Compact Substation to Greater Tehran Electricity Distribution Standards

A walk-in prefabricated compact substation built to the standards and requirements of the Greater Tehran Electricity Distribution Company. It has three medium-voltage cells arranged as SPC+SPC=SPC (SPC: fused switch-disconnector); when the fused disconnector opens, the output feeds the 630 kVA power transformer via an on/off lever, and a striker-pin mechanism trips the disconnector if any fuse blows. Medium-voltage connections use cross-linked (XLPE) cable, while the low-voltage side uses busbar connections for adequate current capacity. On the low-voltage side, a lighting fuse panel feeds street lighting, plus six outputs each with a 400 A vertical fuse switch, all fed from a 1600 A three-pole automatic incoming breaker. With this arrangement it has become one of the standard assets used by the Greater Tehran distribution company to meet subscriber demand.