National Instruments Module NI PXI-8250 User Manual

Also see for Module NI PXI-8250: Installation guide

Contents

National Instruments Module NI PXI-8250 User Manual Manual pdf 19 page image

Chapter 3 Hardware Overview© National Instruments Corporation 3-3 NI PXI-8250 User ManualSystem Monitoring ArchitectureWith the NI PXI-8250, you can simultaneously monitor intaketemperature, fan speeds, and power supply levels of your NI PXI chassis.This information allows the user to achieve a higher level of systemperformance reliability. Once the first set of data is processed, these statusparameters will also light up the top six LEDs on the front panel. The LEDslight either as green if the status parameter is in range, or red if theparameter is out of range. Refer to the Front Panel LEDs section for moreinformation on the LEDs.A custom FPGA on the NI PXI-8250 communicates with the power supplymodule of the chassis for status information. Upon boot-up, theNI PXI-8250 waits 7 seconds for the chassis sensors to acquire their firstvalue. Once the wait period is over, the NI PXI-8250 begins acquisition ofthe first full set of data from the chassis. The status information is thenobtained every 5 seconds automatically in hardware until the controller isrebooted or shutdown.Voltage Rail Level MonitoringThe NI PXI-8250 module monitors the +5 V, +3.3 V, +12 V, and –12 Vrails delivered by the power supply shuttle within an accuracy of ±100 mV.The data from the +5 V and +3.3 V rails have two significant figures, whilethe data from the +12 V and –12 V rails have one significant figure.Each power rail has its own status LED on the front panel to reflect thecurrent status of the rail. If the voltage rail is within ±5% of the commonchassis specification, then the LED will light green. Otherwise, the LEDwill light red.The voltage rail level monitoring feature of the NI PXI-8250 reports whena voltage rail goes out of spec. This information is useful in ensuring properoperating conditions for each PXI module.Temperature MonitoringThe NI PXI-8250 provides monitoring of the single intake thermistorlocated in the power supply shuttle of the PXI chassis. The reading from thethermistor (0–50 °C) is compared to the operating range of the chassis. Ifthe reading is in range, the TEMP LED will light green. Otherwise, it willlight red. All temperature measurements are reported in Celsius and areaccurate to within 1 °C of the actual intake temperature.