Megger MIT525/2-US - Advanced Model Overview

The Advanced series' MIT525/2-US delivers exceptional noise immunity, strong test performance, and enhanced safety, making it a reliable choice for demanding electrical environments. It features a user-friendly custom color display with excellent visibility—even in extreme conditions—thanks to its unbeatable viewing angle. This model provides 250 V, 500 V, 1000 V, 2500V, 5000 V and user defined test voltages. It also supports recording of test results and data transfer to software or mobile apps via USB or Bluetooth Low Energy. The MIT525/2-US enables advanced diagnostic insulation testing, adds extra noise immunity tailored for power distribution settings, and offers full control over output current, allowing users to increase or decrease it as needed.

Features and Specifications

• 10 kV Max. Test Voltage

• 90-264 V rms, 47-63 Hz 100 VA AC Voltage

• 1 mA, 3 mA, 6 mA* user selectable max. current values

• 3 mA noise rejection

• Supports diagnostic and over voltage tests- Pl, DAR, DD, PDC, SV and ramp test

• RE>Act test mode

• Pl predictor function (Pip)

• Bluetooth link for live streaming data to PC and downloading results

• Rapid charge Li-ion battery pack

• Operate and charge battery from AC source (except during test)

• Advanced memory with time/date stamp

• DC and AC voltmeter (30 V to 660 V)

• Large custom color display with backlight

• Safety rating: CAT IV 600 V, CAT IV 1000 V

• Unique dual-case design - additional user protection

Megger’s RE>Act Test Mode

This feature will revolutionize the reliability of your measurements. When insulation testing it is essential that any re-absorption current from the insulation under test is fully discharged before starting the test. Remaining absorption current, depending on polarity, can result in IR measurements that are falsely high or low, with the potential to incorrectly pass any failing insulation. The RE>Act mode not only measures this reabsorption current but also provides an indication to the user of the impact that it will have on the instruments' measurement range and accuracy.

Megger’s PI Predictor for Polarization Index (PI) Test 

The Polarization Index (PI) test is a widely used time-resistance method essential for maintaining large electrical equipment. It delivers reliable, temperature-independent results that guide maintenance decisions, but its main drawback is duration—10 minutes per test, which can extend to 30 minutes for three-phase systems or 50 minutes for multi-core cables.

Megger’s PI Predictor significantly shortens this process by using an algorithm to forecast the 10-minute result from the early part of the insulation resistance curve. Predictions start after about 3 minutes and typically conclude within 3-7 minutes, averaging 5 minutes. Fully compliant with PI standards, the PI Predictor ensures results are expressed as a 10-minute test, enabling accurate historical comparisons while minimizing downtime.

GUARD Terminal Eliminates Surface Leakage Currents

All Megger 5 kV, 10 kV and 15 kV insulation testing test leads are fitted with unique locking HV plugs and non removable test clips. This reduces the likelihood of a plug or clip inadvertently losing electrical connection and the capacitance of a long cable remaining lethally charged.

Shown left, the arrows on the plug finger guard on the instrument demonstrate locking. Twist 90° to unlock. In addition, for the same reason, the test clips are not removable from the test lead. Note, terminals are designed to accept only genuine Megger test leads.

GUARD Terminal Performance

When measuring an insulation resistance of 100 GO at 5000 V the tester can guard out current IG at least 5000 times the insulation test current IL with a maximum additional resistance error of 1%.

Megger's Series of Insulation Resistance Testers

Megger’s selection of 5, 10, and 15 kV insulation testers are known for their durability, longevity, and precision. With a wide array of models available among several series from essential, advanced to expert, you're guaranteed to find one that suits your specific needs perfectly. A sampling chart of differences is below, see data sheet for full table of features.

Software Support

• CertSuite Asset Lite (Free)

• CertSuite Asset Compatible (Licensed)

• Power DB Lite (Free)

• Power DB Advanced or Pro Support (Licensed)

CertSuite Asset is an online electrical asset testing and reporting solution designed for industrial environments. It supports testing for power cables, generator motors, substation transformers, and more, offering real-time graphing and reporting during tests. The software works both online and offline, syncing data to a secure cloud once connectivity is restored, and is accessible via any browser or through an Android app.

The Megger PowerDB Pro asset and test data management PC software is a powerful software package that provides you with data collection and management for all of your acceptance and maintenance activities. With PowerDB Pro, an entire organization’s data and test results can be synchronized into a single database, scalable to Microsoft SQL Server, for easy retrieval and review. Also allows customization of reports for presentation.

Applications for the MIT Insulation Resistance Testers

Suitable for varied testing reasons:

• During manufacture, as part of quality inspection or safety checking prior to shipment

• Prior to product/asset shipment to provide benchmark measurements

• On site inspection, comparing to benchmark results, to ensure everything is good before installation

• Checking after installation of a new asset

• During maintenance to drive predictive maintenance

• Following repair prior to powering up

Suitable for varied environments:

• Production line

• On construction sites

• Industrial locations

• Power distribution

Suitable for many assets:

• Cables of all types

• Power transformers

• Measurement transformers

What's in the Box

• MIT525/2-US ADVANCED 5kV Insulation Tester

• Power Lead

• USB cable

• Lead set 3kV 3 X 3 M

• Medium clips

MIT Advanced Series Insulation Tester FAQ

What additional features are included in the MIT525/2 Advanced model?
The Advanced range models also add additional noise immunity for power distribution environments, and the ability to either increase or decrease the output current.

What diagnostic test does the Advanced Series range support?
All Advanced models support a full suite of diagnostic test modes, including IR, DAR, PI, DD, step voltage, ramp, and PDC (with software). These tests are essential for in-depth insulation condition assessment on critical assets like transformers, cables, motors, and switchgear.

Does the MIT525/2 (5 kV) Advanced insulation resistance tester record test results?
Yes, it records test results, transfers results to a software/mobile app (via USB or Bluetooth LE), and also provides the benefits of more diagnostic insulation testing. The results can be also exported directly to PowerDB or CertSuite to support documentation, compliance, and long-term record keeping.

Is the Advanced Series suitable for noisy environments?
Yes, the Advanced models offer 6 mA of noise immunity, making them suitable for environments up to 230 kV. This ensures stable, reliable results in moderately noisy conditions, such as industrial plants or distribution-level substations. For extreme electrical noise or testing above 230 kV, the Expert range is recommended.