Keithley SourceMeter 3A 2420, Руководство по обслуживанию

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2-2 Calibration
Introduction
Use the procedures in this section to calibrate the Model 2420. These procedures require
accurate test equipment to measure precise DC voltages and currents. Calibration can be performed
either from the front panel or by sending SCPI calibration commands over the
IEEE-488 bus or RS-232 port with the aid of a computer.
WARNING This information in this section is intended for qualified service personnel
only. Do not attempt these procedures unless you are qualified to do so.
Some of these procedures may expose you to hazardous voltages.
Environmental conditions
Temperature and relative humidity
Conduct the calibration procedures at an ambient temperature of 18-28°C (65-82°F) with rel-
ative humidity of less than 70% unless otherwise noted.
Warm-up period
Allow the Model 2420 to warm up for at least one hour before performing calibration.
If the instrument has been subjected to temperature extremes (those outside the ranges stated
above), allow additional time for the instrument’s internal temperature to stabilize. Typically,
allow one extra hour to stabilize a unit that is 10°C (18°F) outside the specified temperature
range.
Also, allow the test equipment to warm up for the minimum time specified by the manufacturer.
Line power
The Model 2420 requires a line voltage of 90 to 250V at line frequency of 50 to 60Hz. The
instrument must be calibrated while operating from a line voltage within this range.