GB100048A - Improvements in or relating to Current Limiters or Electric Interrupters. - Google Patents

Abstract

100,048. Pettersen, K. Jan. 30, 1915, [Convention date]. Electro-magnetic interrupters. - A current limiter for simultaneously interrupting both parts of a two-rate supply when a pre-arranged maximum current supplied at two different tariffs (for example, for lighting and for heating) is exceeded comprises an electro-magnetic interrupter 8, 10 energized by a coil 7 the whole of which carries the high-tariff current for lighting and a part of which carries the low-tariff current for heating, so that the allowable low-tariff current is greater than the allowable high-tariff current, and when current for both purposes is used at the same time the effect of the heating current upon the interrupter is less than that of the lighting current. When the maximum demand from either or from a combination of both consumption circuits is excessive, the interrupter 8, 10 completes at 11, 12 the circuit of a second electro-magnetic switch 13 which breaks the supply circuit at 4 and the supply circuit is continuously made and broken until the demand is reduced. The coils carrying the two currents may be independent and of different sizes and connected in series or in parallel with one another. Thermal switches.-The actuating member of the interrupter may consist of thin and thick expansible wires 8, 9 carrying the low tariff and high tariff currants respectively and serving to hold a contact 11 out of engagement with a contact 12. A pre-arranged lighting current carried by the wire 8 alone or a higher heating current carried by the wire 9 alone or a combination of these having an equivalent expanding action will complete a circuit at 11, 12 and cause the supply to be intermittently interrupted as before. The wires may be duplicated and connected in parallel.