Fluke 5500A, Руководство по обслуживанию

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Calibration and Verification
Introduction
3
3-3
3-1. Introduction
Use this chapter as a guide to calibration and for verification of the 5500A’s
performance to specifications. You should recalibrate at the end of either a 90-day or
1-year calibration interval. If you recalibrate every 90 days, use the 90-day
specifications, which provide higher performance. Use the Verification procedure or any
part thereof any time you need to verify that the Calibrator is meeting its specifications.
3-2. Calibration
The standard 5500A has no internal hardware adjustments. The Oscilloscope Option has
hardware adjustments; see Chapter 7. All calibration is done with the covers on, using
software calibration constants. A calibration routine that prompts you through the entire
procedure is built into the 5500A. Calibration occurs in the following major steps:
1. The 5500A sources specific output values and you measure the outputs using
traceable measuring instruments of higher accuracy.
2. You enter the measured results either manually through the front panel keyboard or
remotely with an external terminal or computer.
3. The 5500A computes a software correction factor and stores it in volatile memory.
4. When the calibration process is compete, you are prompted to either store all the
correction factors in nonvolatile memory or discard them and start over.
For routine calibration, all steps except frequency and phase are necessary. All the
routine calibration steps are available from the front panel interface as well as the remote
interface (IEEE-488 or serial). Frequency and phase calibration are recommended after
instrument repair, and are available only by way of the remote interface (IEEE-488 or
serial). Remote commands for calibration are described at the end of this chapter.
3-3. Equipment Required for Calibration and Verification
The equipment listed in Table 3-1 is required to calibrate and verify performance of the
5500A. If a specified instrument is not available, you can substitute an instrument that
assures a 4:1 Test Uncertainty Ratio.