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Metrel MI 3123 SMARTEC Earth Clamp

The Metrel MI 3123 SMARTEC Earth / Clamp is a new generation earth resistance tester with the ability to perform 4-wire earth resistance measurement and 4-wire specific earth resistance measurement

Important Calibration Information

This instrument comes with a manufacturers calibration certificate.
Please see 'Calibration Options' in the description for more details.

Next Day Delivery (subject to availability)

£425.00 excluding VAT £510.00 including VAT @ 20% Regular Price: £732.00
  • Downloadable RS232/USB
  • Earth resistance, 4-wire method
  • Earth resistance, two clamps method
  • Measure Earth Resistance
  • Specific earth resistance
  • TRMS current (option)
  • Earth Spikes Included
  • Backlit Display
  • FreeDelivery
  • 30DayMoneyBack
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  • Description
  • Features & Specification
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Metrel MI 3123 SMARTEC Earth Clamp

An incredible earth resistance measuring instrument

The MI 3123 SMARTEC Earth / Clamp is a new generation earth resistance tester with the ability to perform 4-wire earth resistance measurement and 4-wire specific earth resistance measurement. 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.

*Important Calibration Information:

This instrument comes complete with the manufacturer's calibration certificate. Please be aware that these certificates are generic and may also be time lapsed.
If you would prefer a personalised full traceable calibration certificate applied to the equipment before dispatch, then please select this option from the drop-down menu above, an additional calibration charge will apply.

Metrel MI 2123 (Standard Set) Comes Supplied With:

  • MI 3123    Smaretc Earth / Clamp
  • 20901090 Soft hand strap
  • 20691900 Test lead 20 m (green)
  • 20691012 Test lead 4.5 m (blue)
  • 20691015 Test lead 4.5 m (red)
  • 20691901 Test lead 20 m (black)
  • A 1022 Earth test rod (4 pcs)
  • A 1147 Rechargeable NiMH AA batteries (6 pcs)
  • 83005447 12 V battery charging adapter.
  • 83005401 UK mains cable for charging adapter
  • Short instruction manual
  • Instruction manual on CD
  • Calibration certificate


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).

Key Features:

  • 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 & 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.

Typical Applications:

Electrical Power Systems

  • Power Plants
  • Photovoltaic
  • Distribution
  • Safety
  • Earthings / Funnels

Industrial Systems

  • LV Installations Safety / Quality

Special Installations / Locations:

  • Construction Sites
  • Railway Systems
  • Ships / Boats / Marina Places
  • Military / Police Vehicles
  • Mobile LV Generator Units
  • Mobile Video / Audio / Concert Halls / Fair Playground

About Metrel

Metrel was established in 1957 as a factory for the production of electrical measuring instruments and components for the domestic market and grew from there to become one of world’s leading manufacturers of measuring and testing equipment. They are one of the few companies in the industry that develops and manufactures products at a single location, starting with design and ending with final assembly, quality control and calibration.

Earth Resistance    
Earth resistance 4-wire method and earth resistance one clamp method
Measuring range according to EN61557 is 0.67Ω ÷ 9999Ω
Measuring Range  Resolution   Accuracy 
0 ÷ 19.99Ω 0.01Ω  ±(3% of reading + 3 digits) 
20 ÷ 199.9Ω 0.1Ω ±(3% of reading + 3 digits)
200 ÷ 1999Ω ±5% of reading
2000 ÷ 9999Ω ±10% of reading
Automatic Test of Probe Resistance Yes  
Automatic Test of Voltage Noise Yes  
Open-Terminal Test Voltage 40VAC  
Test Voltage Frequency 125Hz  
Short-Circuit Test Current <20mA  
Low Clamp Current Indication Yes  
Noise Current Indication Yes  
Earth Resistance (Two Clamps Method)    
Measurement Range Resolution Accuracy
0 ÷ 19..99Ω 0.01Ω  ± (10% of reading + 10 digits) 
20 ÷ 30.99Ω 0.1Ω ± (20% of reading)
30.1 ÷ 39.99Ω 0.1Ω ± (30% of reading)
Test Voltage Frequency 125Hz  
Noise Current Indication Yes  
Low Clamp Current Indication Yes

Standard FREE 3-5 Day Courier Delivery – UK Mainland only - Zones A & B
Included in the price for all orders over £40.00 (exc vat). Sent using express courier, delivered within 3-5 working days from the date of your order, subject to availability.

Standard 1-2 Day Express Courier Delivery – UK Mainland only - Zones A & B
£4.50 for all all orders under £40.00 (exc vat). Sent by express courier, delivered within 1-2 working days from the date of your order, subject to availability.

Express Courier 1-2 Day Delivery – UK Mainland only - Zones A & B
£4.50 select at the checkout. Sent using express courier.

Next Day Delivery – UK Mainland only - Zones A & B
£8.00 select at the checkout. Sent using express courier, orders must be placed before 3pm for next day delivery, subject to availability.

Saturday Pre 12am - UK Mainland only - Zones A & B
£15.00 select at the checkout. Sent using express courier, orders must be placed before 3pm for Saturday delivery.

Orders must be placed before 3pm for next day delivery and a telephone number supplied, subject to availability.
Please note that predicted delivery times are based on regular trading days Monday to Friday. Public holidays, bank holidays and weekends are outside the usual scope of our dispatch and therefore may incure additional days lead time to your order.

Orders requiring calibration. Whilst we take the greatest care to get all orders dispatched and delivered to you in the stated time frame, orders received late afternoon and requiring calibration may on occasion miss dispatch that day, according to the complexity of the calibration. Be assured they will ship on the next dispatch, this in most cases should not add more than 24 hours to you delivery.

Delivery Surcharges
Because of the high cost of carriage we need to apply a surcharge on all deliveries made in the following regions bringing the carriage charges to:

  • Zones A & B  - Mainland delivery rates apply. 
  • Zone C - Scottish Highlands. 
  • Zone D - Outer Hebrides, Orkney Isles, Shetland Isles, Isle of Man, Scilly Isles, and Channel Islands.
  • Zone E - Northern Ireland
  • Zone F - Republic of Ireland

New Postage Map Sept 2018> 

International delivery

International delivery charges are automatically added to your order at the checkout; you can also use the guide below for a guide on prices. For any questions regarding international deliveries please contact us at

If no shipping option is available to your selected country please call us on +44 (0) 1603 406 148 to purchase your items.