© National Instruments Corporation 2-1 SCXI-1503 User Manual
2
Connecting Signals
This chapter describes the input and output signal connections to the
SCXI-1503 module with the module front connector and rear signal
connector. This chapter also includes connection instructions for the
signals on the SCXI-1503 module when using the SCXI-1306 terminal
block.
In addition to this section, refer to the installation guide of the terminal
block for detailed information regarding connecting the signals. If you are
using a custom cable or connector block, refer to the Front Connector
section.

Analog Input Signal Connections

Each differential input (AI+ and AI–) goes to a separate filter and amplifier
that is multiplexed to the module output buffer. If the terminal block has a
temperature sensor, the sensor output—connected to pins A3 and/or A4
(CJ SENSOR)—is also filtered and multiplexed to the module output
buffer.
The differential input signal range of an SCXI-1503 module input channel
is ±10 V when using a gain of 1 or ±0.1 V when using a gain of 100. This
differential input range is the maximum measurable voltage difference
between the positive and negative channel inputs. The common-mode input
signal range of an SCXI-1503 module input channel is ±10 V. This
common-mode input range for either positive or negative channel input is
the maximum input voltage that results in a valid measurement. Each
channel includes input protection circuitry to withstand the accidental
application of voltages up to ±42 VDC powered on or ±25VDC
poweredoff.
Caution Exceeding the input damage level (±42 VDC powered on or ±25VDC powered
off between input channels and chassis ground) can damage the SCXI-1503 module, the
SCXIbus, and the DAQ device. NI is not liable for any injuries resulting from such signal
connections.