GB422827A - Improvements in and relating to electric transformers - Google Patents

Abstract

422,827. Transformers. BRITISH THOMSON - HOUSTON CO., Ltd., Crown House, Aldwych, London. May 24, 1934, No. 15533. Convention date, May 24, 1933. [Class 38 (ii)] A pot-type transformer has its primary winding contained in a shell, advantageously of metal and connected to a high potential, the shell being open at the top and embedded in a liquid or solid insulating material contained by the pot. A current transformer is shown having a two-part outer casing 11, 13 containing insulating material 12 in which is imbedded a casing 2, connected to the primary terminal 10, and supported by an insulating ring 15. The casing 2, if of metal, is slotted at 6 across its lower end and is lined as shown with heat insulating material 9, while it supports the primary winding 1. Inside and concentric with the primary winding are disposed respectively an insulating tube 8 and the secondary winding wound directly on the core 4 which passes through the shell 2 and the outer casing 13 and has its magnetic circuit completed by a yoke 5 passing round the casing 13. The tube 8 presses through the shell 2 and makes a tight joint with the casing 13 through packing material 14, so that the insulation 12 cannot enter the casing 2 The shell 2, if made of metal, acts as a cooling fin.