Description

NI  SCXI-1120D  8-channel isolated amplifier module

Isolation feature: Each channel is equipped with an independent isolation function. The working common-mode voltage between channels or between channels and ground is 250Vrms, which can effectively avoid electrical interference between input and output, enhancing the stability and anti-interference ability of the system.

Signal processing capability: It can amplify and isolate DC millivolt sources, voltage sources, 0 to 20mA, 4 to 20mA current signals, and thermocouple signals. The input range can be configured from ±5mV to ±10V via patch cords, and the amplifier gain can reach up to 1000, which can meet the processing requirements of various signals.

Filtering function: Each channel is integrated with a low-pass filter, which can be configured to 4.5kHz or 22.5kHz through jumper cables. This can effectively suppress high-frequency noise and make the output signal purer.
Module compatibility: It can be used in conjunction with the SCXI-1327 terminal block and can expand the input range of the module to ±250V. It can also be combined with devices such as the SCXI-1000 chassis to build a complete data acquisition system.
Calibration requirements: To ensure measurement accuracy, NI Company recommends a complete calibration of SCXI-1120D at least once a year. Calibration can also be carried out after use beyond the specified temperature range.

Specific application:
Shipborne dynamic parameter test In the shipborne weapon test system, the design is based on the PXI bus module. SCXI-1102B and SCXI-1120D are adopted as signal conditioning modules, combined with the PXI-6071E data acquisition module and the PXI-6608 counting/timer module, etc. The relevant dynamic parameters of the ship can be collected and adjusted to achieve accurate measurement of the parameters related to the operation status of the ship’s equipment.

Pressure signal acquisition system: In a certain pressure signal acquisition system, the SCXI-1120D module is used to conditioning the pressure signal. After the pressure signal is conditioned by SCXI-1120D, it is sent to the data acquisition module VXI-1433A or VXI-1564A through the backplane analog bus for A/D conversion. Finally, the main control machine performs conversion analysis, display and storage through the pressure measurement software, providing data support for the relevant pressure monitoring and analysis scenarios.

Integrated Test Platform for Microsatellites In the general microsatellite integrated test platform based on the PXI system, for the input of analog signals, the appropriate voltage is first selected through the terminal block, then isolated through the signal conditioning board (such as SCXI-1120D can be adopted), and finally sent to the A/D acquisition card to achieve the isolation between the satellite and the test system. Ensure the stability and accuracy of the signal during the testing process and guarantee the security of the system at the same time.

Thermocouple signal measurement: As the SCXI-1120D is suitable for the amplification and isolation of thermocouple signals, in some temperature measurement systems, the weak signals generated by the thermocouple can be connected to this module. By using its isolation function to avoid interference, by setting an appropriate gain to amplify the signal and then transmitting it to the data acquisition device, temperature-related parameters can be accurately measured.

Industrial current signal monitoring: In industrial production processes, for current signal monitoring scenarios of 0 to 20mA or 4 to 20mA, the SCXI-1120D module can be used. The module isolates the current signal to prevent it from being disturbed by external electrical interference. At the same time, it amplifies the signal as required to facilitate subsequent data collection and analysis, so as to monitor the operating status of industrial equipment or process parameters, etc.