Megger MIT1025/2 MIT Series Insulation Resistance Testers

Megger MIT1025/2 is a 10 kV insulation resistance tester from the Advanced range, designed for diagnostic testing and maintenance of high-voltage electrical equipment including transformers, motors, switchgear, and cables in environments up to 230 kV . This instrument is part of Megger's Advanced series of 5 kV, 10 kV, and 15 kV testers, offering comprehensive diagnostic capabilities combined with data management features .

Now 25% smaller and 35% lighter than previous models, the MIT1025/2 delivers laboratory-grade insulation testing in a rugged, field-ready package .

Key Features

Feature Description

Maximum Test Voltage 10 kV

Maximum Resistance Measurement 20 TΩ (20,000 GΩ)

PI Predictor™ Patented technology predicts 10-minute PI values in 3-5 minutes, cutting test time by up to 50%

RE>Act™ Mode Enhanced test mode that monitors reabsorption current to ensure accurate measurements and prevent dangerous return voltages

Noise Immunity 6 mA interference rejection (from 960 V to 10 kV) for stable measurements in electrically noisy environments

Diagnostic Test Suite IR, IR(t), DAR, PI, DD (Dielectric Discharge), SV (Step Voltage), Ramp, and PDC (with software)

Data Management Built-in memory with date/time stamp; data export via USB or Bluetooth® Class 2

Dual Power Supply Rapid-charge Li-ion battery + AC mains operation (even with dead battery)

Safety Rating CAT IV 600 V up to 3000 m altitude

Dual-Case Design IP65 rating when lid closed; rugged dual-layer construction for field protection

Technical Specifications

Insulation Testing

Parameter Specification

Fixed Test Voltages 500 V, 1000 V, 2500 V, 5000 V, 10,000 V

User-Defined Voltage 100 V to 1000 V in 10 V steps; 1000 V to 10,000 V in 25 V steps

Test Voltage Accuracy +4%, -0%, ±10 V nominal at 1 GΩ load (0°C to 30°C)

Resistance Range (Digital) 10 kΩ to 20 TΩ at 10 kV

Resistance Range (Analog) 100 kΩ to 10 TΩ

Resistance Accuracy (23°C) :

Test Voltage ±5% Accuracy Range ±20% Accuracy Range

10,000 V Up to 2 TΩ Up to 20 TΩ

5,000 V Up to 1 TΩ Up to 10 TΩ

2,500 V Up to 500 GΩ Up to 5 TΩ

1,000 V Up to 200 GΩ Up to 2 TΩ

500 V Up to 100 GΩ Up to 1 TΩ

Current Measurement

Parameter Specification

Current Range 0.01 nA to 6 mA

Current Accuracy (20°C) ±5% ±0.2 nA at all voltages

Short Circuit/Charge Current 1 mA, 3 mA (default), 6 mA at 5 kV/10 kV/15 kV (6 mA only from mains supply)

Capacitance Measurement

Parameter Specification

Capacitance Range 10 nF to 25 μF (with test voltage set above 500 V)

Capacitance Accuracy ±10% ±5 nF

Capacitor Charge Time <5 s/μF at 3 mA to 10 kV

Capacitor Discharge Time <250 ms/μF to discharge from 10 kV to 50 V

Voltage Measurement

Parameter Specification

Voltmeter Range 30 V to 660 V AC/DC, 45 Hz to 65 Hz

Voltmeter Accuracy ±3% ±3 V

Guard Terminal Performance

Parameter Specification

Guard Performance IG ≥ 5000 × IL at 100 GΩ / 5000 V with maximum error of 1%

Noise Immunity

Parameter Specification

Interference Rejection 6 mA from 960 V to 10 kV

General Specifications

Power Supply

Parameter Specification

Battery Type 10.8 V, 5.2 Ah Li-ion (meets IEC 62133:2003)

Battery Life 4.5 hours (typical) continuous testing at 10 kV with 100 MΩ load

Battery Charge Time 2.5 hours (deep discharge), 2 hours (normal discharge)

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

Timing and Memory

Parameter Specification

Timer Range Up to 99 minutes 59 seconds (15 second minimum setting)

Memory Capacity 5.5 hours logging at 5 second intervals

Real-Time Output 1 Hz output readings (V, I, R)

Environmental Specifications

Parameter Specification

Operating Temperature -20°C to +50°C

Storage Temperature -25°C to +65°C

Humidity 90% RH non-condensing at 40°C

Maximum Altitude 3000 m

IP Rating (Lid Closed) IP65

IP Rating (Lid Open) IP40