MEWOI4000-Earth Ground Resistance Tester-upgraded version

  • Características:
    1.2/3-wires measurement of earth resistance, voltage to ground measurement, low value resistance measurement 2.Capable of measuring earth resistance and voltage 3.Range:0.01Ω~2000Ω; 0~600V, 4.Accuracy:0.01Ω,1V 5.Data upload: RS232 interface 6.Date storage:400 sets
  • Modelo:
  • Nombre:
    MEWOI4000-Earth Ground Resistance Tester
Electricity Testing Instruments manufacturer, Support OEM/ODM, your testing specialist


MEWOI4000 Digital Earth Resistance Tester is specially designed and manufactured for field measurement, adopting the latest digital and micro-processing technology, 3-pole or 2-pole method for earth resistance measurement, with a unique function of wire resistance verification, anti-interference capability and the ability to adapt to the environment, to ensure high precision, high stability and reliability for prolonged measure, which is widely used in electric power, telecommunications, meteorology, oil field, construction, lightning protection, industrial electrical equipment and other earth ground resistance measurement.


MEWOI4000 Digital Earth Resistance Tester has a unique function of wire resistance verification,more accurate on measuring on-site low value earth ground resistance, which can avoid error caused by resistance change due to prolonged usage of testing wire; avoid error caused by testing wire that is failed to be fully inserted into tester interface or by poor contact; avoid error caused by users’ replacing or lengthening testing wires.


MEWOI4000 Digital Earth Resistance Tester is composed of host machine, monitoring software, testing wires, communication wires and others. The large LCD display of host machine is with blue backlight and bar graph indicating that can be seen clearly. At the same time it can store 400 sets of data, fulfilling historical inquiry and online real-time monitoring through monitoring software, dynamic display, with the maximum, minimum, and mean indicators, with alarm settings and alarm indicator, and with the functions like historical data access, reading, preservation, report forms, printing and so on.

Measuring Range and Accuracy

Measuring Functions

Measuring Range



Earth Ground Resistance



 (Auxiliary earth ground resistance 100Ω±5%,voltage to ground<10V)





Earth Ground Voltage

0~600V AC



(Remark: 23℃±5℃,below 75%rh)

 Selection Guide

clamp sizeRS232Data StorgeAudible and visible alarm Other
0.01Ω-200Ω    0.01Ω65mm×32mmoptional 
MEWOI3000+MEWOI3000B+_副本.jpg0.01Ω-1200Ω   0.01Ω65mm×32mmoptional 99sets



0.01Ω,0.05mA  65mm×32mmoptional 99sets
MEWOI3800CMEWOI3800C_副本80.jpg0.01Ω-200Ω    0.01Ω60mm*30mmAppoint with RS485 communication interface, provide standard MODBUS-RTU communication protocol×

MEWOI3800DMEWOI3800D_副本80.jpg0.01Ω-200Ω  0.01Ω60mm*30mm×
LCD display,warning function.



2/3-wires measurement of earth resistance/voltage

earth resistance:0.01Ω~30.00KΩ;

soil resistivity:0.01Ωm~9000KΩm;


2/3/4-wires measurement of earth resistance,soil resistivity,and earth voltage

earth resistance:0.01Ω~30.00KΩ;AC Leakage current: 0.00mA~600A; 

soil resistivity:0.01Ωm~9000KΩm;Earth Voltage:0.0~100.0V,dual clamp: 0.01Ω-100Ω

2/3/4-wires,selection & dual clamp method to measure the earth resistance,soil resistivity,earth voltage,AC voltage,AC leakage current,warning function.


Earth ground resistance measurement, voltage to ground measurement, low value resistance measurement

Power Supply

DC 9V(Zi-Mn dry battery R14S 1.5V 6 PCS, continuous standby for 300 hours )


Controllable blue backlight, suitable for use in dark place. 

Measuring Mode

Precise 3-pole measurement, simple 2-pole measurement

Measuring Method

Earth ground resistance: rated current change-pole method, measurement current 3mA Max,820Hz;

Voltage to ground: average value rectification

Data Mode

Average value, maximum, minimum

Wire Resistance Verification

Avoid error caused by testing wire that is failed to be fully inserted into tester interface or by poor contact or by users’ replacing or lengthening testing wires, making it more accurate for earth ground resistance measurement.

Display Mode

4-digital super-large LCD display, blue screen backlight

Measuring indicator

During measurement, LED flash indicator, LCD count down display

LCD Dimension

128mm×75mm;Display field:124mm×67mm


L×W×H: 215mm×190mm×95mm

Testing Wires

Three wires: each for Red 20m, Yellow 10m, and Green 5m

Simple Testing Wire

2 wires: each for Red 1.6m and Green 1.6m

Auxiliary grounding rod

2 PCS:Φ10mm×150mm

Measuring Rate

Voltage to ground: about 3 times/second; earth ground resistance: about 5 seconds/time

Measuring Times

Over 5000 times

(Measuring 10Ω for one time on 20Ω range and take a pause for 25s)

Circuit Voltage

Measuring voltage to ground: measuring below AC 600V

RS232 Interface

Possess RS232 interface, software supervision, storage data can be uploaded to computer, saved or printed.

Communication Wire

One piece of RS232 communication wire, with length 1.5m

Data Storage

400 sets, flash display “FULL” icon to indicate storage is full

Data Hold

Data hold function: “HOLD” icon display

Data Read

Data read function: “READ” icon display

Overflow Display

Exceeding measuring range overflow function: “OL” icon display

Alarm Function

When measuring value exceeds alarm setting value, there is “Toot-toot-toot” alarm hint

Battery Voltage

When battery voltage decreases to about 7.8V, battery voltage low icon will display, reminding to replace battery.  

Power Consumption

Backlight:25mA Max

Standby: 25mA Max(Backlight shut off)

Measurement:70mA Max(Backlight shut off)


Tester:1443g(including battery)

WorkingTemperature & Humidity

-10℃~40℃;below 80%rh

Storage temperature & humidity

-20℃~60℃;below 70%rh

Overload Protection

Measuring earth ground resistance: between each interfaces of E-P,E-C, AC 280V/3 seconds

Insulation Resistance

Over 10MΩ(between circuit and enclosure it is 500V)

Withstanding Voltage

AC 3700V/rms (Between circuit and enclosure)

Electromagnetic Features

Wireless frequency electromagnetic field

Protection Type

IEC61010-1,IEC1010-2-31,IEC61557-1,5,IEC60529(IP54),Pollution etc. 2,CAT Ⅲ 300V


Tester:1 pc; Ground rod:2 pcs; Testing wire: 3 pcs ;Simple testing wire: 2 pcs; RS232 line:1 pc; Software disk: 1 pc; Tester bag:1 pc

Tester:1 pc; Ground rod:2 pcs; Testing wire: 3 pcs ;Simple testing wire: 2 pcs; RS232 line:1 pc; Software disk: 1 pc; Tester bag:1 pc