Fluke 80 Series III user manual Measuring Frequency

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Making Measurements

Measuring Frequency

Frequency is the number of cycles a signal completes each second. The meter measures the frequency of a voltage or current signal by counting the number of times the signal crosses a threshold level each second.

Table 7 summarizes the trigger levels and applications for measuring frequency using the various ranges of the meter’s voltage and current functions.

To measure frequency, connect the meter to the signal source; then press F. Pressing Tswitches the trigger slope between + and -, as indicated by the symbol at the left side of the display (refer to Figure 8 under "Measuring Duty Cycle"). Pressing Istops and starts the counter.

The meter autoranges to one of five frequency ranges:

199.99Hz, 1999.9 Hz, 19.999 kHz, 199.99 kHz, and greater than 200 kHz. For frequencies below 10 Hz, the display is updated at the frequency of the input. Between

0.5Hz and 0.3 Hz, the display may be unstable. Below

0.3Hz, the display shows 0.000 Hz.

The following are some tips for measuring frequency:

∙If a reading shows as 0 Hz or is unstable, the input signal may be below or near the trigger level. You can usually correct these problems by selecting a lower range, which increases the sensitivity of the meter. In the L function, the lower ranges also have lower trigger levels.

∙If a reading seems to be a multiple of what you expect, the input signal may be distorted. Distortion can cause multiple triggerings of the frequency counter. Selecting a higher voltage range might solve this problem by decreasing the sensitivity of the meter. You can also try selecting a dc range, which raises the trigger level. In general, the lowest frequency displayed is the correct one.

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Contents Series Lifetime Limited Warranty Table of Contents Series List of Tables Series List of Figures Series Introduction Series International Electrical SymbolsSafety Information Your Meter’s Features TerminalInputs Description Rotary Switch Positions Function Switch PositionPushbuttons Button Function Button FunctionButton Display Features Model 87 Shown Number Feature Display Features Indication100 ms ΜA, mA ΜF, nF Me, ke Hz, kHz, MHz Display Features NumberAutomatic Power-Off Power-Up OptionsInput Alert Feature Making MeasurementsMeasuring AC and DC Voltage Switch Box Testing for Continuity For in-circuit tests, turn circuit power off Measuring Resistance Isolating a Resistor DisconnectMeasuring Capacitance Using Conductance for High Resistance or Leakage TestsMeasuring Capacitance Series Testing a Diode Testing DiodesMeasuring AC or DC Current WWarningCurrent through one component Series Measuring Frequency All ranges Components of Duty Cycle Measurements Measuring Duty CycleAnalog Bar Graph Determining Pulse WidthModel 87 Bar Graph Models 83 and 85 Bar Graph 2 Digit Mode ModelMIN MAX Recording Mode MIN MAX Functions Touch Hold Mode Relative ModeZoom Mode Models 83 Maintenance Uses for the Zoom Mode Models 83General Maintenance 00.5 Ω Replace fuse OL Testing the FusesTouch top half Input contactsReplacing the Fuses Replacing the BatteryService and Parts Battery and Fuse Replacement Replacement Parts Fluke Part Or Model NumberQuantity Replaceable Parts Fluke Part Number AccessoriesSpecifications KHz 20 kHz2 Models 85 and 87 AC Voltage Function SpecificationsModel 83 AC Voltage Function Specifications Model Resolution Model Model 853 Burden Voltage Typical Current Function SpecificationsΜA B Frequency Counter Specifications Capacitance and Diode Function SpecificationsAccuracy Frequency Counter Sensitivity and Trigger LevelsElectrical Characteristics of the Terminals MIN MAX Recording Specifications

80 Series III specifications

The Fluke 80 Series III digital multimeters are renowned for their robust engineering, precision, and versatility, making them a staple in the toolkit of electricians, engineers, and technicians. Launched by Fluke Corporation, a leading manufacturer of electronic test tools, the 80 Series III has set a benchmark in the multimeter industry for its reliability and performance.

One of the standout features of the Fluke 80 Series III is its wide measurement capabilities. The device can accurately measure AC and DC voltage, DC current, resistance, frequency, and capacitance. This comprehensive feature set allows users to tackle a variety of tasks, from simple household electrical checks to complex industrial applications. The meter's high input impedance prevents loading effects on circuits, ensuring accurate readings, especially in sensitive electronic applications.

Fluke's proprietary True-RMS technology is another defining characteristic of the 80 Series III. This technology ensures that the multimeter provides accurate readings for both non-linear loads and distorted waveforms, which are common in many modern electrical systems. This capability is particularly valuable in diagnosing issues in variable frequency drives, inverters, and other electronic systems that do not present traditional sinusoidal waveforms.

Durability is a key factor in the design of the Fluke 80 Series III. The multimeter is housed in a rugged, impact-resistant case that can withstand the rigors of fieldwork. It features a built-in protective holster with a probe holder, enhancing portability while safeguarding the device against drops and bumps. Furthermore, the 80 Series III boasts an IP67 rating for dust and water resistance, ensuring reliable performance in adverse conditions.

User-friendliness is also a significant aspect of the Fluke 80 Series III. The large, easy-to-read display, combined with intuitive controls, allows users to navigate its functions with ease. The multimeter features a backlight, enabling use in dimly lit environments, while the hold function ensures that readings can be captured and displayed even after disconnecting the probes.

In addition to these features, the Fluke 80 Series III offers various models to cater to specific needs, such as the 87V for highly accurate measurements in industrial environments and the 86V for temperature measurements with added thermocouple support. Each model maintains the high standards of quality and performance that Fluke is known for.

In summary, the Fluke 80 Series III digital multimeters combine advanced features, high accuracy, and rugged durability, making them indispensable tools for professionals who require reliable performance in challenging environments. Whether for routine maintenance or complex troubleshooting, the 80 Series III offers everything necessary to meet the demands of today’s electrical tasks.
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