National Instruments SCXI -1122 Chapter 1 Introduction

Chapter 1Introduction

This chapter describes the SCXI-1122; lists the contents of your SCXI-1122 kit; describes the

optional software, optional equipment, and custom cables; and explains how to unpack the

SCXI-1122.

The SCXI-1122 has 16 isolated input channels and two isolated excitation channels. The

SCXI-1122 is a module for signal conditioning of strain gauges, RTDs, thermistors,

thermocouples, volt and millivolt sources, 4 to 20 mA current sources, and 0 to 20 mA process-

current sources. The SCXI-1122 can operate in two modes–two-wire scan mode with all 16

input channels used for input, or the four-wire scan mode with the eight upper channels

configured as sense leads for connecting inputs and the lower eight channels configured as

current output channels. The SCXI-1122 inputs are multiplexed to a single output, which drives

a single DAQ board channel.

The SCXI-1122 operates with full functionality with the National Instruments MIO-16,

Lab-PC+, and the SCXI-1200 boards. You can use the Lab and PC-LPM-16 boards with the

SCXI-1122, but these boards cannot scan the module. These boards can perform only single-

channel reads. You can multiplex several SCXI-1122s into a single channel, thus greatly

increasing the number of isolated analog input signals that you can digitize.

You can add the SCXI-1322 shielded terminal block, which has screw terminals to which you

can easily attach the input signals to the SCXI-1122. In addition, the SCXI-1322 has a

temperature sensor for cold-junction compensation of thermocouples. This cold-junction

reference (CJR) is multiplexed with the 16 input channels.

The contents of the SCXI-1122 kit (part number 776572-22) are listed as follows:

Kit Component Part Number

SCXI-1122 module 182366-01

SCXI-1122 User Manual 320516-01

If your kit is missing any of the components, contact National Instruments.

Detailed specifications of the SCXI-1122 are listed in Appendix A, Specifications.