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EX1629 Preparation for Use
31
Figure 2-4 illustrates how to connect two strain gages in basic half-bridge bending configuration.
As explained in
Maximizing Measurement Performance
in Section 1, the remote excitation sense
lines should ideally be used on the excitation source, connected at the same point that the
±Excitation lines are connected to the bridge. The shunt calibration lines (Pins 4 and 5), however,
are only necessary if that functionality is required. Note that the gage in tension is connected from
Pin 1 to Pin 3 and the gage in compression is connected from Pin 2 to Pin 3.
Furthermore, it is critical to understand how the EX1629 defines its measurement in this
configuration. Specifically, it defines the measured strain to be the strain that is present in each
gage, not the total of the two gages. For example, if the upper gage is subjected to tensile strain of
1000 µε and the lower gage is subjected to compressive strain of 1000 µε, the EX1629 will
measure a value of +1000 µε, not +2000 µε.
Strain
Bridge
8-pin telcom
connector (RJ-45)
350
120
User
10K
10K
+Excitation Sense
TEDS
COMM
External customer
shunt cal
resistor terminals
Internal
Rcal
55K
+ Excitation
- Excitation
Half-Bridge
(1 of 48 channels)
+Excitation
+Sense
-Sense
-R Cal
+R Cal
+Excitation Sense
-Excitation Sense
-Excitation
-Excitation Sense
RJ-45 Pin#
12345678
Pin 5
Pin 4
Pin 2
Pin 7
Pin 6
Pin 3
Pin 8
Pin 1
+
-
10K
10K
Instrumentation
Amplifier
+
-
x1
x10
x100
Hi
Lo
Shield
150
150
-Sense
-Cal
AGND
+Sense
Wagner
+Cal
AGND
430 kHz
LOW-PASS
FILTER
60.3 kHz
LOW-PASS
FILTER
ADC
TRIFILAR
FILTER
F
IGURE
2-4:
H
ALF
-B
RIDGE
C
ONFIGURATION
Figure 2-5 illustrates how to connect four strain gages in basic full-bridge bending configuration.
As explained in
Maximizing Measurement Performance
in Section 1, the remote excitation sense
lines should ideally be used on the excitation source, connected at the same point that the
±Excitation lines are connected to the bridge. The shunt calibration lines (Pins 4 and 5), however,
are only necessary if that functionality is required. Note that the gages in tension are connected
from Pin 1 to Pin 6 and from Pin 2 to Pin 3 and the gages in compression are connected from Pin 2
to Pin 6 and from Pin 1 to Pin 3.
Содержание EX1629
Страница 310: ...VTI Instruments Corp 310 EX1629 Command Set...
Страница 342: ...VTI Instruments Corp 342 EX1629 Onboard Memory...