www.vtiinstruments.com
EX1629 Basic Operation
43
S
ECTION
3
B
ASIC
O
PERATION
I
NTRODUCTION
This section expands on the description of the EX1629’s features and explains how to best use
them.
E
NGINEERING
U
NIT
(EU)
C
ONVERSION
Each EX1629 input channel can be individually configured for one of eleven different preset,
standard EU conversions. Each of these conversions is described below. Setting a specific
conversion not only controls the mathematical operations applied to the acquisition data, but also
automatically configures elements of the signal conditioning path. For example, setting a quarter-
bridge 350 conversion enables the 350 Ω completion resistor and connects the back-half resistors
to the +Sense measurement line, as illustrated in Figure 2-3. The automatic configuration,
however, can be overridden, as these elements can be configured independently.
Common terms used in the conversion equations are the following:
ε = strain
V
backhalf
= the voltage sensed from the back-half resistor network
V
-sense
= the voltage sensed on the –Sense input pin
V
+sense
= the voltage sensed on the +Sense input pin
V
unstrained
= the unstrained voltage (measured or manually entered)
V
excitation
= the excitation voltage (measured or manually entered)
GF = gage factor
ν = Poisson ratio
Quarter-Bridge 350, Quarter-Bridge 120, Quarter-Bridge User
These conversions apply to the following bridge configuration:
R
c om p
R ( )
g
V
OUT
V
EXC
+
–
+
–
R
R
F
IGURE
3-1:
Q
UARTER
-B
RIDGE
C
ONFIGURATION
The specific conversion is selected to match the nominal resistance of the active gage.
Содержание EX1629
Страница 310: ...VTI Instruments Corp 310 EX1629 Command Set...
Страница 342: ...VTI Instruments Corp 342 EX1629 Onboard Memory...