Product Calibration; The Artifact Calibration Process - Fluke 5730A Calibration Manual

Product Calibration

The Product uses internal check standards and measurement systems. As a
result, it can be completely calibrated in place to full specifications with a small
number of convenient, portable, environmentally-tolerant standards available
from Fluke Calibration. This procedure provides traceability for the ac and dc
voltage, resistance, and ac and dc current functions.
When manufactured, each Product is calibrated and thoroughly verified with
process metrology and calibration standards traceable to the International
System of units (SI) through well-recognized national metrology institutes. A
certificate of calibration that is accredited to ISO 17025 is included.
The calibration verification procedure is recommended every 2 years or as
required by established policies. This procedure ensures internal processes are
in control, and establishes parallel external traceability paths for internal functions
such as ac transfers that are never adjusted or corrected.

The Artifact Calibration Process

Artifact calibration is the historical name for a process which adjusts internal
references to external standards, and then uses those internal references to
calibrate all ranges and functions. Artifact calibration requires three external
standards or artifacts: 10 V, 1 Ω, and 10 kΩ. Environmentally-controlled internal
check standards provide the primary reference points. A stored table of
calibration constants defines additional reference points for controlling the output.
A semi-automated process that revises the stored table, makes traceable
calibrations and adjustments to the specified level of performance.
When finished with artifact calibration, but before the new constants are saved,
the Calibrator presents the proposed adjustments as ±ppm of range and
percentage change in specification for each range and function. A list of changes
can be sent to a computer through the serial port, USB device port, Ethernet port,
or the IEEE-488 port using the remote command: CAL_RPT? CHECK. Also on
completion of calibration, the Product shows the largest proposed change.
Artifact calibration can be completed as far as deriving and printing the proposed
adjustments without entering the calibration protection passcode. To save the
changes in non-volatile memory to adjust future outputs from the Product, enter
the passcode from the front panel or with a remote command. The passcode
entry menu is shown on the display when necessary.
Multifunction Calibrator
Product Calibration
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