Description

NI  SCXI-1121  4-channel universal input module

Channel characteristics: It features 4 independent channels, each of which can be independently configured with an isolation amplifier, filter, and excitation source. It can handle multiple signals simultaneously and can be reused as a single channel for a data acquisition (DAQ) device. Modules can also be added to increase the number of channels.
Signal input range: It can collect input signals such as strain, thermal resistance (RTD), thermocouple, millivolt, volt, 0 to 20mA and 4 to 20mA current. Each channel can be independently configured through patch cords, with an input range of ±2.5mV to ±5V. When using the gain of 1, the differential input signal range is ±10V, and the common-mode input signal range is ±10V.

Isolation feature: It has electrical isolation function and can provide working isolation of 250Vrms. It belongs to double insulation, category II, and can effectively protect the measuring equipment from electrical noise and potential hazards.
Filtering function: Each channel is equipped with a low-pass filter. The cut-off frequency can be selected as 4Hz or 10kHz through a jumper, which can effectively suppress high-frequency noise and make the output signal purer.

Output modes: There are two types, namely parallel output mode and multi-channel output mode. In the parallel output mode, the four input channels are connected in parallel to the four data acquisition board channels. In the multi-channel output mode, four channels are multiplexed onto one data acquisition board channel.

Other features: The module is equipped with an offset potentiometer, allowing users to manually calibrate each of the four channels. NI recommends calibrating once a year. Its maximum load resistance is 10kΩ. The operation requires the use of NI-DAQmx driver software. It can be programmed through software development environments such as LabVIEW or LabWindows/CVI. The module size is approximately 1.2×6.8×7.4 inches and the weight is 23.5 ounces.