The outdoor switch-disconnector FLa 15/6400 andFLa 15/6410 (with fuse holders mounted below) havebeen developed for upright assembly.The switches comply with the regulations as per DINEN 62271-103 VDE 0671-103.The principle design and mounting dimensions correspond to the outdoor disconnecting switches 6400and 6410 as given in catalogue 751.The arc-extinguishing device which is shunted in theON position and is of the quick-make, quick-breaktype, has been adopted from the proven switch-disconnector FLa 15/60 (catalogue 762) which is usedas a line sectionalizer. All arching chambers are filledat the factory with approx. 0.5 litres of Shell Diala Dswitchgear oil.The main application for the switch-disconnectors FLa15/6400 and FLa 15/6410 is as feeder switch for polemounted transformer stations. The base frames arewelded from sectional steel and the operating shaftswhich are mounted in bronze bearings are hot-galvanized. All insulators used in the construction are madeof cycloaliphathic cast resin.All contacts with flat terminations in accordance withDIN 46206 and double contact blades are made ofelectrolytic copper are silver-plated and form looplesscurrent paths.The fuse holder contacts are designed to take HVHBC (high-voltage, high breaking capacity fuses)(catalogue 791) in accordance with DIN 43625.Adequate cross sections and suitable contact pressures mean that the switches still function easily andproperly after many years of operation.Outdoor operating mechanisms as described in ourcatalogue 776 are available for operating switch-disconnectors and earthing switches.