PXIe-1075 Power switch will not turn off chassis

[JustinD]

Hi,

I think I am having trouble turning my PXIe-1075 chassis off with the front mounted power switch. When I press the power switch, the green LED will ficker and the PWR LED on my PXIe-8360 MXI card will flicker from green to red and then back to green. I have a PXI-1042 chassis as well that seems to turn off properly. The switch on my PXI-1042 chassis has two positions, but the switch on my PXIe-1075 only seems to have one position. I am in a spot where I will need to power off my chassis to move it occasionally. Does it sound like my PXIe-1075 chassis has an issue? Am I missing something? I also tried holding the power switch. This will cause all the installed modules active light to turn off, but the PWR light on the switch and the PWR light on the MIX card will stay the same.

[Air_Frantz]

Hello,

The 1075 has two modes for shutdown.  You can select between the modes with the 'inhibit' switch on the back of the chassis.  When this switch is in the default position, the chassis will power down when you shut down the controller in the chassis (I'm not sure if it will automatically power down with the MXI connection when you shutdown the PC- I do not believe it will).  When the switch is in the manual position, the chassis does not shut down with the controller and you must use the Inhibit signal on pin 5 of the Remote Inhibit and Voltage Monitoring connector.  I believe your chassis is in 'Manual' mode.  More information on this is available in the manual on page 2-12:

http://www.ni.com/pdf/manuals/372537b.pdf

I do not think that the power button on the front can be used to power off the chassis.

[JustinD]

I checked the switch to make sure it was in the default mode. The chassis still would not power down with front switch. I removed all the cards and used to the front switch to power up the chassis, and I was able to use the front switch to power it down as well. When I replaced my NI PXI-6552 module back in the chassis (hybrid slot), the isssue started again. I tried one other hybrid slot and the power down issue was the same. I believe it is my NI 6552 card since the issue only happens when it is installed.

[Robert__R]

It sounds like your chassis is okay.  Here's a summary of how the power control works in PXIe.

The chassis power button is routed to the controller slot (PXIe-8360 in this case).  When the controller decides power should be on, it asserts a signal (separate from the power button signal) to the backplane.  Other control logic may be merged at this point (such as the inhibit mode switch or over-temperature shutdown).  That eventually finds its way to the power supply control signals.  So the controller is normally in charge of the chassis power supplies.

A second piece of what's happening is probably the WAKE# signal on the backplane.  It's a signal that allows peripheral modules to wake the system (like wake on LAN).  There's a pullup on the controller card, and any peripheral card can pull the line low.

From your experiments, it sounds like either the MXI card is bad (maybe missing the pullup on WAKE#?) or the PXI-6552 is pulling that line low.  The WAKE# pin, D2 on the top connector, was redefined for PXIe.  It was local-bus right 2 for standard PXI, and it's WAKE# for PXI Express (or hybrid) slots.

- Robert