Upper isolation upper grounding locking loop and switch cabinet

Abstract

The invention provides an upper-isolation upper-grounding locking loop and a switch cabinet, and the locking loop comprises a power supply device, a live locking device, a live display with a node, anisolation closing switch, an isolation opening switch, and a grounding closing switch, which are sequentially connected in series; the isolation closing switch is connected in parallel with the electrified display with the node, the isolation opening switch is connected in parallel with the grounding closing switch to form a locking loop, the electrified locking device is electrically connected with the electrified display with the node and the power supply device, and the electrified locking device is arranged at a closing tripping device of the circuit breaker mechanism. Whether a line is electrified or not is judged through the electrified displayer with the node, the state position of the grounding isolation switch is judged through a position signal of the grounding isolation mechanism, misoperation of the whole scheme is achieved through the electric and mechanical principle, the device is automatic and reliable, and the five-prevention requirement is met.

Description

technical field [0001] The invention relates to the technical field of ring network cabinets, in particular to an upper isolation and upper grounding locking circuit and a switch cabinet. Background technique [0002] Since the State Grid launched the "12 kV Ring Main Unit (Box) Standardized Design and Customization Scheme (2019 Edition)" standard on September 25, 2019, provincial grid companies in the State Grid area have increased bidding for 12 kV standard solid insulation Ring network cabinets (boxes) and 12 kV standard environmental protection gas insulated ring network cabinets (boxes) have been widely used in the market; refer to figure 1 and figure 2 , but the plan stipulates that the above two ring network cabinets (boxes) are upper isolation upper grounding lower circuit breaker (load switch) scheme, which is different from the lower isolation lower grounding upper circuit breaker (load switch) scheme used by conventional power supply bureaus. The operation proc...

AI Technical Summary

Problems solved by technology

However, when the existing product is applied to the incoming line unit when the upper isolation upper ground lower circuit breaker (load switch) scheme is completed, the circuit breaker is opened after product maintenance or installation before power transmission is completed, and the normal operation process is not continued. Instead of using the gate grounding switch, it directly informs the superior to send power. At this time, the cable room is already charged, and the circuit breaker can continue to operate without electrical and mechanical locking; if the circuit breaker is closed at this time (see image 3 ), it will cause live grounding, forming a ground fault, and the superior trips

The loopholes in the five defenses are formed, which seriously violates the requirements of the five defenses in GB / T 3906, and the grounding switch cannot be closed with power on

Images