Multifunctional testers

MI 3125BT is the ideal instrument for engineers who perform high volume testing or work regularly on TT and TN systems. Containing all necessary tests for installation safety testing, MI 3125BT offers the brand new ability to test B-type (DC sensitive) RCDs. COMBO contains integrated characteristics of fuses and RCDs (including EV type) for the evaluation of line/loop impe-dance results. The bright graphic display with backlight ensures that results, indications, measurement parameters and messages are clear, visible and easy to read. The red and green LEDs on either side of the display provide a clear PASS/FAIL evaluation of test results. Each test has its own individual help screen describing how to connect the instrument into the installation and how to perform a measurement. All the results can be quickly saved and referenced on the instrument and then downloaded via the MESM software.

Standards applied

  • AS / NZ 3760
  • AS / NZ 3018
  • AS / NZ 3017
  • VDE 0413
  • VDE 0100
  • HD 384
  • BS 7671 17th EDITION
  • IEC/EN 60364 series
  • IEC/EN 60364-6
  • IEC/EN 60364-4-41
  • IEC/EN 60755
  • IEC/EN 61008
  • IEC/EN 61557 series
  • IEC/EN 61557-1
  • IEC/EN 61557-2
  • IEC/EN 61557-3
  • IEC/EN 61557-4
  • IEC/EN 61557-5
  • IEC/EN 61557-6
  • IEC/EN 61557-7
  • IEC/EN 61557-10
  • IEC/EN 61010 series
  • IEC/EN 61010-1
  • IEC/EN 61326 series
  • IEC/EN 61326-1

Measuring functions

  • Insulation resistance with DC voltage;
  • Continuity of PE conductors with 200 mA test current with polarity change;
  • Continuity of PE conductors with 7 mA test current (continuous measurement) without RCD tripping;
  • Line impedance;
  • Loop impedance;
  • Loop impedance with Trip Lock RCD function;
  • TRMS voltage and frequency;
  • Phase sequence;
  • RCD testing (general and selective, type AC, A and B);
  • Earth resistance (3-wire method).

Key features

  • LED Pass/Fail indicators: two LED indicators for PASS / FAIL evaluation of test results are placed on both sides of the LCD
  • Help screens: instrument comes complete with built-in help screens for referencing on site.
  • Earth resistance measurement: instrument performs 3-wire earth resistance testing with two additional rods.
  • Built-in fuse tables: this unique feature allows automatic evaluation of the line / loop impedance compared to the regulations.
  • Online voltage monitoring: monitors all 3 voltages in real-time.
  • Upgradeable: if changes occur to the regulations, upgrades can be made to the firmware to keep the instrument up to date.
  • Polarity swap: automatic polarity reversal on continuity test.
  • Insulation range: wide range of insulation test voltages from 50 V to 1000 V, reading up to 1000 MΩ.
  • Trip Lock function: Zs (RCD) function performs a loop impedance test without tripping the RCD.
  • Multi-system testing: tests on single and multiphase TT and TN systems.
  • Built-in charger & rechargeable batteries: unit has a built-in charging circuit and comes complete with a set of rechargeable NiMH batteries.
  • RCD auto: automated RCD testing procedure significantly reduces test time.
  • B type RCD testing is supported.
  • BT connectivity: it enables BT communication with Android tablets and smart phones via built-in BT.
  • PC SW Eurolink PRO included in the standard set enables downloading of test results and parameters and creation of test reports.

Technical data

  • Dimensions: 140 x 80 x 230 mm
  • Mass: 1.0 kg

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General Purpose

  • System maintenance




Download type File name language Version Release date Notes File type File size View online Download
Datasheet PC SW EuroLink PRO en 1.0 13.03.2014 pdf 915.07 KB
Datasheet MI 3125BT COMBO uk 2018 04.10.2018 Single leaflet pdf 531.06 KB
Datasheet Brochure_A_1532_EVSE_MI_3152_MI_3125BT uk 2018 16.11.2018 pdf 3.23 MB
Manual MI 3125BT COMBO uk 2.3.2 26.06.2019 20 751 577 pdf 2.51 MB Login
PC Software Metrel ES Manager Multi-Language 18.07.2019 Readme zip 226.11 MB Login
PC Software EuroLink PRO UK uk 5.17 18.03.2019 zip 29.72 MB Login