Ratio Measurement Procedure - Datron 1061A User Handbook Manual

Ratio
measurement procedure
The
ratio
of
any two
similar
function inputs
can
be
displayed
by
following the procedure
shown
above.
If
'Auto'
is
selected the
two
inputs
may
be of widely
different
magnitude, although
maximum
permiss-
ible
input voltages are limited to
250V
RMS
when
using the rear input
plugs.
The
display will
show
a value equal
to:
rear
inpu
t
x
100%
ratio input
An
Error
1
indicates
an
arithmetic
overflow
Error 9
indicates
an arithmetic
underflow
In either case, the rear or ratio input signal
should
be adjusted
until a valid ratio
reading
is
obtained.
Deselection of
this
mode
is
made
by repressing the
'Ratio' key.
Example
of
ratio
measurements
The
instrument's
AC
converter
is
a true
RMS DC
coupled
unit,
making
it
possible
to
perform
AC:
DC
ratio
measurements.
When
used
in this
way, with
an
AC
source
compared
with
an accurate
DC
source,
the
instrument
operates as
an automatic
AC/
DC
transfer
standard with a typical transfer
accuracy
of
0.01%
at
low
frequency.
Transfer standard
measurements should be
made
with
the
instrument set to take
DC
coupled
AC
measurements
(see
section
2).
Connect
the
AC
source
to
the rear
input plug
and
the
DC
source to
the ratio
input
plug, a displayed reading of
100%
indicates
an equalized
state.
Fig 3.2
Rear
and
ratio
inputs 7-pin plugs
Ratio
in
Average
Modes
Input
Filter.
The
associated
rolling
average
is
not
available
in 'Ratio'.
1071
Continuous
'Av\
The
1071
first
measures
the
two
inputs
and computes
the ratio
normally.
This
ratio
is
averaged with
all its
predecessors,
and
only
the
new
average
is
displayed.
1071
Block 'Av\
The
1071 takes a
full
block
of 'Ratio
Input'
measurements and
stores
their average.
It
then takes a
full
block of'Rear
Input'
measurements
and
stores their average.
The
ratio:
Rear
Input Average x 100%
Ratio Input Average
is
computed and
displayed.
3-2