National Instruments NI-9235 C Series Strain/Bridge Input Module

The National Instruments NI-9235 (Part Number: 785995-01) is a Strain/Bridge Input Module from the C Series. This 8-Channel module comes with 120 Ω Quarter-Bridge Strain Gage and can acquire samples at 10 kS/s/channel. The NI-9235 can measure dynamic strain on each of its channels simultaneously.  This capability enables it for high-speed, synchronized measurements and makes it a viable solution for applications that require real-time comparison across various channels at a specific instant in time.

The National Instruments NI 9235 module has an input range of ±29.4 mV/V and is rated for up to 120 Ω measurements. With eight channels available, this device can easily be integrated into high-channel-count measurement systems for CompactRIO or CompactDAQ.  For increased safety and less common-mode noise, the NI-9235 offers up to 60 VDC isolation (continuous) and 1,000 Vrms transient isolation. The integrated overvoltage protection inhibits overvoltage between any two terminals and is set at ±30 V. The NI-9235 has built-in excitation and supplies the required output current to all eight channels at minimum resistance.  

Each of the eight channels on the NI-9235 comes equipped with an independent, 24-bit Analog-to-Digital converter (ADC) and input amplifier. This module operates in isolation from earth ground. However, the channels have no isolation in between; all the EXC terminals connect to a common excitation supply. The NI 9235 shunt calibration circuitry consists of a software-enabled switch and a precision resistor. Each channel has a separate, unique shunt calibration resistor that can operate independently.