Megger MIT420/2 Insulation Tester

📌Overview

Megger MIT420/2 is a CAT IV insulation tester from the MIT400/2 series. The instrument is equipped as standard with 50 V, 100 V, 250 V, 500 V, and 1000 V insulation test voltages and supports Polarization Index (PI) and Dielectric Absorption Ratio (DAR) measurements. Custom continuous adjustable test voltage is also supported (10 V to 1000 V for MIT420/2, in 1 V steps; 50 V to 1000 V for other models in the same series, in 10 V steps).

Compared with the previous MIT400 model, the new model uses feedback voltage regulation technology, controlling test voltage overshoot to within 2% (the industry standard is generally 10% to 20%). The instrument is equipped with a rear stand, a 6-cell battery compartment, and an independent fuse access port. The continuity test has also been upgraded, with a single range and automatic range switching replacing the original multiple resistance ranges, while retaining two test currents of 200 mA and 20 mA.

✅Features

1. Insulation Testing: MIT420/2 provides a maximum test voltage of 1000 V and a measurement range of up to 200 GΩ. PI (Polarization Index) and DAR (Dielectric Absorption Ratio) measurements are supported.

2. Adjustable Test Voltage: MIT420/2 allows the test voltage to be freely set from 10 V to 1000 V in 1 V increments, meeting non-standard testing requirements.

3. Continuity Testing: MIT420/2 features a single automatic range from 0.01 Ω to 1 MΩ, significantly improving testing speed.

4. Voltage Measurement: MIT420/2 measures AC/DC voltage up to 600 V True RMS and features live circuit detection and protection functions.

⚠️Safety Operating Precautions 

1. The circuit under test must be powered off and isolated before insulation testing. Confirm that no voltage is present before connecting the test leads. Although the instrument is equipped with live circuit detection and test lockout functions (insulation testing is disabled by default when the detected voltage is >50 V, and the threshold can be configured), this protection must not be relied upon. The power-off and voltage verification procedures must still be followed.

2. The insulation test outputs high DC voltage. Do not touch the test leads or the conductors under test during testing. After the test button is released, the instrument automatically discharges capacitive loads. For large-capacitance loads, additional manual discharge is recommended to prevent electric shock from residual high voltage.

3. The instrument has a safety rating of CAT IV 600 V and can only be used for measurements on low-voltage source-side circuits not exceeding 600 V. Never use the instrument beyond its rated voltage level.

4. Before use, check the insulation of the test leads and alligator clips for cracks or damage. Do not use damaged test leads. Wearing insulated gloves is recommended during operation.

5. Voltage Selection: MIT420/2 supports adjustable test voltages from 10 V to 1000 V in 1 V increments. Select the test voltage according to the specifications of the equipment under test. Do not arbitrarily select an excessively high test voltage to avoid breakdown of motors, cables, and electronic components.

🔌Technical Specifications

1. Single resistance range：One range fully automatic from 0.01 Ω to 1.0 MΩ.
2. Timed testing：Automatically test to a time limit.
3. High test range：Insulation testing up to 200 GΩ at 1000 V.
4. Test Lock：Holds insulation test on continuously.
5. Buzzer：ON/OFF selected by simple push button.

🏢Contact Information