Fluke 787 user manual Replacing a Fuse

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ProcessMeter

Maintenance

Replacing a Fuse

!Warning

To avoid personal injury or damage to the meter, use only the specified replacement fuse, 440 mA 1000V fast-blow, Fluke PN 943121.

Both current input jacks are fused with a separate 440 mA fuse. To determine if a fuse is blown:

1.Turn the rotary switch to mA A L.

2.Plug the black test lead into COM, and the red test lead into cA.

3.Using an ohmmeter, check the resistance between the meter test leads. If the resistance is about 1Ω, the fuse is good. An open means the fuse is blown.

4.Move red test lead to dmA.

5.Using an ohmmeter, check the resistance between the meter test leads. If the resistance is about 14Ω, the fuse is good. An open means the fuse is blown.

If a fuse is blown, replace it as follows. Refer to Figure 11 as necessary:

1.Remove the test leads from the meter and turn the rotary switch to OFF.

2.Remove the battery door.

3.Remove the three Phillips-head screws from the case bottom and turn the case over.

4.Gently lift the bottom of the front of the case (nearest the input/output jacks) until the top unsnaps from the rear half of the case.

5.Replace the blown fuse with the exact type specified: 440 mA 1000V fast-blow fuse, Fluke PN 943121. Both fuses are the same type.

6.Make sure the rotary switch is in the OFF position.

7.Fit the top of case together, engaging the two snaps (item A). Make sure that the gasket is properly seated.

8.Close the case and reinstall the three screws.

9.Replace the battery door.

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Contents 787 Limited Warranty & Limitation of Liability Table of Contents Index 787Contacting Fluke Read Safety Information before you use the meterIntroduction 787 Safety InformationProcessMeter Symbol Meaning International Symbols MeaningFluke 787 ProcessMeter How to Get StartedInput/Output Jacks Getting Acquainted with the MeterSimulate Transmitter Function Input/Output Jacks Measurement FunctionsSource Current Function Rotary Switch Positions for Measurements Pushbutton Actions FunctionsRotary Switch Positions for mA Output Default Function Pushbuttons Functions PushbuttonsCoarse PushbuttonElements of the Display Display Meaning ElementDisplay Element MA, DC, mV, AC Or kΩ, kHz Auto 400100030 Ranges Measuring a Composite SignalMeasuring Electrical Parameters Input ImpedanceDisplaying Minimum, Maximum, and Average Testing DiodesCompensating for Test Lead Resistance Using TouchHoldSource Mode Using the Current Output FunctionsSourcing Current Changing the Current Span Simulate ModeSimulating a Transmitter Producing a Steady mA Output MA Output Adjust PushbuttonsAdjustment MA Stepping Pushbuttons Manually Stepping the mA OutputAuto Ramping the mA Output MA Step Values Value for each span setting To 20 mAAction Taken Power-Up OptionsPower-Up Options Pushbutton DefaultGeneral Maintenance Battery LifeUsing the Holster and Flex-Stand MaintenanceUsing the Holster and Flex-Stand Replacing the Battery Replacing the BatteryReplacing a Fuse Replacing a Fuse If the Meter does not WorkReplacement Parts and Accessories Quantity Replacement PartsDescription Fluke PN or Model noMP8 Range V dc SpecificationsResolution DC Volts MeasurementAC Volts Measurement Range mV dc Resolution 400.0 Accuracy % of Reading + CountsDC Millivolts Measurement DC Current Measurement AC Current MeasurementMeasurement Current Range ResolutionOhms Measurement Input Range Minimum Sensitivity rms Sinewave 5 Hz to 5 kHz Frequency Counter AccuracyFrequency Counter Sensitivity Diode Test and Continuity Test General SpecificationsSource mode Simulate ModeCertifications CSA, UL, TÜV Index Knob positions, 9 Pushbuttons Loop supply, external Index 787