It is analyzed that when the storage time of the switch spring is greater than the recharge time of the reclosing, when the test is terminated by the permanent fault protection, the recloser will close the circuit breaker after the delay. At this point, the operating mechanism re-storage, the energy storage time is greater than 15s, but the protection has accelerated the tripping of the circuit breaker, the closing circuit is disconnected by the stored energy blocking contact, the TWJ is not excited, the protection is considered to be the closing position of the circuit breaker, reclosing After 15s, the battery is charged. When the energy storage is finished, the closing circuit is connected by the energy storage latching contact, and the TWJ is excited. At this time, the protection considers that the circuit breaker trips, so the circuit breaker is closed by the reclosing, thereby causing In the event of a permanent failure, the circuit breaker repeatedly coincides with the fault, causing an increase in the accident.
This situation is not exposed when the switching spring energy storage time is less than the reclosing charging time, but this is a hidden danger. The measured energy storage time of the spring mechanism is generally 12s. During the process of replacing the batch of circuit breakers, there is a failure of the energy storage motor output, which causes the energy storage time to be too long. In addition, when the DC voltage is lowered, the output of the energy storage motor is also insufficient. In both cases, the circuit breaker is repeatedly overlapped after the permanent fault protection trips.
When the operating mechanism is not storing energy, the operating mechanism is not ready. The charging of the reclosing is meaningless and incorrect. We can learn from the hydraulic operating mechanism in the pressure reduction blocking method. When the operating mechanism does not store energy, use the un-storage contact to start the pressure blocking relay in the operating box to achieve the purpose of locking the reclosing when not storing energy. For example, specifically, the storage tank switch contact (SP1) starts the operation box 2YJJ relay, and the 2YJJ contact is used to feed the protection lock reclosing.
The phenomenon of the reclosing action caused by the local opening of the circuit breaker circuit, for example, protects the reclosing action when the circuit breaker is opened in place. When analyzing the local operation, because the protection operation is not passed, and the protection control circuit cannot be cut off (the SM1 contact has been short-circuited), the protection device thinks that the local opening is the circuit breaker has stolen, so when the protection reclosing is filled The circuit breaker will be closed again when the power is on.
Measure 1 will transfer the local operation circuit, and carry out the opening and closing operation through the operation box manual relay (SHJ) and the manual jump relay (STJ) on the protection screen, which can effectively avoid the reclosing failure. Measure 2, for example, find a pair of contacts on the /remote 0/local 0 switch (SM3). When switching to local control, the contact is closed and sent to the operating box to start the pressure reduction latching reclosing relay (2YJJ). Send a central signal. The purpose of the central signal is to prevent the operator and the maintenance personnel from forgetting to switch the switch to the remote control and to block the reclosing. The author uses this method, as shown in Figure 2. Because it can also share a /270 loop with the un-energy lockout start/pressure reduction latching recloser relay 0 (2YJJ).
When the circuit breaker is closed, the arc-cutting capacitor causes an accidental sound signal. When the circuit breaker is closed, the accident sounds at the end of the energy storage of the operating mechanism. Analysis and as shown, the circuit breaker accident sound is not activated by the TWJ normally open contact and the KK1-3, KK17-19 contact series. When the circuit breaker is closed by KK, the KK1-3 and KK17-19 contacts are connected, the operating mechanism stores energy, the energy storage contact SP1 and the circuit breaker auxiliary contact SP2 are disconnected, the TWJ is demagnetized, and the capacitance control signal circuit diagram C2 and There is 110V voltage on each C3. When the energy storage ends, SP1 closes and shorts C3. Since the voltage on C2 cannot be abrupt, the voltage on TWJ will become 110V, and the voltage of TWJ will become 0V when C2 voltage is charged to 220V. In the process , will cause the TWJ to act instantaneously, and cause the accident sound to send a signal instantly.
Item name: Ferric oxalate pentahydrate
Search number: [CAS 2944-66-3]
Molecular formula: Fe2 (C2O4) 5H2O
Molecular weight: 465.82
Properties: light yellow green crystal or powder; soluble in water and acid; insoluble in alcohol; thermal decomposition to 100 degrees.
Use: used as catalyst, analytical reagent and photographic
Iron Oxalate,Ferric Oxide For Iron,Iron Oxide Ferric Red,For Oxide Hydrates Iron
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