VXI VT1422A, Руководство пользователя

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78 Programming the VT1422A & VT1529A/B for Remote Strain Measurement Chapter 3
Programming for Remote Strain Measurement
This programming section is focused exclusively on programming the
VT1422A and VT1529A/B for remote strain measurement. For more
general VT1422A programing see Chapter 4 “Programming the VT1422A
for Data Acquisition and Control”.
Power-on and *RST
Configuration
Some of the programming operations that follow may already be set after
Power-on or after an *RST command. Where these default settings coincide
with the configuration settings required, there is no need to execute a
command to set them. These are the default settings:
•
No channels defined in scan list.
•
Programmable SCPs configured to their Power-on defaults.
•
VT1529A/B input filters:
-- INPut:FILTer:FREQuency 10,(@ <all channels> )
-- INPut:FILTer:STATe ON,(@ <all channels> )
•
All analog input channels linked to the EU conversion for voltage.
•
ARM:SOURce IMMediate
•
TRIGger:SOURce TIMer
•
TRIGger:COUNt 1
•
TRIGer:TIMer .010 (10 ms)
•
FORMat ASC,7 (ASCII)
•
SENSe:DATA:FIFO:MODE BLOCking
•
The defaults for the STRain Subsystem when SENS:FUNC:STRain is
selected will be:
-- Unstrained voltage for all strain channels is assumed to be zero.
-- Gage factor for all strain channels is assumed to be 2.
-- Excitation voltage for all strain channels is assumed to be 1.0E6
(must be changed to actual value to make reasonable measurements).
•
The default for the VT1529A/B strain configuration switches is:
-- Full Bridge (FBEN) on all 32 Channels (SENS:STR:BRID FBEN).
-- Bridge output sensed.
Description of
Strain Measurement
This section describes the three ways to make strain measurements with the
VT1529A/B. It includes references to SCPI commands as well as command
sequences to perform the strain measurements described.
CALibration First
To make proper measurements, *CAL? and CAL:REMote? should have
been done first. Perform *CAL? and CAL:REMote? before making
important measurement runs or if the temperature of the instrument’s
environment has changed significantly. Remember, the accuracy
specifications given in Appendix A on page 419 depend on recent *CAL?
and CAL:REMote? operations.