
Scans by ArtekMedia © 2007
The
Effect of Offset
on Scaling
SETUP CONDITIONS
TOTAL TIME
1.0
SECOND
RANGE
1
3.25
VOLTS
OFFSET 1 -2.05
VOLTS
The illustration below shows a recording area scaled for signal
A
(Channel
1
input) after using the range and offset values obtained from the
range and offset equations. Note that the plotted. signal uses the entire
Y-axis range.
-1.2
SET
RANGE'" y,IVm8K _Vmlnl
SET
'" 1'015.3
-H
.211vOl
TS
'" 3.25
VOLTS
OFFSET
'"
�
%
{VmilK
+
Vminl
,"-Y,{5.3�1.2IVOlTS
.. �2.05
VOLTS
-(OFFSET)
You may want to round the values for
Vmu
(round up) and
Vrnin
(round
down) so that the resulting range and offset values are whole numbers.
Rounding
Vmn
and
Vmin
results in a recording area with convenient
boundary values and provides some headroom for the recorded signal. This
is shown by the following illustration for a recording area prepared for
plotting signal
A
using rounded values for
Vmu
and
Vmin•
Note that the
preceding equations for detennining the offset Y-axis and boundary values
are still valid.
For versus-chan3 measurements, use the range and offset equations
to
detennine the appropriate range and offset settings for Channel 3. The
X-axis is scaled according to the Channel 3 settings in a manner identical
to the Y-axis of the versus-time examples given previously.
NOTE:
When using an offset setting that exceeds
±
full-scale range, in
accuracy of the indicated offset value can be up to ±3% of full-scale range
. •
3-14
Measurement Setup Operations
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