Dangerous point of busbar switching operation and its prevention - News - Global IC Trade Starts Here Free

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The operation of the busbar refers to the power transmission and power failure of the busbar, and the switching of the equipment on the busbar between the two busbars. The busbar is the meeting place of the equipment. There are many connecting components, and the operation workload is large. It must be fully prepared before operation, and the operation is strictly carried out in order.
Potential danger points of busbar operation: First, possible load puller faults; second, relay protection and automatic device switching error caused by mistakes; third, inductive voltage transformers and switch breaks when charging to no-load busbars The series resonance formed by the capacitor.
The correct method for bus operation and the matters needing attention are:
(1) Charging the spare busbar. When the busbar switch is used, the busbar switch should be used to charge the busbar. The charging protection of the busbar switch should be in the input state, and the protection setting time should be adjusted to 0 if necessary. In this way, if there is a fault in the spare bus, it can be cut off by the bus switch to prevent the accident from expanding. If there is no busbar switch, confirm that the spare busbar is in good condition, and the knife gate can also be used for charging. However, when selecting the knife gate and programming sequence, care should be taken not to overload.
(2) In addition to charging with the busbar switch, during the tripping of the busbar, the operating power of the busbar switch should be pulled open to prevent the busbar switch from tripping erroneously, causing a load puller event.
(3) When all the components on one busbar have to be switched to another busbar, there are two kinds of switching sequence. One is to combine the knife gate of one component to one busbar, then pull off another busbar cutter; After all the components are combined in one busbar, all the cutters of the other busbar are pulled apart. This is determined by the location of the operating mechanism (two busbars on one corridor or two corridors) and on-site habits.
(4) Since the voltage transformer of the relay switch to another busbar or busbar is powered off, the voltage circuit of the relay protection and automatic device needs to be converted and powered by another voltage transformer, so be careful not to make the relay protection and automatic device Malfunction due to loss of voltage. Avoid contact failure of the voltage circuit and reverse charging of the unpowered busbar by the voltage transformer, and the voltage loop fuse is blown, causing the relay protection to malfunction.
(5) Pay attention to the influence of the busbar protection when performing the busbar operation, and make corresponding changes according to the busbar protection operation. In the absence of special circumstances during the reverse bus operation, the busbar protection should be in use. The busbar is equipped with automatic reclosing. If necessary after reversing the busbar, the reclosing mode should also be changed accordingly.
(6) When the domestic SW-220 oil switch stops the empty busbar with only the inductive voltage transformer, in order to avoid the series resonance between the parallel capacitance between the switch contacts and the inductive voltage transformer, the busbar stops. Before the electric current, the voltage transformer knife switch should be pulled open or connected to the appropriate circuit in the secondary circuit of the voltage transformer.