120W-60KV HVDC Hi-pot Test System

1) Output voltage: 60KV
2) Output current: 2mA
3) Output power: 120W
4) Ripple: ≤1%
5) Current precision: ≤1%
6) Voltage precision: 1% ±1 word
7) Over-voltage set value erro: ≤1%
8) Control weight: 4kg;
9) Voltage-multiple weight: 4kg
10) Voltage-multiple Height: 110*520mm

Application:
1) MOA lightening-arrester HVDC hi-pot
2) HVDC hi-pot and leak current measurement for HV electrical equipment, such as transformer, switchgear, and oil-type power cable
3) Leak current measurement for water-cooling DC power generators
4) High-stability DC HV generators with high-precision DC voltage-divider for DC HV standardization
Main Feature:
1) Co-formed the industry product standards: “ZBF24003-90 Portable DC HV Generator Common Technical Conditions” and
2) “DLT 848.1-2004 HV Testing Equipment Common Technical Conditions, Part One: DC HV Generator”
3) From the first PWM regulated DC HV generator in China developed in 1992, till today,the DC HV generator series has been sold to 1000 customers with 2857 sales volume till the end of 2013
4) DC HV Generators generate: output voltage 40~1200kV, and output current 2~300mA
5) Highest stability could reach ≤0.05%; Ripple≤0.1%
6) Double-stage voltage-multiplier designed for various test precision requirement
7) Controller and voltage-multiplier can be integrated into a single unit (40kV type) for the convenience of field application
8) ZV-B fully-shielded micro-ammeter: digital LCD covered by conductive glass joint with metal shell, test and shielding cable coaxially led out
9) HV-B Infrared micro-ammeter (optional): Infrared connection, auto test individual and total leak current of double arresters
10) Voltage auto-raise/multi-point test (upgraded Z-VII type): pre-set test voltage, test and record leak current on multi-level voltage
11) Voltage-test open circuit protection, ground protection for the safety of operators
12) Can tolerate HV arcing from large-capacity capacitive test object

Question:
During the DC dielectric test of power cable, when the DC voltage increases to a certain value, the breakdown occurs to the cable; but if we cancel the voltage, the insulation restores; the breakdown happens again when apply the voltage again. What kind of phenomenon it is?
Answer:
In terms of fault type, it can be classified into two kinds: flashover and leakage. For the leakage fault, the voltage increases while the leakage current rises. When it reaches a certain value, the system displays the overcurrent or breakdown. For the flashover, however, there is no linear relation between the leakage current and voltage; the breakdown suddenly occurs once increasing to a certain value. The above-mentioned phenomenon belongs to the flashover fault. There are weak points at the insulation or joints but no fixed discharge channels.