PRECISE AC/DC LEAKAGE CURRENT TESTER
Features
- The World First High Accurate AC/DC Leakage Current Testers.
- High Sensitive for Low Range Leakage Current.
- Suitable for Measurement of 4-20mA DC Controlled Circuit.
- DC mV Analog Signal Output.
- Lowest Influence from Magnetization & Terrestrial Magnetism.
- Wide Measuring Ranges - up to DC 1000mA & AC 10A.
GROUND FAULT DC CURRENT MEASUREMENT IN PV SYSTEM BY MODEL 730
- About DC Ground Fault Current in PV System
When the ground fault occurs at the DC current side of power conditioner, DC ground fault current will circulate from the earth to the DC current side of power conditioner via grounding line of boosting transformer & AC current side of power conditioner and then, through the inverter switching circuit. Consequently, DC ground fault current will be superposed to AC current and the current disparity will occur at P&N phase by the content of ground fault current. - About Detection of DC Ground Fault Current in Power Conditioner
ZCT built in DC current side of the internal power conditioner is monitoring current difference between P&N phase and power conditioner will stop, when the difference exceeds the limited value. Those limited values are different according to the power conditioner manufactures but they are generally 30mA~100mA. - About Measurement of DC Ground Fault Current by DC Current Clamp Tester
After making artificial ground fault (approx. 12mA), measurements of DC current at three places (grounding line of boosting transformer, DC current side of power conditioner and artificial ground fault point) were implemented by DC clamp tester (M-730).Consequently, the measured values of these three places were almost same, which means that all the DC ground fault current flowed out to AC current end and the current difference of P&N phase at DC current side of power conditioner was almost same as DC ground fault current.
