ZGF-400kV/3mA DC High Voltage Test Set for 220kV Cable and Arrester Testing

The ZGF-400kV/3mA DC High Voltage Test Set is a series-excited, oil-insulated DC high voltage generator designed for field and laboratory testing of 110kV and 220kV class power cables, zinc oxide surge arresters, bushings, transformers and switchgear. It delivers a continuously adjustable 0-400kV DC output at 3mA rated current, with a 0.75 U1mA automatic reference voltage measurement function for MOA (metal oxide arrester) leakage current testing.

Application

DC withstand voltage testing remains the most practical method for evaluating the insulation condition of oil-filled cables, aged XLPE cables where AC testing is not available, and for measuring the 1mA reference voltage (U1mA) and 0.75 U1mA leakage current of zinc oxide arresters. The 400kV/3mA rating covers 220kV arresters and 110kV cable systems with a comfortable margin, while the lightweight modular construction allows the unit to be carried into substations and cable trenches by two technicians.

Main Features

• Continuously adjustable output from 0 to 400kV DC, rated current 3mA
• Automatic MOA testing: measures U1mA and 0.75 U1mA leakage current, calculates the ratio and prints the result
• High stability under capacitive load; ripple factor better than 0.5% at rated output
• Over-voltage, over-current and zero-start protection with automatic trip
• Large LCD display with Chinese/English menu, real-time voltage and current curves
• Integral 0.75 U1mA one-key operation for arrester testing
• Oil-insulated high voltage tank with air-cooled or oil-cooled transformer option
• Portable modular design: HV tank, control unit and connecting cables in separate cases

Technical Specifications

Standard Accessories

• Oil-filled HV generator tank with HV output bushing
• Digital control unit with LCD display and printer
• Discharge rod rated for 400kV
• Micro-ammeter and shielded measuring cable
• Earthing cables and grounding rod
• Spare seals and oil filling funnel
• Operation and maintenance manual in English
• Factory test report and calibration certificate

Test Standards

The set is designed to support testing in accordance with IEC 60060-1 (high voltage test techniques), IEC 60076-3 (power transformer insulation levels) and DL/T 596 (preventive testing of power equipment). For zinc oxide arrester testing the U1mA and 0.75 U1mA procedure follows IEC 60099-5 and GB 11032.

Why choose this set

Every unit is assembled, oil-filled, and run at rated voltage for 1 hour before delivery, with the test waveform and leakage current recorded in the factory report. The control unit stores the last 50 test records, which is convenient for periodic comparison of arrester leakage current on the same site. We supply 220V/50Hz and 110V/60Hz input versions, and can provide a positive polarity output on request.

FAQ

Q: Can the set test 220kV cables?
A: Yes. 400kV DC covers the DC withstand test voltage for 220kV class cables with margin. For very long cable runs the charging current must be checked against the 3mA rating, and we can quote a 5mA model if required.

Q: Is a discharge rod included?
A: Yes, a 400kV rated discharge rod with earth lead is included in the standard scope of supply.

Q: What is the warranty?
A: One year warranty on the complete set, with lifetime technical consulting and spare parts supply for ten years.