Fluke 289 - Manual (Page 36)

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Users Manual
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Measuring AC and DC Signals
The Meter is capable of displaying both ac and dc signal
components (voltage or current) as two separate readings or one
AC+DC (rms) value combined. As shown in Figure 13, the Meter
displays ac and dc combinations three ways: ac displayed over
dc (AC,DC), dc displayed over ac (DC,AC), and ac combined
with dc (AC+DC). Select one of these three displays using the
Function and Mode menu.
With the rotary switch set to U, N, A, or X, press the
softkey labeled Menu. Move the menu selector to the menu item
labeled AC+DC. At this point, three different softkey labels
indicate AC+DC (F1), AC,DC (F2), and DC,AC (F3). Press the
softkey that presents these two signals as needed.
While in any of the three AC+DC modes, peak measurements,
frequency, duty cycle, and period measurements are not
allowed. In addition to these modes, MIN MAX, relative, and
relative % are not allowed in AC,DC or DC,AC modes.
Note
The bar graph is not displayed while the Meter is in
any of the three AC+DC modes.
Menu
123.45
VAC
AC over DC DC over AC AC + DC
VDC
23.45
Save Setup
Auto Range
500 VAC
Menu
125.66
V
VDC
23.45
Save Setup
AC + DC
500 V
Menu
23.45
VDC
VAC
123.45
Save Setup
Auto Range
500 V
Auto Range
8:10pm 06/13/07 8:10pm 06/13/07 8:10pm 06/13/07
est30.eps
Figure 13. AC and DC Display
Both manual and autoranging is available when using the ac+dc
modes. The same range is used for both ac and dc signals.
However, while in autorange, up-ranging occurs when either the
ac or dc signal exceeds the present range. Down-ranging occurs