Keithley SourceMeter 2425, Руководство по обслуживанию

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2-2 Calibration Model 2425 Service Manual
Introduction
Use the procedures in this section to calibrate the Model 2425. 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 The information in this section is intended for qualified service per-
sonnel only. Do not attempt these procedures unless you are qualified
to do so. Some of these procedures may expose you to hazardous volt-
ages.
Environmental conditions
Temperature and relative humidity
Conduct the calibration procedures at an ambient temperature of 18 to 28°C (65 to 82°F)
with relative humidity of less than 70% unless otherwise noted.
Warm-up period
Allow the Model 2425 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 manu-
facturer.
Line power
Model 2425 requires a line voltage of 100 to 240V at line frequency of 50 or 60Hz. The
instrument must be calibrated while operating from a line voltage within this range.