Chapter 3 Adjustment Procedures; Introduction; Required Equipment - Agilent Technologies 3458A Calibration Manual

Chapter 3

Introduction

Required Equipment

Adjustment Procedures
This section contains procedures for adjusting the 3458A Multimeter. The
3458A uses closed-box electronic adjustment. No potentiometers or other
electro-mechanical adjustments are used and the complete adjustment is done
without removing any of the multimeter's covers. Only a voltage standard.
A resistance standard, a low-thermal short, and an AC signal source are
needed to perform all of the adjustments. This chapter contains the following
adjustment procedures.
1. Front Terminal Offset Adjustment
2. Rear Terminal Offset Adjustment
3. DC Gain Adjustment
4. Resistance and DC Current Adjustment
5. AC Adjustment
You must perform the adjustments in the order presented in this chapter. All
of the adjustments can be performed in approximately one hour (you must
allow 4 hours of warm-up time from the time power is applied to the
multimeter before performing any adjustments). Whenever adjusting the
multimeter, always perform the adjustments numbered 1 through 4 in the
above list. Adjustment number 5 (AC Adjustment) is required only once
every 2 years or whenever the 03458-60502 or 03458-66503 PC assembly
has been replaced or repaired. Product Note 3458A-3 in Appendix B
discusses the purpose of each adjustment in detail.
An Adjustment Record is located at the back of this chapter. You should
make photocopies of this record and complete the record whenever the
multimeter is adjusted. The record contains information such as the date,
which adjustments were performed, the calibration number, and the
multimeter's adjustment temperature. You can then file the adjustment
records to maintain a complete adjustment history for the multimeter.
You will need the following equipment to perform the adjustments:
•
A low-thermal 4-terminal short for the offset adjustments (this is
typically a bent piece of copper wire as shown in Figure 1).
•
10 VDC Voltage Standard--Fluke 732A or equivalent (for the DC Gain
Adjustment).
•
10 kW Resistance Standard--Fluke 742-10 K or equivalent (for the
Resistance and DC Current Adjustment).
•
AC Source-Agilent 3325A Synthesizer/Function Generator or
equivalent (for the AC adjustment).

Chapter 3 Adjustment Procedures

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