National Instruments NI PXI-8250 Front Panel Connector

Chapter 3 Hardware Overview

There are 6 system status LEDs to report the status of the +5V, +3.3 V,

+12 V, and –12 V power rails, the intake temperature of the chassis, and the

overall status of the power shuttle fans of the chassis. These LEDs only

light up either red or green depending on whether the status information

shows the parameters in the specified range. The criteria for the system

status LEDs to light green is provided in Table3-1. The acceptable range

for voltage rail data is ±5%, 0–50 °C for the intake temperature reading,

and 1500+ RPM for fan speed. Any data acquired outside of these ranges

will be reflected as a red-lit LED.

The 6 user LEDs are driven by implementing them in software. Refer to the

NISystem Monitor 1.1 Help for more information on developing

applications for the NI PXI-8250.

Front Panel Connector

The NI PXI-8250 has one 8-pin connector on the lower section of the front

panel. The 8-pin connector provides the three connections for the relay, as

well as five connections for the fused power outputs. The three relay pins

included normally closed (NC), normally open (NO), and common (COM)

ports to the electromechanical relay. The five power output connections

include fused pins to +5V, +3.3V, +12V, –12V, and ground.

Caution Power off all devices before connecting or disconnecting the NI PXI-8250 plug.

Failure to do so may damage the module.

Table 3-1. System Status LED Green State Criteria

Parameter Criteria for Green LED status

+5 V rail ±5% from nominal

+3.3 V rail ±5% from nominal

+12 V rail ±5% from nominal

–12 V rail ±5% from nominal

Fans >1500 RPM for all fans

Temperature 0–50 °C