The NI 9237 C Series Strain/Bridge Input Module is a four-channel analog input module engineered for high-accuracy measurements of bridge-based sensors including load cells and torque transducers. Built on the CompactDAQ/CompactRIO platform, it delivers simultaneous sampling across all four channels with zero interchannel phase delay and integrated support for quarter, half, and full bridge configurations via four RJ50 connectors.
Technical Specifications
Analog Input Characteristics
• 4 simultaneous input channels with independent 24-bit delta-sigma ADCs
• Input range: ±25 mV/V
• Maximum sampling rate: 50 kS/s per channel
• Master timebase: Internal 12.8 MHz or external
• Data rate: fs = fM / 256 (n = 1 to 31)
Excitation Configuration
• Programmable excitation: 2.5 V, 3.3 V, 5 V, or 10 V
• Maximum internal excitation power: 150 mW
• External excitation supported with automatic power reduction
• Programmable bridge completion (internal for half/full bridge; external for quarter bridge)
Calibration & Measurement
• Offset/null calibration supported
• Shunt calibration via software-controlled switch and precision resistor
• Remote sensing for wiring resistance correction
• IEEE 1451.4 TEDS Class II support
Electrical Isolation
• 60 VDC Measurement Category I
• 1,000 Vrms transient isolation
• Channel-to-earth ground isolation: Up to 3,000 m (60 VDC continuous, 1,000 Vrms withstand); up to 5,000 m (60 VDC continuous, 860 Vrms withstand)
• Maximum safe voltage: ±30 V between any two pins
– Key Features
• Four RJ50 jacks for direct sensor connectivity
• 24-bit resolution with delta-sigma analog prefiltering
• Zero interchannel phase delay for synchronized measurements
• Operating temperature: -40 °C to 70 °C
• Vibration: 5 g; shock: 50 g
• Weight: 152 g (RJ50 connector version)
• Warning: RJ-45 cables incompatible with RJ50 connectors—risk of permanent damage
– Typical Applications
Structural health monitoring, fatigue testing, multiaxis load and torque measurement systems.
– Compatibility & Integration
C Series module compatible with CompactDAQ and CompactRIO chassis.
