Maintenance of ring main unit equipment

Daily Maintenance of Ring Main Unit Equipment

(1) Daily spot check
① Cabinet body: no deformation, dirty.
Cabinet door: no opening, gaps.
Cabinet top: no foreign objects, leakage.
Observation window: no broken glass
② Charged display device: cyclic flashing, normal display.
Ammeter: normal in current range.
Isolated knife switch: no overheating, discolouration at static and dynamic knife contact
High-voltage fuse: no overheating, discolouration
(2) Daily tidying up.
① Wipe the top, body and glass window of the ring network cabinet during inspection
② Keep the insulation board clean and tidy and free of dust

Secondary Maintenance Procedures of Ring Main Unit Equipment

(1) Daily maintenance.
① Wipe the top of the ring network cabinet, cabinet body and glass window.
② Visual inspection: the charged indicating device works normally.
Cabinet lighting: no loose bulbs and reliable wiring connections.
Cables: no loose overheating.
Instrument room fuse: no fused fuse, overheating
Instrument room terminals: wiring is firm and not off
③ Daily maintenance cycle: 1 time/day
(2) Secondary maintenance
① Load switch of ring network cabinet: fasten the connecting screws and blow the dust
② Inlet and outlet terminals: fasten the connecting screws and blow the dust
③ Fuse: blowing dust
④ High-voltage current transformer: fasten the connecting screws and blow the dust
⑤ Maintenance cycle: 2 times/year

Simple Exception Handling of Ring Main Unit Equipment

(1) No display on the current meter of the ring network cabinet.
① Check whether the control fuse is damaged
② Check whether the secondary control line is off
③ Check whether the low voltage control power supply from the transformer to the ring main unit is normal
(2) Lighting inside the ring main unit switchgear
① Check whether the low voltage control power supply from the transformer to the ring main unit is normal
② Check whether the light bulb is damaged