User`s guide

261
Chapter 7 Tutorial
System Cabling and Connections
4
7
Sources of System Cabling Errors
Radio Frequency Interference Most voltage-measuring instruments
can generate false readings in the presence of large, high-frequency
signals. Possible sources of high-frequency signals include nearby radio
and television transmitters, computer monitors, and cellular telephones.
High-frequency energy can also be coupled to the internal DMM on the
system cabling. To reduce the interference, try to minimize the exposure
of the system cabling to high-frequency RF sources.
If your application is extremely sensitive to RFI radiated from the
instrument, use a common mode choke in the system cabling as shown
below to attenuate instrument emissions.
Tor r oid
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Modules
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