On Load Tap Changer (OLTC)
    On Load Tap Changers and Oil Cable Boxes Explosion and Fire Prevention

     In addition to the tank, SERGI strongly recommends to protect the On Load Tap Changers and the Oil  Cable
     Boxes  with the TRANSFORMER PROTECTOR. For that purpose, a Depressurisation Set and a specific Explosive
     Gas Elimination Set are used.

    Protecting all transformer oil capacities prevents the short-circuit from damaging the On Load Tap Changer or the Oil
    Cable Box, and spreading the fire to the transformer itself as well as to the whole power plant or substation. For a
    Minor additional price, the TP offers a complete explosion and fire prevention system for the transformer.



* Please click on picture ( For view the enlarged image ).

    On Load Tap Changer (OLTC)
    Examples exist where as little as 200 litres (50 gallons) of burning oil from the OLTC have destroyed
    a complete substation.

    When not connected to the TRANSFORMER PROTECTOR, OLTCs are protected against overpressure with a diaphragm or a
    Pressure Relief Valve, which are not calibrated and do not allow oil channelling during an explosion.

    In fact, during short-circuits, the OLTC cover is always forced off and burning oil then spreads onto the transformer, floor and
    surrounding equipment, leading to a fire expansion to the whole plant. 

    SERGI’s long collaboration with major OLTC manufacturers has resulted in the protection of every type of OLTC. This is why  
    SERGI strongly recommends to protect all of them, using a flange for depressurisation and a pipe that goes to the bottom of
    the OLTC to eliminate explosive gases.