This guide deals with the distribution transformer construction (core, windings, cooling, tank & cover, conservator, pressure relief device, Buchholz relay, silica gel breather, winding temperature indicator, etc. ), transport & packing & despatch, installation procedure, fittings & accessories. Installation Select an appropriate location: It is usually installed inside the distribution box, close to the power inlet side, in a place that is convenient for installation and maintenance. At the same time, ensure there is sufficient safety distance between the current transformer and other. - For surface-mounted distribution boxes on the wall, the indoor ceiling, wall, and decoration should be completed before installation; for flush-mounted control (distribution) boxes, the reserved holes, and conduits for power and lighting wiring should be inspected and qualified. - Before. ufacturer's guidelines. It is recommended that the transformer should be thoroughly inspected every 12 months, and attention given to maintenance of all items where neces l oil) should be avoided. For further information regarding transformer oil handling, please refer to relevant ma uk gnated. primary unit substation is a close-coupled assembly consisting of enclosed primary high-voltage equipment, three-phase power transformer and enclosed secondary medium-voltage equipment.