
O
PERATION
M
ANUAL
P
ROMO
®
2000
P
ALAS
®
G
MB
H,
M
ARCH
2010,
V
ERSION
V001032010
21
Each
measurement
result
is
being
falsified
by
imperfection
of
the
test
methods,
test
setups
and
devices,
by
environmental
and
monitoring
impacts,
sometimes
also
by
the
test
person’s
imperfec
‐
tion.
Also
the
time
changes
of
all
mentioned
error
sources
falsify
the
results.
There
are
to
be
differentiated:
methodic
errors
accidental
errors
gross
errors
5.1.1
Methodic
errors
Methodic
errors
can
arise
by:
Imperfection
of
the
measuring
devices
and
test
procedures
(e.g.
function
and
calibration
errors)
Neglected
impacts
(e.g.
pressure,
temperature
etc.)
Elektrical
and
magnetic
stray
fields
Lacking
pureness
of
the
substances
If
the
measurement
is
repeated
unter
the
same
conditions,
a
methodic
error
occurs
in
the
same
size
and
with
the
same
sign.
5.1.2
Accidental
errors
Accidental
errors
mainly
arise
by:
imperfection
of
the
human
sense
organs
unskilfulness
in
measuring
and
metering
outer
impacts
with
statistically
affect
(e.g.
vibrations,
variations
in
voltage
or
temperature
etc.)
Accidental
errors
have
a
statistic
character
and
possess
both
kinds
of
signs.
If
the
measurement
is
accomplished
several
times,
then
the
measured
values
strew
around
an
average
value.
5.1.3
A
gross
error
Using
an
unsuitable
test
equipment
is,
for
example,
a
gross
error.
Further
gross
errors
are
e.g.
de
‐
scribed
in
the
new
standards
and
guide
lines.
EN
779
The
correct
tolerance
indication
for
the
main
volume
flow
is
missing.
The
test
method
for
the
discharging
of
filter
media
in
this
standard
proposal
is
so
insufficient
that
we
regard
this
pro
‐