Fluke 187 user manual Measuring Resistance, Capacitors before measuring resistance

Page 41

Model 187 & 189

 

 

 

 

 

 

 

Users Manual

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Measuring Resistance

 

 

 

189 LOGGING MULTIMETER

 

Caution

 

 

 

 

 

 

 

 

To avoid possible damage to the meter or to

 

 

 

 

 

 

 

 

the equipment under test, disconnect circuit

 

 

 

 

 

 

 

 

power and discharge all high-voltage

 

AutoHOLD

FAST MN MX

LOGGING

YES

 

capacitors before measuring resistance.

 

HOLD

MIN MAX

REL

 

 

 

 

 

 

CANCEL

 

SAVE

NO

 

Resistance is an opposition to current flow. The unit of

 

 

 

Hz % ms

RANGE

 

 

 

SETUP

nS

 

 

 

 

resistance is the ohm (). The meter measures resistance

 

 

 

 

 

 

 

ac+dc mV

 

 

F

 

 

 

C

 

by sending a small current through the circuit.

 

ac+dc V

 

 

 

mA

 

 

ac+dc V

 

 

 

 

A

 

 

 

dB mV

 

 

 

A

 

 

 

 

V

 

 

 

A

 

The meter’s resistance ranges are 500.00 , 5.0000 k

,

 

 

 

 

ac+dc

 

dB

 

 

 

mA

 

 

 

 

OFF

 

 

 

A

 

50.000 k, 500.00 k, 5.0000 M, 30.000 M, and

 

 

 

 

 

VIEW

 

 

 

 

 

 

 

ac+dc

 

 

 

 

 

 

 

CLEAR MEM

 

500.0 M.

 

 

 

 

 

 

TEMPERATURE

 

 

A

 

mA

 

COM

V

 

 

 

 

A

 

 

 

 

 

 

 

 

 

 

To measure resistance, set up the meter as shown in

 

 

10A MAX

400mA

CAT

 

 

 

FUSED

 

 

 

 

 

 

FUSED

1000V

 

 

 

 

 

 

 

 

 

 

Figure 3-5.

 

 

 

 

 

 

 

 

All pushbutton functions are available with resistance

 

 

 

 

 

 

 

 

measurements. The blue key cycles to continuity and

 

 

 

 

 

 

 

 

conductance measurement, which are described later in

 

 

 

 

 

+

 

this chapter.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Note

 

 

 

 

 

 

 

 

In the Ohms Mode, a negative sign (-) on the

 

 

 

 

 

 

 

ach002f.eps

display indicates the presence of voltage. This

 

 

 

 

 

 

 

will cause reading errors.

 

Figure 3-4. DC Voltage Measurement

 

 

3-6

Image 41
Contents Model 187 Lifetime Limited Warranty Table of Contents Making Measurements Model 187Iii Specifications MaintenanceList of Tables List of Figures Viii Contacting Fluke Safety InformationBefore You Start WWarning Safety InformationBefore You Start International Electrical Symbols SymbolsTurning the Meter On Getting AcquaintedIntroduction 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 DescriptionPrimary Display Selecting the RangeUnderstanding the 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 Voltage DBm 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 Electrically live circuits Measuring TemperatureShock, do not connect the thermocouples to 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 Types of Memory Using Memory & Communications FeaturesSaved Readings Memory Logged Readings MemoryStopping Logging Storing Saved ReadingsStarting Logging To avoid electric shock, disconnect the test Viewing Memory DataMEM View DisplayClearing Memory Using Communications 187Selecting 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 DefaultsTesting the Fuses MaintenanceIntroduction General Maintenance Replace F2 if Replace F1 if Displayed Replacing the Batteries Battery and Fuse Replacement Case of Difficulty Replacing the FusesUser-Replaceable Parts 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