Megger ® MIT300 Series

Insulation and Continuity Testers

Megger MIT310 Insulation Teser
  • Extremely easy to use
  • Tough rubber armoured case
  • Self contained protective cover
  • Live circuit warning
  • Weatherproof to IP54
  • Intelligent Safety System for protection.
  • Result storage and downloading
  • Download software included
  • USB interface
Product Description:

Developed, after extensive customer research, specifically to meet the needs of today’s electrical contractors, the new MIT300 range of insulation and continuity testers from Megger is not only durable and easy to use, but also incorporates a comprehensive set of features designed to ensure operator safety, even under conditions of accidental misuse.

The range includes four models, ensuring an exact match for the needs of every user, all of which offer automatic discharge of the circuit after testing, audible and visual warning if the test probes are applied to a live circuit, and a test inhibit feature which operates automatically under live circuit conditions. The units also conform fully to IEC 61010-1 for use in Category III 600V applications, and provide all of the facilities needed to meet insulation testing requirements relating to the current edition of the IEE Wiring Regulations.

In line with other products in Megger’s comprehensive new contractor range, MIT300 insulation testers feature rugged construction, with an impact-resistant rubber-overmoulded case, and innovative circuitry which guarantees high accuracy combined with stability of calibration.

All instruments in the new range provide indication of insulation resistance up to 999Mohms, 200mA continuity testing, a fast-reacting continuity buzzer, and facilities for nulling the resistance of the test leads. The entry-level MIT300 offers insulation test voltages of 250V and 500V, while the remaining models allow testing at 250V, 500V and 1,000V.

In addition to the basic features, the mid-range MIT310 adds a default voltmeter function, while the MIT320 supplements these facilities with an a backlit display, illuminated range panel, insulation limit alarm, resistance measurement, and an adjustable threshold for the continuity buzzer. The MEGIT320 is also supplied with a switched test probe to speed hands free testing.

An illuminated switched test probe is available as an optional extra for use with the MIT320. The MIT310, and MIT320 testers incorporate dual solid-state displays which simultaneously show the test results numerically, and in the form of a moving-arc bar graph that accurately simulates the operation of an analog meter.

All testers come complete with a full calibration certificate. For users who prefer a true analog device, however, Megger is offering the MIT310A which has features similar to those of the MIT310, but with a conventional moving-coil meter movement in place of the digital display.

General Information:
  • Designed to take the bashing that testers receive on site, the Megger MIT insulation testers are rubber armoured. n The rigid display cover folds right out of the way during testing and locks down to protect the display when it is finished.
  • Simple to use:-
  • No buried functions mean it is obvious how to use the Megger MIT.
  • Colour coded ranges help test selection, reducing testing time and help with fault location.
  • A user guide in the lid provides all the basic information. Hands free use:–
  • It hangs comfortably around the neck for hands-free use because the instrument is carefully balanced.
  • Continuity and buzzer testing starts automatically on connection to the circuit.
  • Insulation tests being activated from the instrument or the switch probe, supplied with MIT320 and MIT330 (not suitable for the use with the MIT300 or MIT310).
  • n Both the display and the range selected can be read in the dark because the MIT 320/330 has a backlit display and range selection.
  • Continuity check – prevents a continuity test or buzzer test on a live circuit.
Safety features:
  • To protect the user and the tester from incorrect use the MIT series all have an extensive range of features known as the Megger Intelligent Safety System including:
  • Safety Interlock – prevents unsafe connection of test leads
  • Safe contact detectors – Even if the MIT is connected to a live circuit whilst on continuity setting the tester will remain safe and not be damaged.
  • Live voltage warning – alerts the operator when a circuit voltage over 25 V exists.
  • Safety lockout – Prevents the test from operating when the circuit voltage is >50 V
Insulation Ranges
MIT310, 310A, 320, 330 1000 V, 500 V, 250 Vdc
MIT300 250 V, 500 Vdc
MIT300, 310, 320, 330 ±3%, ±2 digits
MIT310A <2.5% of scale length (or 30% of reading 200 kohm to 10 Megohms)
Measuring Range:
MIT310, 310A, 320, 330, 300 10 kΩ – 999 MΩ on all ranges
Short Circuit Current 1.5 mA nominal
Test Current on Load 1 mA at min. pass values of insulation (as specified in BS7671, HD 384 and IEC 364)
Accuracy: MIT300, 310, 320, 330 ±3%, ±2 digits
Accuracy: MIT310A <2.5% of scale length (or 30% of reading 200 kohm to 10 Megohms)
Measuring Range: 0,01 Ω – 99,9 Ω (0 -50 Ω on analog scale)
Accuracy: MIT300, 310, 320,330
±3% ±2 digits
Accuracy: MIT310A ±2.5% of scale length (or 30% of reading 0.2 ohm to 2 kohms)
Open circuit voltage: 5 V ±1 V
Test current: MIT300, 310, 320, 330 200 – 215 mA
Test current: MIT310A 200 – 250 mA.
Measuring Range: MIT300, 310, 320, 330 10 Ω – 1 MΩ
Measuring Range: MIT310A 0 – 2kΩ (refer to continuity)
Accuracy: ±5% ±2 digits up to 100 k½
Open circuit voltage: <5 V>
Short circuit current 1.5 mA
Measuring Range: 0 – 600 V a.c. (50/60 Hz) or d.c.
Accuracy: MIT300, 310, 320, 330 d.c. or a.c. (50/60 Hz): ±1%, ±2 digits
Accuracy: MIT310A ±2.5% of scale length for 50/60Hz
Default Voltmeter (All modes including OFF)
MIT310, 320, 330 >25 V a.c. or d.c. is applied display will operate as a voltmeter.
MIT300 Beeps and flash ‘V’ on the display
MIT310A All modes including OFF
Auto Shut off (MIT310, 320, 330)
Auto power down operates after 10 minutes if left in standby mode.
pdf_pic Downloads: General Specifications
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Operating Range: -10°C to +60°C Operating Humidity: 93% R.H. at +40°C max. Storage Range: -25°C to +70°C Communications USB interface Environmental Protection: IP54 Fuses Terminals 500 mA (F) 600 V, 32 x 6 mm Ceramic HBC 10 kA minimum. Display shows if fuse is ruptured. Safety Meets the requirements of IEC61010-1 Cat III 600 V phase to earth. Automatic discharge After an insulation test the item under test will be discharged automatically. Any voltage present will be indicated on the display so that the discharge can be monitored. Power supply Battery: 8 x 1,5 V cells IEC LR6 type(AA alkaline). Rechargeable NiCd or NiMH cells may be used. Battery condition is constantly shown on the display as a four-section bargraph. Battery Life 5000 consecutive tests (5 seconds per test) on any test using 2Ah batteries. Weight All units: 980 gms Dimensions All units: 203 x 148 x 78 mm (8 x 5.7 x 3.2 inches) E.M.C. In accordance with IEC61326 including amendment No.1 index web