EN
MRT-3128 Series High Voltage Insulation Resistance Tester
MRT-3128A / MRT-3128B / MRT-3128C Intelligent Digital High Voltage Insulation Resistance Tester, Multi-Voltage Grade Selection, Supporting IR, DAR, PI & Step Voltage Test for HV Equipment Insulation Condition Assessment.
- Description
- Specifications
- Applications
- Advantages
- FAQ
- Recommended Products
Description
MRT-3128 Series includes three graded models: MRT-3128A (max 5kV DC), MRT-3128B (max 10kV DC), MRT-3128C (max 15kV DC). It is a professional portable high voltage insulation megohmmeter developed for insulation preventive test and condition evaluation of medium & high voltage electrical equipment in power substations, power plants, industrial enterprises, new energy stations and third-party testing laboratories.
The series adopts high-efficiency digital DC boost and high-precision micro-current sampling circuit. It realizes full diagnostic measurement: insulation resistance (IR), dielectric absorption ratio (DAR), polarization index (PI) and step voltage (SV). Independent GUARD shielding terminal effectively eliminates surface leakage interference, improving measurement accuracy under humid and polluted site conditions.
Specifications
| Parameter | MRT-3128A | MRT-3128B | MRT-3128C |
|---|---|---|---|
| Max DC Test Voltage | 5000V | 10000V | 15000V |
| Fixed Voltage Gears | 250V/500V/1kV/2.5kV/5kV | 250V/500V/1kV/2.5kV/5kV/10kV | 250V/500V/1kV/2.5kV/5kV/10kV/15kV |
| Adjustable Voltage | Optional 50V ~ Max Voltage, 50V step | ||
| Resistance Measurement Range | 0.1MΩ ~ 10TΩ | 0.1MΩ ~ 20TΩ | 0.1MΩ ~ 30TΩ |
| Basic Accuracy | ±3% reading ±5 digits | ||
| Max Short-Circuit Current | ≥6mA | ||
| Test Modes | IR, DAR(absorption ratio), PI(polarization index), Step Voltage ramp test | ||
| Terminals | HV, GROUND, GUARD shield terminal | ||
| Display | 5" color capacitive touch screen, CN/EN bilingual | ||
| Data Storage | Built-in memory, thousands of records with timestamp | ||
| Communication | USB 2.0 (U-disk export + PC software) | ||
| Safety Functions | Zero start interlock, HV sound-light alarm, auto discharge, breakdown protection, over-temperature protection | ||
| Power Supply | Built-in lithium battery; AC 100~240V charging adapter | ||
| Continuous Battery Life | ≥8 hours | ||
| Operating Temperature | -10℃ ~ +50℃ | ||
| Humidity | ≤85% RH (non-condensing) | ||
| Enclosure | Shockproof portable reinforced plastic case with handle |
Applications
Core Test Objects
- Power transformers, distribution transformers
- Medium & high voltage power cables, cable joints & terminals
- Motors, generators and rotating electrical equipment
- GIS, switchgear, busbar, current/voltage transformers
- Surge arresters, insulating supports, winding insulation components
Typical Application Scenarios
- Power grid operation & maintenance: routine preventive test, equipment condition evaluation
- New energy power stations: wind turbine, photovoltaic inverter & transformer insulation test
- Industrial & mining enterprises: internal power equipment periodic maintenance
- Third-party testing institutions: engineering acceptance, insulation diagnostic testing
- Power equipment manufacturers: factory quality inspection & type test
Advantages
Compliant with domestic & international test standards
Fully meets DL/T 911, IEC 61557-2, GB/T 1410, test data recognized for metrology acceptance
Graded three-model lineup
5kV /10kV /15kV gradient configuration, match different voltage class equipment, flexible procurement
Complete insulation diagnostic toolkit
IR+DAR+PI+SV multi-mode testing, realize comprehensive insulation aging assessment
Guard terminal anti-interference design
Solve measurement deviation caused by surface leakage under wet on-site conditions
Multi-layer safety protection system
Auto discharge, breakdown protection, high voltage alarm, zero interlock, ensure operator safety
Battery-powered portable design
Suitable for outdoor off-site live-out preventive test without fixed power supply
Complete data archiving solution
Mass storage + PC analysis software + standard report output, meet power management archive requirements
FAQ
Q: How to select among A/B/C three models?
A: General selection principle:
- MRT-3128A (5kV): 10kV level distribution transformer, medium voltage cables, motors below 35kV
- MRT-3128B (10kV): 35kV ~ 110kV transformers, main power cables, conventional substation main equipment
- MRT-3128C (15kV): 220kV/330kV main transformer, long-distance HV cable, high-grade insulation strict evaluation scenarios
Q: What is the function of GUARD shielding terminal?
A: The guard terminal shunts surface leakage current of insulation. When testing under rainy, humid or dirty conditions, surface leakage will cause low reading deviation. Connecting guard wire can bypass leakage current, ensure the instrument only measures volume insulation resistance inside the equipment, greatly improve test accuracy.
Q: Difference between DAR and PI?
- DAR (Absorption Ratio): R60s/R15s, used for medium-short time insulation absorption characteristics, suitable for cables, motors
- PI (Polarization Index): R10min/R1min, reflects deep insulation aging & moisture ingress, mainly for large power transformers
Q: Must discharge after measurement?
A: The instrument has built-in automatic discharge circuit. But for long cables and large capacitive test objects, please wait sufficient discharge time and confirm voltage returns to zero before touching test terminals to avoid residual electric shock hazard.
Q: Standard Package List
Main unit, HV test rod, test leads (HV/Ground/Guard), AC charging adapter, USB data cable, shockproof carrying case, user manual, factory test report, CNAS calibration certificate, PC analysis software. Optional: Extended high voltage test cables, insulating protective gloves, dedicated test fixture.
