NI 9237 C Series Strain/Bridge Input Module – RJ50 Interface

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.