Operator`s manual

SECTION 9. INPUT/OUTPUT INSTRUCTIONS
9-4
PARAM. DATA
NUMBER TYPE DESCRIPTION
01: 2 Repetitions
02: 2 Range code
03: 2 Input channel number for
first measurement
04: 2 Excitation channel
number
05: 4 Excitation voltage
(millivolts)
06: 4 Input location number for
first measurement
07: FP Multiplier
08: FP Offset
Input locations altered: 1 per measurement
*** 6 FULL BRIDGE ***
FUNCTION
This instruction is used to apply an excitation
voltage to a full bridge (Figure 13.5-1), make a
differential voltage measurement of the bridge
output, reverse the excitation voltage, then
repeat the measurement. The result is 1000
times the ratio of the measurement to the
excitation voltage. A 1 before the excitation
channel number (1X) causes the channel to be
incremented with each repetition.
PARAM. DATA
NUMBER TYPE DESCRIPTION
01: 2 Repetitions
02: 2 Range code
03: 2 Input channel number for
first measurement
04: 2 Excitation channel
number
05: 4 Excitation voltage
(millivolts)
06: 4 Input location number for
first measurement
07: FP Multiplier
08: FP Offset
Input locations altered: 1 per measurement
*** 7 THREE WIRE HALF BRIDGE ***
FUNCTION
This instruction is used to determine the ratio of
the sensor resistance to a known resistance
using a separate voltage sensing wire from the
sensor to compensate for lead wire resistance.
The measurement sequence is to apply an
excitation voltage, make two voltage
measurements on two adjacent single-ended
channels, the first on the reference resistor and
the second on the voltage sensing wire from the
sensor (Figure 13.5-1), then reverse the
excitation voltage and repeat the
measurements. The two measurements are
used to calculate the resulting value, which is
the ratio of the voltage across the sensor to the
voltage across the reference resistor. A 1
before the excitation channel number (1X)
causes the channel to be incremented with each
repetition.
PARAM. DATA
NUMBER TYPE DESCRIPTION
01: 2 Repetitions
02: 2 Range code for both
measurements
03: 2 Input channel number for
first measurement
04: 2 Excitation channel
05: 4 Excitation voltage
(millivolts)
06: 4 Input location number for
first measurement
07: FP Multiplier
08: FP Offset
Input locations altered: 1 per measurement
*** 8 DIFFERENTIAL VOLTAGE WITH ***
EXCITATION AND DELAY
FUNCTION
This measurement consists of applying a single
excitation voltage, delaying a specified time, and
making a differential voltage measurement. If a
0 delay is specified, the inputs are not switched
for a second integration as is normally the case
with a differential measurement (Section 13.2).
The result stored is the voltage measured. With
a delay of 0 Instruction 8 does not have as good
resolution or common mode rejection as the
ratiometric bridge measurement instructions. It
does provide a very rapid means of making
bridge measurements as well as supplying
excitation to circuitry requiring differential
measurements. This instruction does not
reverse excitation.