The Megger MIT525 is a versatile Advanced range 5 kV insulation resistance tester designed for professionals who require more than basic “go/no-go” testing. It offers high accuracy, enhanced noise immunity, onboard data storage, and connectivity options for streamlined reporting.
With measurement capability up to 30 TΩ, selectable test currents, and additional diagnostic tools such as PDC testing, Ramp tests, and Dielectric Discharge, the MIT525 is an excellent choice for maintenance teams, electrical contractors, and utility engineers needing deeper analysis and flexible data handling.
Why choose the Megger MIT525?
The MIT525 bridges the gap between simplicity and advanced diagnostics. Unlike Essential models, it includes memory storage, USB/Bluetooth® transfer, and enhanced noise rejection (up to 6 mA), making it ideal for environments up to 230 kV.
If your work involves trend analysis, detailed reporting, and high-capacitance assets, the MIT525 provides the performance and tools to do the job efficiently.
Key features
- RE>Act mode – detects reabsorption current to improve accuracy and safety.
- Patented PI predictor (PIp) – speeds up PI testing by predicting results mid-test.
- Measures up to 30 TΩ at 5 kV.
- ±5% accuracy to 1 TΩ at 5000 V.
- PDC (Polarisation/Depolarisation Current) test capability for advanced insulation diagnostics.
- Ramp and Dielectric Discharge testing modes.
- Up to 6 mA of noise rejection for stable readings in higher-voltage environments (up to 230 kV).
- Selectable test currents (1 mA, 3 mA, 6 mA).
- Onboard memory with time/date stamps and USB/Bluetooth® transfer.
- Safety rated CAT IV 1000 V to 3000 m altitude.
- Rugged dual-case design and large backlit colour display.
Built for your environment
The MIT525 is engineered for challenging field conditions, from noisy substation yards to industrial plants. The dual-case design offers drop and impact protection, while dust and moisture ingress protection ensures reliable operation in harsh conditions.Its enhanced noise immunity makes it suitable for higher-voltage environments, and the large colour display ensures test data is easy to read in any light.
Applications:
- Commissioning and maintenance of transformers, switchgear, motors, and generators.
- High-voltage cable testing and fault location.
- Industrial and utility maintenance requiring advanced diagnostics.
- Trend analysis and condition monitoring via stored test data.
What comes with the Megger MIT525?
- MIT525 insulation resistance tester
- Li-ion rechargeable battery (pre-installed)
- Mains power lead
- Test leads rated for 5 kV
- User guide and quick-start lid reference
- Carry-all holdall with removable lid pouch
Specifications
| Product Type |
Insulation Resistance Tester |
| Manufacturer |
Megger Group Limited (UK) |
| Typical Applications |
High-voltage motors, transformers, switchgear, and industrial equipment insulation testing |
| Test Modes |
IR, IR(t), DAR, PI, SV, DD, PDC, Ramp test |
| AC Input Voltage |
90 – 264 V rms, 47 – 63 Hz |
| Power Consumption |
100 VA |
| Battery Type |
10.8 V, 5.2 Ah Li-ion battery (IEC 62133 compliant) |
| Battery Charge Time |
2.5 h (deep discharge), 2 h (normal discharge) |
| Quick Charge |
30 min charge → ~1 h operation at 5 kV with 100 MΩ load |
| Battery Life |
~6 h continuous testing at 5 kV with 100 MΩ load |
| Auto Power Off |
Automatic shutdown after several minutes of inactivity |
| Fixed Test Voltages |
250 V, 500 V, 1000 V, 2500 V, 5000 V |
| User-Defined Voltage |
40 V – 1 kV (10 V steps); 1 kV – 5 kV (25 V steps) |
| Voltage Accuracy |
+4 %, −0 %, ±10 V at 1 GΩ load (0–30 °C) |
| Resistance Range |
10 kΩ – 15 TΩ @ 5 kV |
| Display Range (Digital) |
10 kΩ – 10 TΩ |
| Display Range (Analogue) |
100 kΩ – 10 TΩ |
| Measurement Accuracy (23 °C) |
5000 V: ±5% up to 1 TΩ / ±20% up to 10 TΩ 2500 V: ±5% up to 500 GΩ / ±20% up to 5 TΩ 1000 V: ±5% up to 200 GΩ / ±20% up to 2 TΩ 500 V: ±5% up to 100 GΩ / ±20% up to 1 TΩ 250 V: ±5% up to 50 GΩ / ±20% up to 500 GΩ |
| Current Range |
0.01 nA – 6 mA |
| Current Accuracy |
±5% ±0.2 nA (20 °C) |
| Short Circuit / Charge Current |
1 mA, 3 mA default; 6 mA (mains supply) |
| Capacitance Range |
10 nF – 25 μF (test voltage >500 V) |
| Capacitance Accuracy |
±10% ±5 nF |
| Capacitor Charge |
<3 s/μF at 3 mA to 5 kV |
| Capacitor Discharge |
<250 ms/μF (5 kV → 50 V) |
| Voltmeter Range |
30 – 660 V AC/DC |
| Voltmeter Accuracy |
±3%, ±3 V |
| Timer Range |
Up to 99 min 59 s (15 s minimum) |
| Insulation Alarm Range |
100 kΩ – 10 GΩ |
| Guard Terminal Performance |
Guards current ≥5000× insulation test current at 100 GΩ, 5000 V |
| Memory Capacity |
5.5 h logging @ 5-second intervals |
| Real-Time Output |
1 Hz (Voltage, Current, Resistance) |
| Interface |
USB Type-B, Bluetooth Class 2 |
| Operating Temperature |
−20 °C to +50 °C |
| Storage Temperature |
−25 °C to +65 °C |
| Humidity |
90% RH non-condensing @ 40 °C |
| Maximum Altitude |
3000 m |
| IP Rating |
IP65 (lid closed), IP40 (lid open) |
| Safety Rating |
CAT IV 600 V |
| Dimensions |
315 × 285 × 181 mm |
