Fluke 189 user manual Measuring AC Current, Following are some tips for measuring current

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Model 187 & 189

Users Manual

The following are some tips for measuring current:

•If the display shows LEAd5 and you are sure the meter is set up correctly, test the meter’s fuses as described under "Testing the Fuses" in Chapter 6.

•A current meter drops a small voltage across itself, which might affect circuit operation. You can calculate this burden voltage using the values listed in Chapter 7 under Burden Voltage (A, mA, µA).

Measuring AC Current

To measure ac current, set up the meter as shown in Figure 3-11.

The blue pushbutton cannot be used with ac current measurement. All other pushbutton features can be used.

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Contents Model 187 Lifetime Limited Warranty Table of Contents Model 187 Making MeasurementsIii Maintenance SpecificationsList of Tables Model 187 List of Figures Viii Safety Information Before You StartContacting Fluke Safety Information WWarningBefore You Start Symbols International Electrical SymbolsGetting Acquainted IntroductionTurning 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 FunctionSelecting the Range Understanding the DisplayPrimary 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 Measuring Temperature Shock, do not connect the thermocouples to Electrically 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 MemoryStoring Saved Readings Starting LoggingStopping 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 OptionsMaintenance Introduction General MaintenanceTesting the Fuses Replace F2 if Replace F1 if Displayed Replacing the Batteries Battery and Fuse Replacement Replacing the Fuses User-Replaceable PartsCase 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