When performing withstand voltage tests on medium and low voltage cables in the field, power-frequency test equipment is bulky and inconvenient to transport, while DC testing struggles to reveal insulation defects in XLPE cables. When selecting equipment, procurement personnel often need a very low frequency withstand voltage test device that is easy to carry on site and offers controllable waveform quality.
The output waveform distortion of this device is controlled at ≤3% of full scale + 0.5 kV, and the test voltage waveform quality meets the needs of on-site interpretation. The meter accuracy is Class 1.5, with intuitive readings that facilitate recording and comparison by test personnel. The output frequency can be selected as 0.05 Hz or 0.02 Hz, adapting to the test capacity requirements of cables of different lengths.
The equipment supports indoor and outdoor use, with an operating temperature range of -10°C to +40°C and humidity ≤85%, meeting the on-site conditions of most substations and cable trenches. The overall structure is designed for portability, suitable for manual transport to the test point after vehicle transportation.
During selection, the required test capacity should be calculated based on the voltage level, length, and capacitance of the cable under test, and then the output frequency and rated voltage should be selected accordingly. For both acceptance tests and preventive tests, it should be confirmed that the equipment capacity has a margin, and whether the meter accuracy and waveform specifications meet the test procedures of the organization should be verified. Equipment parameters are subject to the factory technical documents; before procurement, it is advisable to request a complete parameter table and check each item.
