question 2: where is the need for indoor grounding bus? Bus operation refers to the power supply and power failure of the bus, and the switching of equipment on the bus between two buses. Busbar is the meeting place of equipment, with many connecting elements and heavy workload. Whether it is normal spring and autumn maintenance work or bus reversing work after an accident, full preparations must be made before operation, and attention should be paid to the changes of other conditions such as operation mode during operation. Bus reversing operation is a very frequent and complicated operation for substation, which is a little careless. Misoperation accidents will occur. 1 Danger points of normal bus reversing operation 1.1 General principles of normal bus reversing operation The bus must first close the bus coupler circuit breaker and remove the control fuse, so as to ensure that the bus disconnector meets the requirements of equipotential operation when it is connected and disconnected. In the process of closing and pulling the bus disconnector, if a big spark may occur, the nearest bus disconnector of the bus coupler circuit breaker should be closed first; The operation sequence of the switch is the opposite; Minimize the potential difference when operating the bus disconnector. Before pulling the bus coupler circuit breaker, the ammeter of the bus coupler circuit breaker should indicate zero; At the same time, the auxiliary contact and position indicator of bus disconnector should be switched normally. In case of "leakage" of equipment, or reverse charging from the secondary side of bus voltage transformer, causing accidents. In the process of bus inversion, bus differential protection should generally be put into operation if it is not damaged. At the same time, the closing of non-selective switch of busbar differential protection and the switching of low-voltage blocking busbar differential protection linking piece should be considered. If the bus coupler circuit breaker cannot be used for some reason, the bus disconnector must be used to pull and close the no-load bus, and the secondary side of the bus voltage transformer should be disconnected first to prevent the fuse of the bus voltage transformer from fusing or the automatic switch from tripping. 1.2 Analysis of dangerous points during operation and control measures When the bus is inverted, after the bus coupler circuit breaker is closed, the bus coupler DC control circuit fuse is forgotten due to technical failure or negligence. Under normal circumstances, the operation can be smoothly carried out to the end. However, in case of misoperation, protection action or DC two-point grounding in the operation process, the bus coupler circuit breaker will be disconnected at this time, and the voltages of the two buses are not equal. At this time, closing the first group of bus disconnectors or pulling the last group of bus disconnectors is essentially to use the bus disconnectors to connect or disconnect the two groups of bus system loops. The effective value of the loop voltage difference of 85U is equal to the actual difference between the power supply voltages of two buses, which can reach hundreds of volts or thousands of volts. When the bus circuit breaker is disconnected, the bus disconnector is often unable to be opened due to the large current in the closing loop and the high voltage difference in the opening loop, resulting in bus short circuit. Control measures: The bus coupler operation is a typical operation, and it must be held by a careful attendant with high technical level, rich experience and skilled business before operation. In addition to charging with the bus coupler circuit breaker, the operating power supply of the bus coupler circuit breaker should be opened during the bus trip to prevent the bus coupler circuit breaker from tripping by mistake, resulting in the event of pulling the disconnector with load. In the field operation procedures, it should be carried out according to the following steps: ① closing the bus coupler circuit breaker; (2) Remove the fuse of DC control circuit of bus coupler circuit breaker; (3) check whether the bus coupler circuit breaker is closed, these three are important safety technical measures necessary for realizing equipotential operation of inverted bus, which should be written into the regulations, so that the attendant can master it skillfully and make no mistakes during operation. When the bus is inverted, an accident of pulling the disconnector with load occurs at the wrong interval, or when the bus coupler circuit breaker is pulled before the bus is inverted, it is not determined or checked again that all the equipment has been inverted on the running bus, and the ammeter of the bus coupler circuit breaker is not checked to indicate zero, so the bus coupler circuit breaker is pulled. In case of equipment leakage, it will cause a power outage accident. Control measures: Strictly standardize the switching operation system, strictly implement the reciting system, and do not operate until the equipment is correct, and do not miss or jump items during operation. After each operation, check that it is in good condition, tick "√" on one operation, carefully review it after operation, and then operate the next one. Electrical, electromagnetic and mechanical locking devices are installed between the disconnector, grounding switch and circuit breaker to prevent misoperation. When switching, if the locking device fails or the disconnector and grounding switch cannot operate normally, the position and state of the corresponding circuit breaker and disconnector must be checked in strict accordance with the requirements of locking, and the locking can only be lifted after verification. When the voltage circuit of relay protection and automatic device needs to be switched to another voltage transformer for power failure due to equipment switching to another bus or the voltage transformer on the bus, there may be two dangerous points at this time: ① the relay protection and automatic device will malfunction due to voltage loss due to poor contact of the voltage circuit, and the voltage circuit fuse will be blown due to secondary charging of the voltage transformer to the dead bus, resulting in relay ...... >; >
question 3: what is the difference between indoor and outdoor grounding buses? Outdoor is zero line, indoor is ground line.
grounding wire: grounding wire is a wire directly connected to the earth, which can also be called a safe return line. When it is in danger, it directly transfers high voltage to the earth, which is regarded as a lifeline. Due to poor insulation performance or humid environment, the shell of household electrical appliances will have certain static electricity, and in serious cases, electric shock accidents will occur. In order to avoid accidents, a wire can be connected to the metal shell of the electrical appliance, and the other end of the wire can be connected to the earth. Once the electrical appliance leaks, the grounding wire will bring static electricity to the earth to release the stare. In addition, it is important for electrical maintenance personnel to use the soldering iron to weld the circuit, and sometimes the integrated circuit in the electrical appliance will be damaged because the soldering iron is charged. In electrical appliances, grounding wire is a line that is connected to the shell of electrical equipment and other parts to lead out unsafe charge or leakage current caused by various reasons in time.
Question 4: What is the grounding bus? The grounding bus is the general wiring bus connecting all grounding wires, and the other end is directly connected to the grounding device. The material is generally hot-dip galvanized flat steel or copper.
question 5: what does outdoor grounding bus laying mean? it means installing outdoor grounding bus. Outdoor grounding bus is flat steel (―― ―5x5) or round steel 1 connecting vertical grounding bodies
Question 6: How to calculate indoor grounding bus for lightning protection grounding? It depends on the distance, the number of grounding items, etc., generally 16 or 25, but not less than 16, for example, there are 16 street lamps on a street lamp. Their grounding is respectively connected to the ground wire diameter of the bus bar .5. Then the bus with 25 is almost the same. What questions can be asked
Question 7: Lightning protection projects, what are indoor grounding buses and outdoor grounding buses, and how to calculate them? There are indoor grounding buses and outdoor indoor grounding buses in every lightning protection project: For civil buildings, indoor grounding buses are generally used in high and low voltage distribution rooms or generator rooms. For equipment grounding.
outdoor grounding bus: mainly horizontal artificial grounding body.
calculated according to the natural along the meter.
every lightning protection project does not necessarily have indoor grounding bus and outdoor.
question 8: are the grounding bus and the flat iron the same? There are several types of grounding buses, such as galvanized flat steel, galvanized round steel and yellow-green special grounding conductor. It is generally used for the connection between the grounding trunk line and the grounding module, depending on what materials are given in the design drawing.
question 9: what's the difference between grounding bus and grounding electrode? Grounding electrode is a grounding device buried underground, and grounding bus is a connecting wire connecting grounding electrode and equipment.
Question 1: Does anyone know what a lightning-proof grounding bus is? A bus connected to the earth pole is a lightning-proof grounding bus.
in modern grounding technology, the lightning protection grounding bus bar is basically replaced by the column reinforcement of the building.
electric power and telecommunications. In the old building, you can see a long galvanized steel bar leading from the roof to the ground, which is the lightning protection grounding bus.