Installation & Testing of Transformers & DG Set


  • During installation of Transformer on a Pole mounting structure, following checks should be made:
  • Ensure that the base channel of transformer is at height complying to IEC Standards:
    a) Height of top of HV bushing from ground for pole-mounted transformer should be 4.572 meters minimum (15 Ft)
    b) Height of top of HV bushing from ground for plinth mounted transformer should be 2.75 meters minimum (8 Ft)
  • Ensure that base channel is horizontally levelled
  • Avoid jerky movement of the transformer while lifting it upwards during installation.
  • During installation ensure that the HV bushings of the transformer are on the DO unit (or HG fuse unit) side of the structure.
  • After installation of transformer, also check that other allied Equipments such as AB switch, Horn Gap fuse units, DO Fuse sets, Lightening arrestor etc. are fitted at appropriate positions as per the applicable drawing issued by the utility.
  • DG SET

    Upon unpacking the generator from shipping cartons, first conduct a thorough inspection to detect any damage that may have occurred during shipment. Check whether the rated amperage / wattage capacity of the unit is adequate to handle all the intended loads during a power outage. If required, the critical loads may be grouped together and wired independently into an exclusive distribution panel. The unit should be placed outdoors in a protective enclosure, where sufficient air for cooling and ventilation is available in an unobstructed manner. The generator should be placed on a level surface, which is non-combustible and non-conducting, a little above ground level to prevent contact from rising water levels. The generator should be installed in close proximity to the location of the transfer switch and the fuel supply, to reduce the required length of cabling and piping respectively. You may be required to seek a permit if you intend to store a large fuel tank. The fuel pipe sizing, construction and layout must comply with NFPA 54 for natural gas applications and NFPA 58 for liquid propane applications. A grounding lug is usually provided for grounding the frame and external conducting parts of the equipment. It is essential to consult a qualified electrician to determine grounding requirements and follow procedures that meet local regulations. All batteries must be completely charged before they are inserted into the generator. Similar care must be ensured while unpacking and installing the transfer switch. The switch should be wall-mounted and all the points must be in level with each other to prevent distortion of the switch. The unit should be connected to the electrical system supplied by the utility only by means of the automatic transfer switch. This will ensure isolation between the generator’s electric system and the utility distribution system. Also, back-feed can occur wherein an improperly connected generator begins to feed electricity back into the power lines which will damage the unit and cause injury or death to the operating personnel. In the absence of a transfer switch, the safest option is to plug the essential appliances directly into the generator.