The function of PXI extension card is to extend the PXI backplane signal outside of the chassis. Inserting the PXI card to extension card can easily check or measure the PXI card's signal under power on condition, which resolves the problems of inconvenient inspection due to the PXI card inside the chassis for RD or maintenance personnel. PXI extension card is able to isolate the voltage and signals sent to the PXI card for hot swap when the system is powered on. Every time the extension card activates it can supply the power required for PXI initialization. It eliminates the need for rebooting PC when users read and re-write the configuration files.

PXI extension card allows users to measure the voltage consumption power of PXI standard 5 sets voltage easily using the voltage meter. The extension card has over current protection circuit that can prevent the system backplane and other related components from damage once the PXI card malfunctions. Jumpers on the extension card are available for users to define the current range for protection; in addition an outward power connector is attached to supply the power externally instead of using the backplane power.