Indoor Medium-Voltage Indicator Without Lock with Relay with Core Phase Function in Switchgear

Indoor high-voltage live display without lock with relay with core phase function

      (1). The function of the high voltage switchboard to prevent stray into the electric gap makes the door of the switchboard locked to the ground switch. That is, it can only be opened after the ground switch is closed. The accident revealed that the five anti-lock devices of the old type of switchboard were imperfect.

      (2) The problem of electrical inspection in high voltage switchgear has been a problem that has troubled the safe production of electricity for many years. The mechanical and locked-in devices of the fully closed five switchgear can not meet the requirements of the safety regulation, such as first checking and then connecting ground line. Because in the performance of power outage work, before the grounding switch must verify that the equipment has no voltage.

          (3) High voltage electric display devices using neon lamps as display elements are widely used in distribution cabinets. After a long period of operation, a high loss of visibility and extensive damage to neon bubbles are found. In order to compensate for the defect, a neon light running / closing switch was installed on the electric display device, which was in a state of turning off at normal times, thus temporarily deactivating the whole high-voltage electric display device. This treatment loses the role of a high-voltage live display device as a monitor for whether the line side is charged.

         (4) The old type of high-voltage electric display device with mandatory electrical latching, which is too simple in principle, consists of half wave rectifying and directly combining the signals from the A, B and C phase sensors to control the latching circuit. In this way, when the system has an anomaly of single phase grounding or absence phase, the drift of the locked-in control voltage can lead to the accident of the electrically connected grounding switch.