FLUKE-87-5 Fluke Electronics, FLUKE-87-5 Datasheet - Page 37
![DMM INDUSTRIAL TRUE-RMS W/TEMP](/photos/27/4/270406/fluke-87-5_sml.jpg)
FLUKE-87-5
Manufacturer Part Number
FLUKE-87-5
Description
DMM INDUSTRIAL TRUE-RMS W/TEMP
Manufacturer
Fluke Electronics
Series
8xr
Type
Digital (DMM)r
Specifications of FLUKE-87-5
Includes
Battery, Clips, Temperature Probe, Test Leads
Style
Handheld
Display Digits
4.5
Display Type
LCD, Bar Graph
Display Count
20000
Function
Voltage, Current, Resistance, Capacitance, Temperature, Frequency
Functions, Extra
Continuity, Diode Test
Features
Auto Off, Backlight, Clips, Hold, Min/Max/Ave
Ranging
Auto/Manual
Response
True RMS
Lead Free Status / RoHS Status
Vendor undefined / RoHS compliant by exemption
Other names
2074974
614-1042
87 V
87-5
87-V
FLUKE 87 V
FLUKE-87-V
614-1042
87 V
87-5
87-V
FLUKE 87 V
FLUKE-87-V
Measuring Duty Cycle
Duty cycle (or duty factor) is the percentage of time a
signal is above or below a trigger level during one cycle
(Figure 9). The duty cycle mode is optimized for
measuring the on or off time of logic and switching
signals. Systems such as electronic fuel injection systems
and switching power supplies are controlled by pulses of
varying width, which can be checked by measuring duty
cycle.
To measure duty cycle, set up the Meter to measure
frequency; then press Hz a second time. As with the
Trigger Point
+Slope
30% Above
+Slope
Figure 9. Components of Duty Cycle Measurements
-Slope
Trigger Point
100%
70% Below
-Slope
frequency function, you can change the slope for the
Meter's counter by pressing E.
For 5 V logic signals, use the 6 V dc range. For 12 V
switching signals in automobiles, use the 60 V dc range.
For sine waves, use the lowest range that does not result
in multiple triggering. (Normally, a distortion-free signal
can be up to ten times the amplitude of the selected
voltage range.)
If a duty cycle reading is unstable, press MIN MAX; then
scroll to the AVG (average) display.
Making Measurements
iy3f.eps
29