High-voltage hipot tester ZGF 60~120kV

portableDC

Product Introduction
The ZGF Integrated DC Hipot Tester is a portable instrument for assessing insulation withstand voltage and measuring leakage current on power equipment. It integrates a high-frequency voltage doubler topology, PWM control and voltage-current dual closed-loop feedback to provide stable DC output with low ripple. The unit combines the host and voltage doubler in one chassis and supports one‑button 0.75U, zero-start boosting and digital over‑voltage setting for field use.

Key Features

• Stable DC output: high-frequency voltage doubler with PWM and V–I dual closed-loop control; ripple ≤0.5%.
• Protection suite: zero-start, over-voltage, over-current and breakdown protection with nanosecond-level sensing.
• 0.75U one-button function for ZnO arrester testing.
• Zero-start boost using imported multi-turn potentiometer for smooth, precise rise from zero.
• Digital over-voltage setting via rotary dial switch for accurate configuration.
• Integrated, compact design: host and doubler in a single portable chassis.
• Critical components: high-performance imported IGBTs and high-frequency HV rectifier diodes; insulated pressure roller for moisture resistance.
• User-friendly panel: clearly labeled controls and logical layout for quick operation.

Technical Parameters

• Models: 60/2, 60/3, 60/5, 120/2, 120/3, 120/5.
• Rated voltage: 60 kV or 120 kV.
• Rated current: 2 mA, 3 mA, 5 mA.
• Rated power: 120–600 W depending on model.
• Weight: ≈9 kg (60 kV series), ≈10 kg (120 kV series).
• Dimensions: 465×390×190 mm (60 kV) / 565×390×190 mm (120 kV).
• Double cylinder height: 440 mm (60 kV) / 535 mm (120 kV).
• Output accuracy (V/I): ±(1.0% reading ± 2 digits).
• Ripple factor: ≤0.5%.
• Operation mode: intermittent, rated load 30 minutes.
• Overload: no-load voltage may exceed +10% for 10 minutes; max charging current 1.25× rated.
• Power supply: AC 220V ±10%, 50 Hz.
• Operating environment: -10 to 40°C; RH ≤85% at 25°C (no condensation); altitude ≤1500 m.

DC Hipot vs AC Withstand Voltage

• Test field: DC provides a constant, non-pulsating electric field; AC provides alternating field (50 Hz or equivalent).
• Portability and weight: HF DC generators are significantly lighter and more portable than power-frequency AC units.
• Power supply: DC systems operate from standard 220 V; AC systems often require high-capacity supplies or generators.
• Damage mechanisms: DC can produce cumulative space-charge effects (affecting XLPE aging); AC tends to cause thermal/carbonization damage at breakdown points.
• Leakage reading: DC leakage in µA reflects moisture and degradation trends; AC leakage in mA requires correlation with dielectric loss (tan δ).

Applications

• Power cable testing: DC withstand voltage and leakage current measurement for XLPE medium/low-voltage cables.
• Insulator and bushing testing: surface leakage measurement to assess moisture or contamination.
• ZnO surge arrester testing: apply DC reference voltage (e.g., U1mA) to detect nonlinear resistor aging.
• R&D and production: factory withstand testing of HV capacitors, HV motors, transformers and related components.

FAQ

• Q: What are common safety hazards during testing? A: High-voltage shock, insulation breakdown, fire and equipment failure; follow safety procedures strictly.
• Q: How does ripple affect tests? A: Higher ripple increases output fluctuation and may cause inaccurate results in precision tests.
• Q: How to choose a DC generator for cable testing? A: Calculate required test voltage and capacity from cable length, conductor section and insulation level with an appropriate safety margin.
• Q: Can a DC generator be used for AC withstand tests? A: Generally no; use a dedicated AC high-voltage generator for AC tests.