HXGN¡õ40.5 SF6 RMU (hereafter referred to as Ring Main Unit))is 50 HZ Indoor three-phase AC HV Switchgear. Load switch, earthing switch and the busbar of its circuit are fitted in the metal enclosure. Besides, it is a composite apparatus adopting spring operating mechanism and SF6 gas as arc extinction medium and insulation medium. It is suitable for 40.5 kV ring main power supply or two-radiation power supply. It changes the original single radiation power supply. When power supply line fails, it can restore the circuit of transformer and enhances the reliability and use actor of power supply largely. It is specialized in trading estate or villages and towns where electricity power is largely needed. It is safety in use, easily installed, less maintenance, less in space and not influenced by the climate. It is suitable for being fitted in the combined substation. And the load switch or load switch-fuse composite apparatus inside the RMU is able to be used separately.

Product feature :
      a. It consists of switch compartment, fuse compartment, operating mechanism compartment and cable compartment(bottom frame).
      b. The switch compartment consists of function circuit (including earthing switch and load switch) and busbar among the circuits. The metal enclosure is welded 3mm cold rolled steel sheet (or corrosion resistance plate). Each function circuit includes a load switch and earthing switch. The load switch is made up of moving contact which runs vertically and the static contact at the bottom. When the switch closes, the moving contact moves down and the load switch opens. The earthing switch is made up of moving contact and static contact. When the spring runs, the earthing switch is cut in immediately. There are four rectangle pilot holes on the upper parts of the switch department and at the back of the switch. There is a inspection window on the right side of the RMU, through which"O" and "C" position of the earthing switch can be seen. Hydrostat is mounted at the back of the RMU.
       c. The load switch adopts air blast structure, which enhances the arc extinction capacity, but won't  affect the insulation of phase to phase and phase to earth. Besides both of moving contact and static contact have arc contacts, which increase the breaking times.
      d. Both of fuse switch and load switch compartment consist of the protection circuit of transformer. The HV current limiting fuse is fitted in the epoxy casting insulating closure. When the fuse melts, then firing pin will bounces out, next the load switch opens.
      e. Operating mechanism compartment is on the right side of the RMU. In each function circuit, the load switch has a manual drive ( or motor drive ) power spring operating mechanism and the earthing switch has a manual drive power spring operating mechanism. There are a closing and manual drive breaking screwing button of load switch, the on/off operating hole of earthing switch, on/off indicator light and motor drive on/off button of load switch, simulated line, condition display plate of switch, lock position on the faceplate. Both of the load switch and the earthing switch own interlock devices to prevent from incorrect manipulation.

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Ordering notice :
      Please provide the followings while ordering ;
      a. The product name, pattern, size, quantity, rated voltage of fuse and delivery time ;
      b. Pareto diagram and layout plan of UMU ;
      c. Spare part needed (such as gas-filling device and deflation device) ;
      d. Cubical colour ;
      e. If any special request, please negotiate with us