Rohde & Schwarz HMC8012G, Руководство пользователя

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General Information Regarding the CE Marking
General Informa-
tion Regar-
ding the CE
Marking
General Information Regarding the CE Marking
ROHDE & SCHWARZ measuring instruments comply with
regulations of the EMC Directive. ROHDE & SCHWARZ is
basing the conformity assessment on prevailing generic
and product standards. In cases with potentially different
thresholds, ROHDE & SCHWARZ instruments apply more
rigorous test conditions. Thresholds for business and com-
mercial sectors as well as small business are applicable
for interference emission (class 1B). As to the interference
immunity, the standard thresholds for the industrial sec-
tor apply. Measurement and data lines connected to the
measuring instrument significantly affect compliance with
specified thresholds. Depending on the respective appli
-
cation, utilized lines may differ. In regards to interference
emission and immunity during measurements, it is critical
that the following terms and conditions are observed:
1. Data Cables
It is imperative to only use properly shielded cables when
connecting measuring instruments and interfaces to exter-
nal devices (printers, computers, etc.). Unless the manual
prescribes an even shorter maximum cable length, data
cables (input/output, signal/control) may not exceed a
length of 3m and may not be used outside of buildings. If
the instrument interface includes multiple ports for inter-
face cables, only one cable at a time may be connected.
Generally, interconnections require double-shielded con-
necting cables. The double-shielded cable HZ72 (available
at ROHDE & SCHWARZ) is well suitable as IEEE bus cable.
2. Signal Cables
In general, measuring cables for the transmission of sig-
nals between measuring point and measuring instrument
should be kept as short as possible. Unless an even shorter
maximum cable length is prescribed, signal cables (input/
output, signal/control) may not exceed a length of 1m and
may not be used outside of buildings. All signal cables
must be shielded (coaxial cable RG58/U). It is important to
ensure proper ground connection. Signal generators re-
quire the use of double-shielded coaxial cables (RG223/U,
RG214/U).
3. Impact on Measuring Instruments
If strong high-frequency electric and magnetic fields are
present, it may occur despite diligent measurement setup
that unwanted signal units are injected into the measuring
instrument via connected measuring cables. This will not
damage the ROHDE & SCHWARZ measuring instrument
or put it out of operation. In some cases, these circum-
stances may cause the measuring value to slightly exceed
specifications.