Model DMM7510 7½ Digit Graphical Sampling Multimeter Reference Manual
Section 3: Functions and features
DMM7510-901-01 Rev. B / May 2015
3-7
Calculations that you can apply to measurements
The Model DMM7510 allows you to apply the following math operations to the measurement:
•
mx+b
•
percent
•
reciprocal (1/X)
Math calculations are applied to the input signal after relative offset and before limit tests. For more
detail on the order of operations, see
(on page 4-15).
Math operations apply to the selected measure function. If you change the measure function, the
math operation for that function becomes active.
Changing math functions does not clear the reading buffer, which can result in mixed units in the
reading buffer. If you are graphing, this can cause
?
to be displayed in the Y-axis. Clear the reading
buffer to remove the mixed units.
mx+b
The mx+b math operation lets you manipulate normal display readings (x) mathematically according
to the following calculation:
mx + b = Y
Where:
•
m
is a user-defined constant for the scale factor
•
x
is the measurement reading (if you are using a relative offset, this is the measurement with
relative offset applied)
•
b
is a user-defined constant for the offset factor
•
Y
is the displayed result
When the mx+b math operation is active, the unit of measure for the front-panel readings is
X
and the
MATH indicator is displayed to the right of the measurement. You cannot change this units
designator.
Set the relative offset using mX+b
You can use the mX+b function to manually establish a relative offset value. To do this, set the scale
factor (m) to 1 and set the offset (b) to the offset value. Each subsequent reading will be the
difference between the actual input and the offset value.
