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Lightning protection and grounding assembly, due to various issues such as aging equipment, poor body performance, overdue service, and operation and maintenance to get rid of in the future, many problems such as poor schemes, consistent layout, and poor construction quality have been added to the field improvement, which endanger the power grid at all times. Comfortable operation. The above takes care of some things that lightning protection and grounding should be: ground network excavation. Local transformer substations have a long operating time, and some even run as long as 37 years. The test and inspection staff can shake the ground resistance every year during the year to see if they can meet the requirements and issue test reports. However, the lightness of the test data is rarely explained. Variety.
The structure is open to ground. There are four kinds of error scenarios: one of the busbar frames is grounded through the main reinforcement of the cement rod. Secondly, the metal structures holding the hook string are used as channels between the switch frames, and grounded by the bolts at the joints. The third lightning rod leads down through the main reinforcement of the cement rod. The other four lightning rods were placed in the reinforced cement pier with another down conductor. The gap is arranged horizontally. The original 110kV transformer neutral point discharge gap is mostly installed vertically. Few years of operation have proved that vertical installation of the discharge gap has many disadvantages. When it encounters a humble image, it is easy to form an icicle, which can be effective and affect comfort. Neutral grounded down conductors are stably grounded at two points on the main network. . The neutral point of the transformer should have two grounding conductors that are different from the main grounding network, and each grounding conductor should meet the requirements of thermal fluctuations. The main equipment and equipment structure should have two grounding conductors. The grounding down conductors connected at different locations should meet the requirements of thermal fluctuations, and the connection leads should also be convenient for current search and testing. The transformer's neutral point is single-grounded. Once the connection cable has a problem, the device will run off the ground.
The extension ground network and the original ground network should be connected at multiple points. Over time and the erosion of the grounding resistance of the grounding network, the grounding resistance will be tampered, and some even exceed the standard. In order to reduce the mains grounding resistance, it is a good action to lay another grounding network. At the end of the main network, a single delay in grounding was added, and the main network grounding resistance was high and low.
The comfortable distance between the main net and the lightning rod net. Over time, the grounding resistance of the main network and the lightning rod network will always be added, and some even exceed the standard. It is imperative to lay the corresponding grounding network with low resistance. Straight-fit the 'Trinity' wiring situation. Lightning arresters are not installed on the high-voltage side of the substation (because the incoming line is installed and the protection distance of the arrester does not exceed the large electrical distance between the lightning arrester and the transformer, so it is omitted in the plan). The low-voltage side neutral point and the transformer metal case are grounded all the way, forming the so-called 'Trinity' wiring situation of the transformer. The low-voltage side arrester leads the down-conductor to hold the transformer's casing as a discharge channel for the arrester, which is not in line with technical requirements.