
BRIDGEFULL, BRIDGEFULL6W, EXCITE PARAMETERS
Dest
Variable or
Array
The Variable in which to store the results of the instruction. When Reps are used the results are stored in an
array with the variable name. An array must be dimensioned to have elements for all the Reps.
Reps
Constant
The number of repetitions for the measurement or instruction.
Range
The voltage range for the measurement.
Constant ± 5 Volt Analog Input Module ± 50 Volt Analog Input Module
Alpha
Code Numeric
Code Voltage
Range Alpha
Code Numeric
Code Voltage
Range
mV5000 0 ± 5000 mV V50 6 ± 50 V
mV1000 1 ± 1000 mV V10 7 ± 10 V
mV200 4 ± 200 mV V2 10 ± 2 V
mV50 5 ± 50 mV mV500 11 ± 500 mV
ASlot
Constant
The number of the slot that holds the Analog Input Module to be used for the measurement.
DiffChan
Constant
The differential channel number on which to make the first measurement. When Reps are used, subsequent
measurements will be automatically made on the following differential channels.
ExSlot
Constant
The slot that holds the Excitation Module for the measurement.
ExChan
Enter the excitation channel number to excite the first measurement.
Constant Channels Result
1 - 6 Continuous analog output channels, will remain at the excitation voltage set by the
instruction unless a subsequent instruction changes their voltage
7 - 16 Switched excitation channels, are switched to the excitation voltage for the
measurement and switched off between measurements.
MesPEx
Constant
The number of sensors to excite with the same excitation channel before automatically advancing to the next
excitation channel. To excite all the sensors with the same excitation channel, the number should equal the
number of Reps.
ExmV
Constant
The excitation voltage in millivolts. Allowable range ± 5000 mV. RevEx may be used to excite with both a
positive and negative polarity to cancel offset voltages.
RevEx
Option to reverse excitation to cancel offsets.
Constant Value Result
0 Excite only with the excitation voltage entered
1 A second measurement is made with the voltage polarity reversed.
RevDiff Option to reverse inputs to cancel offsets
Constant Value Result
0 Signal is measured with the high side referenced to the low
1 A second measurement is made after reversing the inputs