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MI 3123 SMARTEC Earth Clamp

The MI 3123 SMARTEC Earth Clamp Tester for earth resistance measurements designed to perform 2-wire & 3-wire earth spike testing & 4-wire soil resistivity testing.

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605.64 incl. VAT)
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  • Competitive quote
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Metrel MI 3123 SMARTEC Earth Clamp

The MI 3123 SMARTEC Earth Clamp is an Earth Resistance Tester with the ability to perform 4-wire earth resistance measurement and 4-wire specific earth resistance measurements.

With the optional A 1018 and A 1019 current clamps the instrument can perform 4-wire earth resistance measurement with one current clamp, contactless earth resistance testing with two clamps and TRMS current measurement up to 20 A.

Configurable limits enable a PASS / FAIL evaluation of test results. All the results can be saved on the instrument and then downloaded via the optional software for evaluation and professional report generation after testing.

The lightweight design, large bright LCD screen, built-in help screens, optional downloading via RS232 or USB ports and overvoltage category CAT IV make the MI 3123 an incredible earth resistance measuring instrument.

Metrel MI 3123 Key Features:

Measuring functions:

  • Earth resistance, 4-wire method
  • Earth resistance, 4-wire method with one current clamp (option)
  • Earth resistance, two clamps method (option)
  • Specific earth resistance
  • TRMS current (option)


  • Earth resistance measurement: instrument performs standard 4-wire earth resistance tests with two earthing rods and specific earth resistance measurement
  • Selective earth resistance test: optional 4-wire earth resistance measurement in combination with an additional current clamp is used for measuring earth resistance of individual earthing rods
  • Contactless earth resistance test: earth resistance measurement with 2 current clamps without breaking the loop is intended for measuring resistance of individual earthing rods and is recommended first of all for urban areas
  • Downloadable: downloads via RS232 or USB cable directly to the PC with the help of the optional software
  • Upgradeable: if changes occur to the regulations upgrades can be made to the firmware to keep the instrument up to date
  • Help screens: instrument comes complete with built-in help screens for referencing on site
  • Built-in charger and rechargeable batteries: instrument has a built-in charging circuit and comes complete with a set of rechargeable NiMH batteries
  • Custom limits: the limits can be set on any function, in that case large green and red lights of the LEDs will indicate a PASS or FAIL evaluation of test result
  • Easy to use: large bright LCD display and large buttons enable easy handling of the instrument (even while wearing gloves)
  • Magnetic holder: magnet for fixing instrument on metal surfaces enables hands-free operation

Perfect For:

  • Preventative maintenance
  • Voltage measurements
  • Current measurements
  • Testing earthing resistance
  • Testing main earthing of objects
  • Testing resistance of individual earthing rods in large systems
  • Testing lightning systems
  • Determination of soil resistivity
  • Designing of earthing systems
  • Testing on CAT IV installations (outside installations, main distribution boards, industrial plants)

What comes with the Metrel MI 3123 SMARTEC?

  • MI 3123 Smaretc Earth / Clamp
  • Soft hand strap
  • Test lead 20 m (green)
  • Test lead 4.5 m (blue)
  • Test lead 4.5 m (red)
  • Test lead 20 m (black)
  • A 1022 Earth test rod (4 pcs)
  • A 1147 Rechargeable NiMH AA batteries (6 pcs)
  • 12 V battery charging adapter
  • UK mains cable for charging adapter
  • Short instruction manual
  • Instruction manual on CD
  • Calibration certificate


Comparison Chart for: Metrel MI 3123 SMARTEC Earth Clamp

MI 3121MI 3122MI 3123MI 3110MI 2088
Insulation / ContinuityZ Line-Loop / RCDEarth / ClampEurotestIMEarth Insulation
Insulation resistance
Test voltage (VDC)50 … 100050 … 1000
Insulation resistance measuring rangeup to 30 GΩ
Continuity and low resistance Measurement
Continuity of PE conductor with automatic polarity change, test current 200mA
Low resistance measurement (continuous measurement), test current 7 mA.
Line/Loop Impedance
Line impedance with Ipsc calculation
Loop impedance with Ipsc calculation
RCD Trip Lock loop impedance
Built-in fuse tables for PASS / FAIL evaluation
RCD Testing
Contact voltage without RCD tripping
RCD trip-out time
RCD trip-out current with rising test current
Automatic testing of RCDs
RCD type (general and selective)AC / A
Voltage Frequency
AC voltage measurement
Online voltage monitor
Frequency measurement
Phase Sequence
L1 - L2 - L3
Earth, Current Measurements
Earth resistance 3-(4-)wire method
Earth resistance 3-(4-)wire method with additional current clampOptionOption
Earth resistance measurement with 2 current clampsOptionOption
Specific earth resistanceYes (without ro adapter)
TRMS currentOption
TRMS leakage / load currentOption
IT Earthing System Specific Measurements
Insulation Monitoring Devices (IMD) testing (IT systems)
First fault leakage current (ISFL) measurement (IT systems)
Predefined mini Autosequences
Other Features
Varistor test
Nominal frequency range15 Hz ... 500 Hz15 Hz ... 500 Hz40 Hz ... 500 Hz14 Hz ... 500 Hz45 Hz ... 55 Hz
PASS / FAIL evaluation of test results
Touch electrode
Help menu
Communication Ports
Memory and SoftwareOption
Number of memory levels / memory locations2 / 15003 / 15003 / 15003 / 5002 / 1000
Professional PC SWOptionOptionOption
Advanced PC SWOptionOptionOptionOption
General Data
Safety categoryCAT III / 600 V CAT IV / 300 VCAT III / 600 V CAT IV / 300 VCAT IV / 50 VCAT III / 600 V CAT IV / 300 VCAT III / 300 V CAT II / 600 V
Batteries6 x AA6 x AA6 x AA6 x AA4 x CC
Built-in battery charger


Accessory Code Description Price (Ex VAT)
A1003 Mains Plug £51.72 ADD
A1013 Crocodile Clip Black £7.95 ADD
A1015 Test Probe Blue £6.89 ADD
A1016 Test Probe Red £6.89 ADD
A1018 High Accuracy Current Clamp £296.94 ADD
A1019 Current Clamp £301.86 ADD
A1055 Test Leads (Red; Black) £40.50 ADD
A1062 Test Probe Green £6.89 ADD
A1064 Crocodile Clip Red £7.95 ADD
A1153 20 m Test Lead Black £49.82 ADD
A1154 4 m Test Lead Black £26.50 ADD
A1160 6 Cell AA battery charger £146.28 ADD
A1164 50 m Test Lead Black £79.50 ADD
A1169 Fast charger for 12AA/ 6 C Type £305.28 ADD
A1191 Fuse Locator £224.82 ADD
A1297 Crocodile Clip Brown £7.95 ADD
A1298 Test Probe Brown £6.89 ADD
A1296 Test Leads (Brown; Green; Blue) £46.64 ADD
CS2099 Eurocheck Field Calibrator £307.40 ADD