Fluke 8845A, User Manual

Page: 73 / 103

Making Measurements
Measuring Voltage
4
4-5
is only available for dc functions at rates slower than 1 PLC. The
number of readings averaged by the digital filter varies with dc
function and range.
A FLTR
A 3-pole analog filter for improving noise immunity. The filter is
active when this soft key label is highlighted and will increase
stabilization time of the measurement. See Appendix D for more
information on when to use the analog filter.
Note
For best results, the filter may require zeroing the
function when used.
RATIO
DC measurement voltage divided by dc reference voltage. For dc
ratio, connect the reference HI/LO to the Meter’s HI/LO sense
terminals and the measurement voltage to the Meter’s HI/LO input
terminals. Note the specified measurement range applies to the input
terminals only.
Note
For best results in RATIO, the two input commons must
be shorted at the Meter terminals. The analog filter
(A FLTR) should be off.
2ND MEAS
Cycles the secondary display through the measurement functions
listed below, and then off. When a second measurement function is
selected, the
2ND MEAS
soft key label is highlighted.
VAC
- Displays the ac signal riding on the measured dc voltage.
Note
DCV/ACV dual mode should not be used at frequencies
below 20 Hz.
See the “Range Keys” section in Chapter 1 to learn how to switch between auto and
manual ranging.
Measuring AC Voltage
To make an ac voltage measurement:
1.
Press
A
.
The ac voltage icon V
B
will appear in display as shown below.
0.3 8 61
m V
~
F1 F2 F3 F4 F5
caw022.eps
2. Connect the test leads to the Meter’s input as shown in Figure 4-1.
3. Connect the test leads to the circuit and read the measured voltage in the Meter’s
display.