Campbell Scientific CR510 Basic Datalogger User Manual
Page 158
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SECTION 13. CR510 MEASUREMENTS
13-14
FIGURE 13.4-2. Excitation and Measurement Sequence for 4 Wire Full Bridge
TABLE 13.4-1. Comparison of Bridge Measurement Instructions
Instr. # Circuit
Description
4
DC Half Bridge
The delay parameter
allows the user entered
settling time com-
pensate for capacitance
in long lead lengths. No
polarity reversal. One
single-ended measure-
ment. Measured
voltage output.
5
AC Half Bridge
Rapid reversal of
excitation polarity for
ion depolarization.
One single-ended
measurement at each
excitation polarity.
Ratiometric output.
6
4 Wire
One differential
Full Bridge
measurement at each
excitation polarity.
Ratiometric output.
Instr. # Circuit
Description
7
3 Wire
Compensates for lead
Half Bridge
wire resistance,
assuming resistance is
same in both wires.
Two single-ended
measurements at each
excitation polarity.
Ratiometric output.
8
Differential
Makes a differential
Measurement
measurement without
with Excitation
reversing excitation
polarity. Used for fast
measurements on load
cells, PRTs etc.
Resolution and common
mode rejection worse
than 6 if used with delay
= 0. Measured voltage
output.
9
6 Wire
Compensates for lead
Full Bridge
wire resistance. Two
or 4 Wire
differential measure-
Half Bridge
ments at each
excitation polarity.
Ratiometric output.