GB299346A - Improvements relating to electric regulating devices - Google Patents

Abstract

299,346. British Thomson-Houston Co., Ltd., and Parry, R. D. May 16, 1927. Regulation, automatic.-A regulator maintain. ing an electrical characteristic constant is associated with means for quickly readjusting the action of the regulator when the characteristic regulated varies to a predetermined extent above or below normal. An auxiliary relay may shortcircuit a coil of the regulator or a resistance in series therewith, vary the effect of retarding means such as a dashpot or take over the function of the main contact member during the abnormal conditions by operating on the circuit made by the regulator contacts. The auxiliary relay 25 shown in Fig. 1 short-circuits a resistance 30 in the circuit of the regulating coil 21 on low voltage and short-circuits the coil on excessive voltage. The dashpot 24 associated with the regulating coil 21, according to the modificcation shown in Fig. 2, has a sleeve 40 co-operating with V-shaped openings 43, and its retarding effect is suddenly reduced on high and low volts, to reduce the time lag of the regulator coil, by the auxiliary relay 25 and an electromagnet 36 adapted to move the sleeve. Fig. 3 shows an auxiliary relay 25 which operates upon normally open contacts 31<1> and normally closed contacts 321 to short-circuit the resistance 11 controlled by the regulator contacts upon low volts and to open the circuit through the regulator contacts on high volts, thus taking over the regulator function. The torque-type regulator shown in Fig. 4 is associated with a series resistance 30, which is short-circuited by the relay 25 on high volts, the regulator coils being short-circuited on low volts. A relay operating on the resistance controlled by a torque-type regulator is also described.