Hameg Instruments HM8040-3 Manuel page 16

G e n e r a l r e m a r k s r e g a r d i n g t h e C E m a r k i n g
General remarks
regarding the CE marking
HAMEG measuring instruments comply with the
EMI norms. Our tests for conformity are based upon
the relevant norms. Whenever different maximum
limits are optional Hameg will select the most
stringent ones. As regards emissions class 1B
limits for small business will be applied. As regards
susceptability the limits for industrial environments
will be applied.
All connecting cables will influence emissions as
well as susceptability considerably. The cables
used will differ substantially depending on the
application. During practical operation the
following guidelines should be absolutely observed
in order to minimize EMI:
1. Data connections
Measuring instruments may only be connected to
external associated equipment (printers, com-
puters etc.) by using well shielded cables. Unless
shorter lengths are prescribed a maximum length
of 3 m must not be exceeded for all data inter-
connections (input, output, signals, control). In case
an instrument interface would allow connecting
several cables only one may be connected.
In general, data connections should be made using
double-shielded cables. For IEEE bus connections
the double-shielded HAMEG cables HZ72S and
HZ72L are suitable.
2. Signal connections
In general, all connections between a measuring
instrument and the device under test should be
made as short as possible. Unless a shorter length
is prescribed a maximum length of 3 m must not
be exceeded, also, such connections must not leave
the premises.
All signal connections must be shielded (e.g. coax
such as RG58/U). With signal generators double-
shielded cables are mandatory. It is especially
important to establish good ground connections.
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Subject to change without notice
3. External influences
In the vicinity of strong magnetic or/and electric
fields even a careful measuring set-up may not be
sufficient to guard against the intrusion of
undesired signals. This will not cause destruction
or malfunction of HAMEG instruments, however,
small deviations from the guranteed specifications
may occur under such conditions.
HAMEG GmbH