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Musktool-ETCR2900 Online Earth Resistance Tester,online ground resistance tester
Musktool-ETCR2900 Online Earth Resistance Tester,online ground resistance tester
Musktool-ETCR2900 Online Earth Resistance Tester,online ground resistance tester
Musktool-ETCR2900 Online Earth Resistance Tester,online ground resistance tester

Musktool-ETCR2900 Online Earth Resistance Tester,online ground resistance tester

2023-07-06 14:53:42  

Online Earth resistance Tester

  • Main Feature :
  • Serial No. :

Contact Us For QuotationEmail:  464560351@qq.comWhatsapp&Wechat:+8618620373879


ETCR2900 Contact Type On-line Earth Resistance Tester is high-tech product that our company has devoted to "Earth Resistance Detect Technology Research" for more than ten years, Adopt precision 3-wire or simple 2-wire measurement method to test the earth resistance. Adopt average value rectification method to test grounding voltage, online detection, real-time monitoring. User can select RS232 or RS485 communication, according the protocol MODBUS to secondary development, build the network, realize remote multipoint online monitoring etc.

ETCR2900 Contact Type On-line Earth Resistance Tester displayed by super large LCD, very clear and obvious. The alarm critical value can be set via the button, and with the sound and light alarm indication. Ensure the high accuracy, high stability and high reliability of real-time online monitoring of grounding resistance value in various place.

ETCR2900 Contact Type On-line Earth Resistance Tester suitable for transmission line tower grounding, underground mine equipment grounding , weather lightning protection grounding, petrochemical grounding ,communication base station grounding, power substation grounding , railway grounding , building warehouse grounding , electrical equipment grounding, etc.

ETCR2900 Accessories


  • Detector

  • 9P wiring terminal

  • Warranty card/Qualification card

  • Paper Box


Measurement Range & Accurancy

Measurement Function




Earth Resistance


±2%rdg±3dgt (auxiliary earth resistance 100Ω±5%,Voltage to earth<10V)



±2%rdg±3dgt (auxiliary earth resistance 100Ω±5%,Voltage to earth<10V)



±2%rdg±3dgt (auxiliary earth resistance 100Ω±5%,Voltage to earth<10V)

Earth Voltage

0~600V AC



(Note: 23℃±5℃,below 75%rh)

Technical Parameter




Online monitoring of grounding resistance, grounding voltage, equipotential bonding resistance, and low value resistance

Power Supply

Standard: 12V±1VDC、400mA Max; Optional: 24V±1VDC

Test Method

precision 3-wire or simple 2-wire measurement method

Measurement Method

Ground Resistance :Rated current pole method, measuring current 11mA Max,128Hz;

Ground Voltage:Average rectification

Data Mode

Average value

Display Mode

4 Digits large LCD display

Measurement Indication

In measurement, LCD count down indication

LCD size

128mm×75mm; Display area:124mmX67mm

Tester Dimension


Measurement Time

Voltage to earth: about 2 times/seconds; Grounding resistance: about 30seconds/times

Measurement Times

Above 10,000 times

Line Voltage

Measurement voltage to earth: AC below 600V

Tester Interface

Plug Terminal Block: 9-pin terminal block

Data Communication

RS485 (optional RS232).


Automatic shift

Data Storage

400 sets, flashes display "FULL" symbol indicate that storage full

Interval time

Automatic monitoring interval time of setting range: 1 ~ 999 hours

Data Access

Data access function: display "READ" symbol

Overflow Indication

Over range overflow function: display "OL" symbol

Power Consumption

Standby:25mA Max

Measurement:400mA Max

Alarm Indication

  audible and visual alarm

Power Voltage

When power voltage lower than 10V, display low power voltage symbol, and remind to replace battery

Tester Weight


Working Environment

-10℃~40℃;below 80%rh

Store Environment

-20℃~60℃;below 70%rh

Overload Protection

In measurement of ground resistance:E-P、E-C AC 280V / 3 seconds between each terminal

Insulation Resistance

above 10MΩ  (500V between circuit and outside shell)

Withstand Voltage

AC 3700V/rms (Between the circuit and the shell)

Electromagnetic characteristics

IEC61010-4-3,Wireless frequency electromagnetic field≤1V/m

Suitable Safety Standard

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

Structure & Size


Principle & Application

  • Measurement Principle

1.Earth voltage measurement adopts average value rectification method. 


2.Earth resistance measurement adopts rated current change-pole method.

That is, the AC rated current I (11mA Max,128Hz) flows between the measuring

object E (ground electrode) and the C (current electrode); Get the potential difference

V between the E and the P (voltage electrode), and then get the grounding resistance

value Rx according to the formula: R=V/I.

3.The working error (B) is the error obtained within the rated working conditions, which is calculated from the inherent error (A) and variation error (Ei).


       A: Intrinsic error                                                     E1: Variation due to position change 

E2:Variation due to power supply voltage change       E3:Variation due to temperature change     

E4:Variation due to interference voltage change            E5:Variation due to contact electrode resistance change

E7: Variation due to system frequency change              E8:  Variation due to system voltage change

  • Wiring Connection & Measurement Method


1.First: the user needs to make auxiliary grounding poles P and C every 5 ~ 10 meters on the same straight line near the monitored grounding pole E. Auxiliary grounding pole should adopt grounding materials or stainless steel material, prevent rust and rot, the grounding resistance value as small as possible, the general grounding resistance requirements no more than 100 Ω, ground voltage is less than 10V, so as to ensure the accuracy of the on-line monitoring.

Secondly: according follow table to connect the detector, computer, power supply, etc. It`s better that the connection between the detector and the auxiliary earth pole secured by electric power wire (for later maintenance and disassembly), or by welding.


2.The grounding resistance on-line monitoring usually adopts the precise three-wire method, but also can use the simple two-wire method to test. The simple two-wire method is used to measure the grounding resistance by using the existing grounding electrode which grounding resistance value is smaller as the auxiliary grounding electrode and short-connecting the C and P interfaces. Auxiliary grounding rods C and P can be instead by metal water pipes, fire hydrants and others metal embedded objects, common grounding of commercial power systems or lightning protection grounding poles of buildings, etc. During measuring, pay attention to removing the oxide layer at the connection point of the selected metal auxiliary grounding body. Simple two wires method wiring connection as right side figure:

The simple method measure the grounding resistance, the tester reading is the sum of the grounding resistance of the grounded body to be measured and the grounding resistance of the commercial grounding body.



Which: R --- The tester reading value;

RX ---The grounding resistance value of measured grounding object;

re--- the grounding resistance value of a common grounding body such as a commercial power system.

Then, the earth ground resistance value of measured grounding body is:


Use simple method to measure the grounding resistance, try best to select the grounding body with a smaller re value as the auxiliary grounding electrode, so that the detector reading is closer to the real value.

Related Series Model

ModelRangeLCD SizeDifference


0-600V AC

128mm×75mmCan build the Wired Network System
ETCR2900B 0.01Ω~2000Ω

0-600V AC

47mm×28.5mmCan build the Wired Network System and Wireless Network System

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