The use of capacitive current measuring instrument technology parameters

Automatic capacitive current tester by Fourier algorithm filter voltage to measure the effects of power frequency interference, and calculate the output signal amplitude and phase, and measured results is obtained. This method greatly reduces the 50 hz frequency interference signal to measure the impact of using large screen LCD and Chinese menu, simple operation, and small volume, light weight, easy to carry for outdoor work, simple wiring, test speed, high accuracy data, greatly reduce the labor intensity of the test personnel, improve the working efficiency.

the technical index of the fully automatic capacitive current tester

1. Measuring range: capacitive current 1 ~ 500 a 0 ~ 250 & mu; F

2。 Measurement error: & le; Reading 5%

3. Injection signal frequency: 10 hz ~ 100 hz

4. Working temperature: - 10 ℃ to 50 ℃, humidity: 0 ~ 80%

5. Working power supply: AC 220 v & plusmn; 10% 50Hz± 1Hz

　　6. Dilettante size: 350 mm & times; 200毫米× 150mm

　　7. Instrument weight: 5 kg

purpose and characteristics of automatic capacitive current tester

: automatic capacitive current tester for distribution network voltage grade 6 kv and 10 kv, 35 kv medium voltage distribution network neutral point grounding system. At present, our country the power of the power distribution system neutral point is not earthed directly, so the current through the fault point when the single-phase grounding line is the actual circuit of capacitance of capacitive current. According to statistics, much of the power distribution network fault is due to the large line when the single-phase grounding capacitance rate caused by the arc to themselves. Therefore, our country's power requirements when 10 kv, 35 kv system capacitive current greater than 30 respectively a and 10. A, shall furnish arc suppression coil to compensate capacitive current, this requires the distribution network of capacitance current measurement to make a decision.

in addition, the distribution of earth capacitance and the parameters of the PT can produce PT ferromagnetic resonance overvoltage, PT resonance will happen in order to verify whether the power distribution system and what the nature of the resonance, also must be accurate measurement of capacitance values of the distribution network. Traditional method of capacitive current measuring distribution network with single phase grounding of metal direct method and indirect measurement method and capacitance, all these methods will be exposed to a device, thus test danger, complex operation, low working efficiency shortcomings.

automatic capacitive current tester is the attention of the operating point of the

before using, the instrument must be reliable grounding.

low must be disconnected when the system is neutral on the compensating device ( Such as arc suppression coil) 。

low for a high resistance harmonic elimination device installed on the PT neutral PT group, harmonic elimination device must be measured again after short sub.

if two bus system on the PT secondary winding is parallel operation, secondary winding should be run into solitary way, after the measurement again.

if PT open delta connection load ( Such as harmonic elimination device) Impedance is less than 100 ohms, the load should be disconnected before the measurement.

low automatic capacitive current tester can only from electromagnetic PT secondary side measurement of capacitive current, not from the capacitive voltage transformer ( CVT） The measurement.