WCA January 2015

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Wire & Cable ASIA – January/February 2015
Technologynews
CALIBRATION in measurement
technology means establishing the
measurement deviations on the
measuring unit.
During the calibration no technical
intervention occurs at the measuring
instrument, as opposed to adjusting
where an instrument is set or adapted
to keep the errors as small as possible
or that the number of errors does not
exceed the error limits.
The official calibration of a measuring
unit is carried out according to the rules
and regulations of the examining
authority and the unit is marked with
the respective stamp. The examining
authority establishes whether the
measuring unit fulfils the respective
prerequisites.
The validity of a calibration period
follows practical requirements such as
manufacturer information, requirements
of quality standards or company
internal and customer-specific
regulations, rather than an official
calibration with a fixed time period
validity for use.
In order to be able to compare results
of measurement, it must be possible to
feed back information via a chain of
comparison measurements to a
national or international master. For
this purpose, the display of the unit in
use or the material representation must
be compared with the masters in one
or more stages. At each of these
stages a calibration is carried out with
a master which has been previously
calibrated with a higher-level master.
According to the ranking of the master
– of consumption or factory standards
via reference masters up to national
standards – there is a calibration
hierarchy of points to be carried out.
This extends from the in-house
calibrating laboratory through
accredited calibrating laboratories up
to the national metrological institute.
Different standards, regulations and
guidelines are valid for the expert
carrying out of calibrations. A unit must
fulfil basic requirements before it can
be calibrated. One must also be aware
of the physical conditions required in
order to carry out a calibration and
observe them. Rules for the calibration
of instruments are essential when a
company decides on adhering to a
specific norm or guideline or if it
produces a product whose production
is subject to legal regulations.
The benefits of a Zumbach measuring
unit include:
• Calibration and self-calibration
functions of ODAC® measuring
heads
• Measuring units are calibrated
using reference standards which
were certified by the federal office
for metrology ) or by
accredited laboratories. Each unit
is supplied with a detailed
calibration protocol
• A regular check for measuring
errors along with the corresponding
protocol can be carried out
according to the customer
requirements. The regularity of
these calibrations is dependent on
the customer-specific requirements
(internal regulations). Zumbach
recommends a check every 12 to
24 months
• All the measuring heads of the
ODAC® series have a
self-calibration function (Patent
DE3111356) which makes
subsequent regular calibration
superfluous, except when
exchanging components
All the relevant parameters for
accuracy are continuously monitored
by the measuring system and
automatically compensated when
required.
This is particularly important for
possible ageing effects of the scanner
motor or the possible long-term drift of
the measuring electronics.
Zumbach Electronic AG – Switzerland
Website:
Increasing accuracy
❍ ODAC® measuring unit with reference
calibration standards
Worldwide GER
GER SA, Belgium, is a supplier of
quality second hand wire and cable
machinery with worldwide activities.
One of its key activities is the
purchase and sale of straightening and
cutting machines for smooth and/or
ribbed wires.
The machines are available in “as-is”
condition as well as mechanically and
electrically reconditioned or with new
electrics.
Extensions of existing outlet tables or
new outlet tables in any required
length are also being offered.
Once a machine has undergone
thorough reconditioning the buyer is
invited to witness a test run prior to
shipment. Installation and comm-
issioning by GER’s staff is also
possible.
GER SA – Belgium
Website: