File name 182_901_02E.pdf
Model 182 Sensitive Digital Voltmeter
Instruction Manual Addendum
This manual addendum is being provided in order to supply you with the latest information in the least possible
time. Please incorporate these changes into the manual immediately.
Section 3, page 3-33, paragraph 3.12.4
Replace paragraph 3.12.4 with the following:
3.12.4 Electromagnetic Interference (EMI)
The electromagnetic interference characteristics of the Model 182 Sensitive Digital Voltmeter comply with the elec-
tromagnetic compatibility (EMC) requirements of the European Union (EU) directives as denoted by the CE mark.
However, it is still possible for sensitive measurements to be affected by external sources. In these instances, special
precautions may be required in the test setup.
Sources of EM1 include:
l Radio and TV broadcast transmitters.
l Communications transmitters, including cellular phones and handheld radios.
l Devices incorporating microprocessors and high-speed digital circuits.
l Impulse sources as in the case of arcing in high-voltage environments.
The Model 182, voltage source, and signal leads should be kept as far away as possible from any EM1 sources. Ad-
ditional shielding of the test fixture., signal leads, sources, and other measuring instruments will often reduce EMI
to an acceptable level. In extreme cases, a specially constructed screen room may be required to sufficiently attenu-
ate the troublesome signal.
The Model 182 digital filter may help to reduce EMI effects in some situations. In other cases, additional external
filtering may be required. Keep in mind, however, that filtering may have detrimental effects, such as increased set-
tling time, on the measurement.
182-901-02E / 11-95