Fluke 189 user manual Measuring Frequency, Functions Allowing Frequency Measurement

Page 58

Model 187 & 189

Users Manual

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.

Figure 3-13 highlights the function selections that allow frequency measurement.

To measure frequency, select an appropriate function, connect the meter signal source, and press N.

The meter autoranges to one of four frequency ranges:

500.00Hz, 5.0000 kHz, 50.000 kHz, and 999.99 kHz. Figure 3-14 shows a typical frequency display.

		nS
	mV	F
	ac+dc	C
	V	A
	V	mA
	ac+dc	mA
	mV	A
	dB
	V	A
	V	mA
	dB	ac+dc
	OFF	A
		ac+dc
		VIEW MEM
		CLEAR MEM

tc021f.eps

Figure 3-13. Functions Allowing Frequency

Measurement

3-22

Image 58

Contents Model 187 Lifetime Limited Warranty Table of Contents Model 187 Making MeasurementsIii Maintenance SpecificationsList of Tables Model 187 List of Figures Viii Before You Start Safety InformationContacting Fluke Safety Information WWarningBefore You Start Symbols International Electrical SymbolsIntroduction Getting AcquaintedTurning the Meter On Battery Considerations Automatic Power OffLow Battery Indication Automatic Backlight OffRotary Switch Rotary SwitchPushbuttons PushbuttonsRotary Switch Selections Position Rotary Switch Function Blue Key FunctionRotary Switch Positions View MEMButton Pushbuttons Yellow Button Description Function Pushbuttons Button Description Yellow Button FunctionUnderstanding the Display Selecting the RangePrimary Display Bar Graph Secondary DisplayDisplay Features Number Feature Display Features Description Display Features Number 8.8.8Number Feature Display Features DescriptionDisplay Features Number 51000 FMS8888 HM8888 8.8Using the Input Terminals Input TerminalsUsing Display Hold Display Hold and AutoHOLDUsing AutoHOLD Using MIN MAXModel 187 Using Fast MN MX Min Max AvgUsing Relative Mode REL Using Hold with MIN MAX or Fast MN MXMaking Measurements Measuring VoltageMeasuring AC Voltage AC Voltage MeasurementDB Measurements in AC Volts Functions DBm DisplayMeasuring DC Voltage Both AC and DC Voltage MeasurementsAC over DC DC over AC AC and DC DisplayMeasuring Resistance Capacitors before measuring resistanceOFF Testing for Continuity Automatically subtract this valueUsing Conductance for High Resistance Tests For in-circuit tests, turn circuit power off Conductance Measurement Measuring Capacitance Testing Diodes Capacitance MeasurementDiode Test Shock, do not connect the thermocouples to Measuring TemperatureElectrically live circuits Measuring Current Input RangesInput Alert Feature Measuring CurrentMeasuring AC Current Following are some tips for measuring current11. AC Current Measurement Measuring DC Current Total current to circuit Current through one componentMeasuring Frequency 13. Functions Allowing Frequency MeasurementMeasuring Duty Cycle 14. Hz DisplayMeasures Positive Pulse Measures Negative PulseMeasuring Pulse Width 16. Duty Cycle DisplayStart and Stop on Positive Slope Start and Stop on Negative Slope18. Pulse Width Display Model 187 Saved Readings Memory Using Memory & Communications FeaturesTypes of Memory Logged Readings MemoryStarting Logging Storing Saved ReadingsStopping Logging Viewing Memory Data To avoid electric shock, disconnect the testView Display MEMUsing Communications 187 Clearing MemoryModel 187 Changing the Default Settings Selecting Setup OptionsPrecondition Function Specific Setup SelectionsFactory Default OptionCommon Setup Selections ChoicesAdjusting the Temperature Offset Changing the Default Settings Selecting Display Resolution 3 1/2 or 4 1/2 Digits Setting the Power Off TimeoutSetting the 24-Hour Clock Setting the Line Main FrequencyReturning to Factory Defaults Saving Setup OptionsIntroduction General Maintenance MaintenanceTesting the Fuses Replace F2 if Replace F1 if Displayed Replacing the Batteries Battery and Fuse Replacement User-Replaceable Parts Replacing the FusesCase of Difficulty MP8 MP9 Specifications Safety and CompliancesPhysical Specifications Feature Summary Basic Specifications Detailed Accuracy Specifications 20 kHz Accuracy Function45-1 kHz KHz-100 kHzDC a 500.00 Ω Capacitance Diode Test MIN MAX AVG Frequency Counter Sensitivity Burden Voltage A, mA, µAInput Characteristics