Campbell Scientific CR5000 Measurement and Control Module - Manual (Page 133)

Section 7. Measurement Instructions
7-7
Half Bridge Parameters
Parameter
& Data Type Enter
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
Constant
Alpha Code Numeric
Code Voltage
Range
mV5000 0 ± 5000 mV
mV1000 1 ± 1000 mV
mV200 2 ± 200 mV
mV50 3 ± 50 mV
mV20 4 ± 20 mV
AutoRange 5 mV20 - mV5000 Selects range (Sect. 3.1)
mV200C
mV50C
mV20C
20
30
40 ± 200 mV
± 50 mV
± 20 mV
The mV200C, mV50C, and mV20C
ranges pull the channel into common
mode range and check for open input
SEChan
Constant
The single-ended channel number on which to make the first measurement. When Reps
are used, subsequent measurements will be automatically made on the following single-
ended channels. If the channel is entered as a negative number, all reps occur on that
channel.
ExChan Enter the excitation channel number to excite the first measurement.
Constan Alpha
Code Code/
Channel Result
VX1 1 Switched excitation channels, are switched to the excitation
voltage.
VX2 2 for the measurement and switched off between measurements.
VX3 3
VX4 4
MeasPEx
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 Code Value Result (Reversing requires twice as much time to complete)
Constant False 0 Excite only with the excitation voltage entered
True ≠0 A second measurement is made with the voltage polarity
reversed to cancel offsets
RevDiff Code Value Result (Reversing requires twice as much time to complete)
Constant False 0 Signal is measured with the high side referenced to the low
True ≠0 A second measurement is made after reversing the inputs to cancel
offsets