Fluke 1625 user manual US1

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1625

Users Manual

The Influence of Potential Gradient Areas on Earth Resis- tance Measurement

To pick off the true voltage drop from the earthing resistance (= the resistance between the earth electrode and the soil potential FE) it is to be assured that the probe is set outside the potential gradient area of all connected earth electrodes and the auxiliary earth electrode H.

 

 

 

 

UG

 

 

 

 

 

 

I

 

 

 

 

 

 

G

 

 

 

US1

 

US2

US2

US4

I

 

 

V

I1

V

I2

V

V

 

 

 

 

 

H

E1

S1

S2

S3

S4

E2

 

 

US1

 

US2

US3

 

US4

 

 

 

 

 

 

 

 

 

 

 

 

 

 

FE

UG

 

 

 

 

 

 

 

edw059.eps

A probe positioned inside a potential gradient area leads to incorrect measuring results. As it can be seen in the picture above, probe voltages US1 and US2 of probes S1 and S2 deliver a value too low, which also means that the earthing resistance appears to be lower than it actually is(low resistance). Probe S 4 with US4 on the other hand, picks up a value too high which indicates a worse (high resistance) earthing conditions.

Only probe S3 picks up the correct voltage between earth electrode and soil potential FE.

For that reason it is advisable to repeat each measurement with repositioned probes and only to regard a measurement as successful and accurate if several subsequent measurements result in the same values.

Normally, a distance of 20 m to the earth electrode and to the probes to each other is sufficient.

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Contents 1625 Limited Warranty and Limitation of Liability Table of Contents 1625 List of Tables 1625 List of Figures 1625 Earth/Ground Tester IntroductionDisplays the Fluke 1625 Earth/Ground Tester Models and Accessories Lists the models and accessoriesSafety Instructions Setup Qualified StaffUnpacking Checking the Scope of DeliveryAdditional Accessories GeneralAssembly Description of FunctionsMeasurement of Interference Voltage UST Measurement of Interference Frequency FSTMeasurement of Earthing Resistance RE Selective Measurement of Earthing Resistance RE aResistance Measurement R~ Low Resistance Measurement RFSpecifications LO-BATSpecifications 1625 Measurement of Interference Frequency F ST Measurement of Interference Voltage DC + AC USTEarthing Resistance R E Ence Quan Fied Operating Code Relevant 100% RH with Umeas = 48 RH with Umeas = 20 Resolution Selective Measurement of the Earthing Resistance REA RH RS + 2000Ω ⋅1.25 ⋅10−6 % + 5digits+2 digit KΩ .. .99 kΩ 10 Ω 30.0 kΩ .. .9 kΩ 100 Ω Resistance Measurement RF Compensation of Lead Resistance RK Description of the Operating Elements Illustrates the operating elements described belowDo not open or close the instrument with force Description of Display Elements Display ElementsProcedure of Measurements EfghPower on Functions Standard modeOperation Activation of display illuminationControl Loop Control Loop See Compensation of Earth Electrode Connecting Lead Checking of Correct Measuring Connection Socket Alloca- tion Safety Control Measurements Measurement of Interference Voltages and Frequen- ciesMeasurement of Earthing Resistances Measurement of Interference Voltages and FrequenciesPole/4-pole Measurement of Earthing Resistance Earthing Resistances Measurement MethodRemarks for the setting of earth spikes Evaluation of measured value RE1 20 m Remarks for the Setting of Earth Spikes Measurements on High Voltage Pylons Accordingly, these equivalent resistances are displayed as RE = Correcting Clip-on Transformer Errors Measuring Earthing Impedance with 55 Hz RWithclip − ontransformer Compensation of Earth Electrode Connecting Lead Compensation of Earth Electrode Connecting LeadMeasurement of Soil Resistivity Measurement of Soil Resistivity= 2π .a.RE Restivity Soil Distances of Probe Measurement of Resistances Resistance Measurement R~Resistance Measurement RF Resistance Measurement RFCompensation of Measuring Lead Resistance Evaluation of Measured ValueChanging of All Data Settings with Personalized Code Compensation of Measuring Lead ResistanceFunction Parameter Setting range Standard Presetting Storing a Code Deleting a Code Description of Displays Description of Displays Function ConditionFunction Displays Condition Too high 2nd aux ON/OFF No reactions to button control etc Care and Maintenance EE PromCare and Maintenance Replacing BatteriesRecalibration StorageStakeless Earth/Ground Resistance Testing IntroductionComply with DIN ISO Principle of Operation Purpose= R X + Is a reasonable approximation Operation Settings on the Tester Erder 10 cmApplications Lightning Protection Footing ground Description of Displays SignificanceDisplay Significance Earthing Resistance Earthing Resistance Soil Resistivity ρE = 1 mJan July Dec Month Measuring Method Potential Gradient Area US1 Earth Impedance R* on High Voltage Transmission Lines 1625

1625 specifications

The Fluke 1625 is a versatile and essential tool in the realm of insulation testing, primarily aimed at electricians, maintenance professionals, and equipment specialists. Throughout its design, Fluke has incorporated a range of features and technologies intended to enhance testing efficiency, accuracy, and user experience, making the 1625 a standout choice for those in need of reliable insulation measurement tools.

One of the key features of the Fluke 1625 is its ability to perform insulation resistance testing with several voltage settings. The device offers test voltages of 250V, 500V, and 1000V, making it adaptable for different applications, including low-voltage and high-voltage systems. This flexibility is paramount in ensuring that technicians can perform tests on a wide variety of electrical systems without needing multiple devices.

The 1625 also boasts an impressive insulation range of up to 4 GΩ, providing the capability to measure insulation resistance accurately across a spectrum of installations. A notable technology integrated into the unit is the automatic discharge function, which ensures that any stored energy in capacitive components is safely released after testing, enhancing the safety of operations.

Furthermore, the Fluke 1625 includes a patented 'Insulation Diagnostic' feature that assists users in identifying problematic areas in an electrical system. This feature helps professionals determine whether insulation is adequate, helping to prevent potential failures, accidental shorts, and system downtimes.

In addition to insulation resistance testing, the Fluke 1625 also supports other functionalities, including continuity testing and low-resistance measurements. This multi-functional capability streamlines operations, allowing technicians to conduct multiple tests without switching devices, resulting in increased productivity.

The device is designed with user-friendliness in mind, featuring an intuitive interface complete with large buttons and a clear display. This makes it easier for users to navigate through different testing modes and review results. To further enhance usability in challenging environments, the 1625 has a rugged, durable design, ensuring it can withstand the rigors of job sites.

Another significant characteristic of the Fluke 1625 is its ability to log test results for further analysis. It can store up to 99 datasets, which can be later reviewed or downloaded for reporting purposes. This data management capability is crucial for maintaining records, fulfilling compliance requirements, and improving operational efficiencies.

In conclusion, the Fluke 1625 is a robust and comprehensive insulation tester that incorporates essential features and advanced technologies. With its versatility, safety mechanisms, and user-friendly design, it stands out as an indispensable tool for electrical professionals committed to ensuring system reliability and safety.