Cables are a vital component in power transmission systems. However, as they are used, the insulating part of the cable sheath can become worn out over time. This loss may seem insignificant, but in reality it carries a huge risk. Once the metal sheath has multiple points of grounding, it can cause the generation of circulating currents in the sheath, which in turn increases the sheath loss, which not only affects the current-carrying capacity of the cable, but also may lead to cable burnout in serious cases, and even cause fires and power system malfunctions.
The main duty of cable sheathing is to protect the conductor inside the cable from the damage of external factors, and at the same time ensure the stable transmission of electricity. When the insulating properties of the sheath are degraded, its protective effect is greatly reduced. For example, the intrusion of moisture, humidity or chemicals may lead to further deterioration of the insulation and accelerate the corrosion process of the metal sheath, resulting in the formation of multi-point grounding. The consequences of multi-point grounding should not be underestimated. It will make the original should be evenly distributed current becomes concentrated, resulting in local overheating, this local overload will not only reduce the effective service life of the cable, but also may cause damage to the internal structure of the cable, resulting in short circuits and other serious consequences.
In addition, due to the increase in circulating current, it will also make the overall energy consumption of the cable increase, which undoubtedly increases the operating costs. In order to ensure the normal operation of the cable and the safety and stability of the entire power grid system, it is particularly important to do a good job of cable detection and protection.
Modern testing technology can monitor the operating status of cables in real time and detect abnormalities in a timely manner. By means of ring current detection, partial discharge detection and temperature monitoring, potential insulation problems can be effectively identified and evaluated, and necessary maintenance measures can be taken. DX-DLS100-HL cable sheath ring current online monitoring device, that is, high-voltage cable sheath ring current device, through the CT inductance power, photovoltaic power to maintain the working power, can be externally grounded ring current sensors in the number of three or more, can detect the real-time grounding cable ring current data, and through the fiber and 4G/GPRS/RJ45 real-time transmission of data to the monitoring center, the monitoring center of electronic mapping The electronic map of the monitoring center shows the specific location, so that the line maintenance personnel at any time to grasp the status of outdoor power cables, targeted maintenance.
