Fluke 189 user manual Testing Diodes, Capacitance Measurement

Page 49

Making Measurements

Testing Diodes 3

 

189 LOGGING MULTIMETER

AutoHOLD

FAST MN MX

LOGGING

YES

HOLD

MIN MAX

REL

 

 

CANCEL

 

SAVE

NO

 

Hz % ms

RANGE

 

SETUP

nS

 

 

 

 

 

 

 

ac+dc mV

 

 

F

 

C

ac+dc V

 

 

 

A

 

 

 

mA

dB mV

 

 

 

A

dB V

 

 

 

A

 

 

 

mA

 

 

 

 

ac+dc

OFF

 

 

 

A

 

 

 

 

ac+dc

 

 

 

VIEW

 

 

 

CLEAR MEM

 

 

 

 

TEMPERATURE

A

mA

 

COM

V

A

 

 

 

 

 

10A MAX

400mA

CAT

FUSED

 

 

FUSED

1000V

 

 

 

 

+

 

 

 

 

+

 

 

 

 

+

 

 

 

 

+

 

 

 

 

+

 

 

 

 

+

 

 

 

 

+

 

 

 

 

+

 

 

 

 

+

 

 

 

 

ach005f.eps

Figure 3-8. Capacitance Measurement

Testing Diodes

Caution

To avoid possible damage to the meter or to the equipment under test, disconnect circuit power and discharge all high-voltage capacitors before testing diodes.

Use the diode test to check diodes, transistors, silicon controlled rectifiers (SCRs), and other semiconductor devices. The test sends a current through a semiconductor junction, then measures the junction’s voltage drop. A typical junction drops 0.5 V to 0.8 V. In diode test, the beeper is active. It beeps briefly for a normal junction and is on continuously if a short is detected.

To test a diode out of a circuit, set up the meter as shown in Figure 3-9.

In a circuit, a similar diode should still indicate a forward- bias reading of 0.5 V to 0.8 V; however, the reverse-bias reading can vary depending on the resistance of other pathways between the probe tips.

The blue key toggles between diode test and capacitance. Since diode test uses a fixed range, R cannot be used.

3-13

Image 49 Fluke 189 user manual Testing Diodes, Capacitance Measurement
Contents Model 187 Lifetime Limited Warranty Table of Contents Making Measurements Model 187Iii Specifications MaintenanceList of Tables Model 187 List of Figures Viii Before You Start Safety InformationContacting Fluke WWarning Safety InformationBefore You Start International Electrical Symbols SymbolsIntroduction Getting AcquaintedTurning the Meter On Automatic Power Off Battery ConsiderationsAutomatic Backlight Off Low Battery IndicationRotary Switch Rotary SwitchPushbuttons PushbuttonsBlue Key Function Rotary Switch Selections Position Rotary Switch FunctionView MEM Rotary Switch PositionsButton Pushbuttons Yellow Button Description Function Yellow Button Function Pushbuttons Button DescriptionUnderstanding the Display Selecting the RangePrimary Display Secondary Display Bar GraphDisplay Features Number Feature Display Features Description 8.8.8 Display Features NumberDisplay Features Description Number FeatureFMS8888 HM8888 8.8 Display Features Number 51000Input Terminals Using the Input TerminalsDisplay Hold and AutoHOLD Using Display HoldUsing MIN MAX Using AutoHOLDModel 187 Min Max Avg Using Fast MN MXUsing Hold with MIN MAX or Fast MN MX Using Relative Mode RELMeasuring Voltage Making MeasurementsAC Voltage Measurement Measuring AC VoltageDBm Display DB Measurements in AC Volts FunctionsBoth AC and DC Voltage Measurements Measuring DC VoltageAC and DC Display AC over DC DC over ACCapacitors before measuring resistance Measuring ResistanceOFF Automatically subtract this value Testing for ContinuityUsing Conductance for High Resistance Tests For in-circuit tests, turn circuit power off Conductance Measurement Measuring Capacitance Capacitance Measurement Testing DiodesDiode Test Shock, do not connect the thermocouples to Measuring TemperatureElectrically live circuits Input Ranges Measuring CurrentMeasuring Current Input Alert FeatureFollowing are some tips for measuring current Measuring AC Current11. AC Current Measurement Measuring DC Current Current through one component Total current to circuit13. Functions Allowing Frequency Measurement Measuring Frequency14. Hz Display Measuring Duty CycleMeasures Negative Pulse Measures Positive Pulse16. Duty Cycle Display Measuring Pulse WidthStart and Stop on Negative Slope Start and Stop on Positive Slope18. Pulse Width Display Model 187 Types of Memory Using Memory & Communications FeaturesSaved Readings Memory Logged Readings MemoryStarting Logging Storing Saved ReadingsStopping Logging To avoid electric shock, disconnect the test Viewing Memory DataMEM View DisplayClearing Memory Using Communications 187Model 187 Selecting Setup Options Changing the Default SettingsFactory Default Function Specific Setup SelectionsPrecondition OptionChoices Common Setup SelectionsAdjusting the Temperature Offset Changing the Default Settings Setting the Power Off Timeout Selecting Display Resolution 3 1/2 or 4 1/2 DigitsSetting the Line Main Frequency Setting the 24-Hour ClockSaving Setup Options Returning to Factory DefaultsIntroduction 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 Safety and Compliances SpecificationsPhysical Specifications Feature Summary Basic Specifications Detailed Accuracy Specifications 45-1 kHz Accuracy Function20 kHz KHz-100 kHzDC a 500.00 Ω Capacitance Diode Test MIN MAX AVG Burden Voltage A, mA, µA Frequency Counter SensitivityInput Characteristics