Product Details

Cable Outer Sheath Fault Tester

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Test Principle

The detection of cable outer sheath faults, like power cable fault detection, generally requires two steps: "preliminary measurement" and "pinpointing." The preliminary measurement (distance measurement) of outer sheath grounding faults typically uses the voltage drop method and the bridge method. Due to the limitations of the bridge method, it cannot test multi-point grounding faults or faults in three-phase cable chain grounding connections. This instrument is designed for the characteristics of outer sheath faults, using the voltage drop method for preliminary measurement of cable outer sheath grounding faults, and then using the step voltage method to accurately locate the fault point. By using two iron ground rods, it finds the lowest potential point in the soil for precise pinpointing. The test current flowing into the ground at the fault point causes the fault point to be a transition point between positive and negative voltage peaks. When approaching the fault point, the step voltage increases; after crossing the fault, the step voltage decreases and the polarity changes. Directly above the grounding fault point, the pointer stops at zero, which is the exact location of the cable fault point. The instrument is used for detecting outer sheath faults of cross-linked cables; it can also be used for detecting faults in buried cables and all-plastic cables (cables without metal sheath); it can also be used for 10KV DC withstand voltage testing of cables or other electrical appliances.Technical Performance

Model: WHT-08

Power output mode: DC and pulsating, 2 modes optional. DC voltage output: voltage adjustable from 0 to 10kV, short-circuit current 50-500mA. DC current output: 50mA-500mA. Voltage comparison method: ±2% L. Pinpointing accuracy: step voltage method precise pinpointing ±30cm.

Main Functions

(1) A powerful supplement to the reflection method, making preliminary measurement results more accurate and reliable.

(2) An effective means to solve faults in PVC cables with poor wave propagation characteristics and low-voltage cables without copper shielding.

(3) The test voltage is subdivided into three levels: 2000V, 4000V, and 10000V, suitable for cables of different voltage levels.

(4) No blind zone in measurement range.

(5) Automatic discharge function after voltage drops to zero.

(6) Suitable for fault pre-location of 380V-220kV high, medium, and low voltage power cables.

(7) Suitable for precise pinpointing of 380-1000V cables using the step voltage method.

(8) Suitable for pre-location and precise pinpointing of outer sheath faults in 66kV-220kV cables.

(9) The WHT-08 high-voltage generator also serves as a cable fault converter, capable of converting difficult high-resistance faults up to 500 megohms into low-resistance faults.

Note: The above information and technical parameters are compiled and released by Yangzhou Darui Electric Co., Ltd.