SCXI-1521 Datasheet, PDF (1/3 Pages) National Instruments Corporation – 24 quarter-bridge strain gage inputs/Programmable excitation

SCXI Quarter-Bridge Strain Gage Input Module
NI SCXI-1521, NI SCXI-1521B
• 24 quarter-bridge strain gage inputs¹
• 350 Ω (SCXI-1521)
• 120 Ω (SCXI-1521B)
• Programmable excitation
(0 to 5 V) per channel
• Programmable shunt and null
calibration per channel
• 10 Hz filter per channel
• Onboard quarter-bridge completion
and shunt calibration resistors
• NI-DAQmx 7.3 simplifies
configuration and measurements
Operating Systems
• Windows 2000/NT/XP
Recommended Software
• LabVIEW
• LabWindows/CVI
• Measurement Studio
Other Compatible Software
• Visual Basic, C, C++
Measurement Services
Software (included)
• NI-DAQmx 7.3
Calibration Certificate Included
1_{For half-bridge or full-bridge strain gage}
measurements, please consider the SCXI-1520.
NEW
Overview
Null Compensation
The National Instruments SCXI-1521 and SCXI-1521B are quarter- Each input channel of an SCXI-1521/B includes a circuit to remove
bridge strain gage input modules that offer all of the features you need bridge offset voltage. Driver software nulls the offset voltage to zero
for high-channel-count applications. Each NI SCXI-1521/B is shipped in seconds. You do not need to manually adjust a potentiometer. By
with a NIST-traceable calibration certificate.
removing this offset through the measurement hardware, you can
Each SCXI-1521/B module can multiplex its signals into a single achieve better measurement resolution.
channel of the controlling DAQ device, and you can add more
modules to increase channel count.
Shunt Calibration
Analog Input
Each input channel of an SCXI-1521/B includes an accurate and
stable shunt calibration resistor with which you can progamatically
Each of the 24 analog inputs of the SCXI-1521/B consists of a simulate loading effects on your strain gage to compensate for
quarter-bridge completion resistor (350 Ω for the SCXI-1521 and strain gage errors. The shunt calibration resistors located inside of
120 Ω for the SCXI-1521B), and a 10 Hz, 2-pole Butterworth filter. the module. You enable or disable the shunt resistors through
You can program the excitation over 1024 different levels from 0 to software commands.
5 V. The 2-pole Butterworth filters provides lowpass filtering to block
noise and ensure measurement accuracy.
Measurement Services Software
Calibration
NI-DAQmx is the robust measurement services software included with all
National Instruments data acquisition and signal conditioning products.
The SCXI-1521/B modules provide simple yet powerful calibration This easy-to-use software tightly integrates the full functionality of your
capabilities. Each module has an onboard calibration EEPROM that DAQ hardware to LabVIEW, LabWindows/CVI, and Measurement Studio
stores calibration constants for each channel; factory calibration for Visual Basic. High-performance features include multidevice
constants are stored in a protected area of the EEPROM.
synchronization, networked measurements, and DMA data management.
NI-DAQ traditional and NI-DAQmx transparently use the Bundled with NI-DAQmx, the Measurement & Automation Explorer
calibration constants to correct for gain and offset errors for (MAX) utility simplifies the configuration of your measurement hardware
each channel.
with device test panels, interactive measurements, and scaled I/O channels.
NI-DAQmx also provides numerous example programs for LabVIEW
and other application development environments to get you started with
Terminal Block
SCXI-1317
Type
Screw terminals
CJ Sensor
–
Compatible Modules
SCXI-1521 & SCXI-1521B
Front-mounting
Cabling
–
Special Functions
–
Part Number
777687-17
your application quickly.
Table 1. Terminal Block Options for the SCXI-1521/B