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7. CALIBRATION
This instrument has been fully calibrated at the factory in accordance to our published
specifications. It has been calibrated with standards traceable to CNLA. You will find in
this manual a copy of the "Certificate of Calibration". It is recommended that you have this
instrument re-calibrated and a safety check done at least once per year. EXTECH
recommends you use "Calibration Standards" that are NIST traceable, or traceable to agencies
recognized by NIST to keep this instrument within published specifications.
End user metrology standards or practices may vary. These metrology standards determine
the measurement uncertainty ratio of the calibration standards being used. Calibration
adjustments can only be made in the Calibration mode and calibration checks or verifications
can only be made while operating in Test mode.
7.1 Calibration Initialization
Press and hold the calibration key on the rear panel with a pen, pencil, or small screwdriver
while powering ON the 7630. The 7630 enters calibration mode after the power on sequence
is complete. The Initial Calibration screen will appear as follows:
The Calibration screen is separated into three sections. The left half of the screen lists all of
the calibration points necessary for an accurate calibration of the instrument. The right half
of the screen is split into two smaller screens. The upper right section of the screen displays
meter and load information required to perform the selected calibration. The lower right
section of the screen contains prompts that will help guide you through the calibration process.
7.1.1 Selecting Specific Calibration points
When the calibration is initialized, the first calibration point is automatically selected. The
calibration is set up so that as each calibration point is completed the highlighted area will