PXIe Chassis Calibration - Necessary or Waste of Time?

[GFSmith]

We have a PXIe-1095 chassis that houses an NI PXIe-8880 controller, PXIe-4080 DMM, PXIe-5160 Oscilloscope, and 15 other PXIe modules.  There are a total of 18 PXIe modules installed in this chassis and it is connected to two other PXIe chassis that are also stuffed with equipment.

According to NIMax, the calibration for this chassis expired 1-Sept.-2021 and I have a copy of NI's calibration procedures for the PXIe-1095 (attached).  There is a 10MHz OCXO (Oven Controlled Crystal Oscillator) with a very tight accuracy spec. (+/-80E-9Hz).

What are the potential side effects if we don't get this unit calibrated?

[crossrulz]

If you are using the reference clock, you will have timing issues as the clock drifts over time.  If you are not using the reference clock, you will see no changes.

[santo_13]

Some instruments such as PXIe-657x do not have an onboard clock and rely on the PXIe_CLK100 for all its timing requirements.

If your chassis clock is uncalibrated, then the timing accuracy of such instruments are also affected subsequently.