Switch Fuse Combination Transformer Protection Cubicle Changing Procedure of Tripped Fuse

  • When any of the fuses are tripped, in order not to leave the transformer with 2 energized phases,Load Break Switch will automatically open itself and cut the energy from all 3 phases to protect the transformer.
  • Considering there might be a generator in the network, Check the cubicle is not energized by observing the VPI ( Voltage Presence Indicator ) device.
  • Close the earthing switch.
  • Check the earthing switch’s position is closed from the mimic diagram and control window.

  • Open the cable connector compartment’s cover.
  • Fuse manufacturers are highly recommending to change all the fuses in the cubicle, even thoughonly one fuse has been tripped !!! Select the fuse amperages according to the fuse selection chart upon the cubicle. Firstly place the fuses’ bottom contact and then secondly place the fuses’ top
    contact by making sure that the fuses’ tripping pins to be on top and lastly close the locking latch.
  • Close the cable connector compartment’s cover.
  • Make sure that the auxilliary supply of the cubicle is energized.
  • Check the load break switch’s gas pressure level is in normal state from both manometer and indicator lamps.
  • Open the earthing switch.
  • Check the earthing switch’s position is open from the mimic diagram and control window.
  • Charge the load break switch’s closing spring. If the cubicle is motorized, the spring will be automatically charged.
  • Close the load break switch whether from the mechanical button over the mechanism or from the remote control cable with electrical buttons.
  • Check if the cubicle’s outgoing is energized by observing the VPI ( Voltage Presence Indicator )device.