Chassis

This section specifies the recommended chassis components and conditions for a system that includes NI DMMs.

PXI Chassis Recommendations

The NI PXI-4070/4071/4072 and NI PXI-4065 are designed to operate in any PXI-compliant chassis. Normal operating conditions for these DMMs include the following:

  • All PXI filler panels must be installed in empty slots.
  • The PXI chassis fans that provide forced air must remain unobstructed to allow for proper cooling of the PXI chassis, devices, and controller.
  • (Optional) Clean the chassis fan filters at least every six months. Some chassis include fan filters. Depending on the amount of chassis use and the ambient dust levels, filters might require more frequent cleaning. If regular maintenance of dirty or clogged filters is not possible, you can remove the filters to maintain adequate cooling.
  • Temperature rise on a module within a chassis can vary with slot position. You can keep this variation to a minimum by taking the precautions listed above.

PXI Express Chassis

Some PXI Express chassis provide hybrid slots. A hybrid slot can accept either PXI Express modules or PXI Express compatible modules, but not standard PXI modules. To determine if your chassis contains hybrid slots, refer to your chassis documentation. For more information about hybrid slots, refer to the related Web topic PXI Express FAQ.

Refer to PXI Express Compatibility, to determine if your DMM is PXI or PXI Express compatible and for more information about PXI Express compatibility.

PCI Chassis Recommendations

The NI PCI-4070 and NI PCI/PCIe-4065 are designed to operate in any ATX-compliant industrial or personal computer. Normal operating conditions for these DMMs include the following:

  • All covers for the industrial chassis or personal computer must be installed.
  • All PCI filler panels must be installed to close off unused PCI slots.
    Caution   For optimal electromagnetic compatibility (EMC) performance and input protection, you must install the front panel screw.
  • The PCI front panel bracket on the NI PCI/PCIe-4065 and NI PCI-4070 must have a firm, direct, metal-to-metal mounting connection to ensure proper grounding. Some computer manufacturers use a securing lever made of plastic; such a lever is unacceptable for safety reasons and must be removed. The PCI devices must be screwed down. If the chassis does not meet these requirements, you must use a different computer chassis.

The cooling capability in most industrial and personal computers is less effective than the cooling capability in a PXI chassis. The NI PCI/PCIe-4065 dissipates low enough power that additional cooling is not needed in most computers. The NI PCI-4070 dissipates higher power, and NI strongly recommends that NI PCI-4070 users implement the following precautions to maximize the cooling capability of the computer:

  • Install an additional 80 mm, 32 cubic ft/min (CFM) fan that forces air towards the NI PCI-4070. Most computer chassis contain one or two mounting locations for this type of fan. These fans are inexpensive and readily available at most computer supply stores.
    Note If the hard drive mounts vertically in front of the fan mounting location(s) in the computer chassis, you must move the hard drive to a horizontal 3.5 inch drive bay or to another suitable location that does not obstruct the fan mounting location(s).
  • Add additional fans, such as PCI fan cards and chassis fans, to increase the air circulation inside the computer.