1.Product Characteristics New automatic frequency conversion AC power supply, computer processing control and signal processing technology are used to solve the anti-interference problem in the testing process. 400V, 5A high power output, can ignore the power frequency interference of substation. Equipped with micro printer, computerRS232 interface. 2.Product Brief ETCR3300 large grounding resistance tester is a multi-purpose machine for testing power frequency grounding impedance, grounding resistance and soil resistivity of substation grounding network, hydrothermal power plant, microwave station, communication base station and other large grounding networks. The instrument adopts new frequency conversion AC power supply, computer processing control and signal processing measures, which solves the problem of anti-interference in the testing process and simplifies it. The test operation process improves the accuracy and accuracy of the test results, and greatly reduces the labor intensity and test cost of the test personnel. The ETCR3300 grounding resistance tester for large-scale grounding grid uses super-strong automatic frequency conversion anti-interference technology, with 400V, 5A high-power output, it can accurately measure data at 50Hz power frequency under strong interference environment. It is suitable for testing power frequency ground impedance, grounding resistance, auxiliary machine and other power frequency characteristic parameters of various grounding devices.Measure the conduction impedance or resistance between grounding devices.Soil resistivity. Instrumentation basisJJG984-2004 Verification Regulation for Grounding Conduction Resistance Tester, DL/T475-2006 Guide for Measuring Characteristics of Grounding Devices, General Technical Conditions of DL/T845.2-2004 Resistance Measuring Device Part II: Power Frequency Grounding Resistance Tester. 3.Technical Specifications       Product model    ETCR3300 Large Ground Network Grounding Resistance Tester        Impedance measurement range    0 ohm to 200 ohm        Resolving power    0.001 Omega        measurement error    (+2%+0.005)        Resistance to 50 Hz Voltage Interference at Power Frequency    10V        Test current waveform    sine wave        Test current frequency    Automatic 45Hz/55Hz dual frequency,Multiple Frequency Converters for Selective Use        Output current    5A        output voltage    400V        Measurement line requirements    The cross-sectional area of copper cores for current wires is more than 2.0 mm2 and that of copper cores for voltage wires is more than 1.5 mm2.