Hameg Instruments HZ530 Manual Del Usuario página 45

How important is EMC training?
How important is an instrument's amplitude accuracy?
Should pre-compliance instruments contain "CISPR bandwidths"?
How will the level of ambient signals affect my radiated emissions measu-
rements and will using fully compliant measuring equipment help?
Änderungen vorbehalten / Reservado el derecho de modificación
costly to implement. Pre-compliance instruments provide valuable
measurements and possess some of the features of compliance
equipment. Generally, though, precompliance instruments do not
need to conform fully to CISPR 16 and therefore can cost less.
Compliance equipment is your first choice if money is no object.
In reality, often you cannot justify the cost of such equipment and
need a more economical approach. Pre-compliance instruments
cost less and can provide useful measurements, but you must be
aware of the difference between the two types of equipment and
what you get as a measurement result. It is entirely possible to
make meaningless measurements with a US$50,000 CISPR-com-
pliant receiver. Equally, you can make valuable measurements with
a US$5,000 pre-compliance set-up.
EMC training is vital irrespective of whether you make compliance
or pre-compliance measurements. Much of the current debate re-
garding the two types of instruments is rooted in misconceptions
that arise because of lack of knowledge and training. Without proper
training you can make meaningless measurements irrespective of
the type of equipment you use.
An instrument's amplitude accuracy is important, but uncertainty
for the whole measurement is of equal importance. If total measu-
rement uncertainty is ±6dB, the additional uncertainty between a
±0.5dB receiver accuracy and a ±2dB spectrum analyzer accuracy
is small.
The significance of CISPR bandwidths depends if your objective is
full compliance or pre-compliance testing. Not all pre-compliance
equipment necessarily contains CISPR-compliant bandwidths.
The level of ambient signals that exist in your laboratory or at a
particular "open area test site" directly affects your ability to make
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