Patent
Solid state relay with zero crossover feature
TLDR
In this article, a photo transistor and SCR are coupled in parallel between the d.c. terminals of a full wave rectifier and the collector of a transistor that is connected in an common emitter configuration.Abstract:
A solid state relay in which the control circuit for controlling a bidirectional conduction device (triac) includes a silicon controlled rectifier (SCR) and a photo transistor that is responsive to a light coupled control signal. Both the SCR and the photo transistor are coupled in parallel between the d.c. terminals of a full wave rectifier. The base of the photo transistor and the gate of the SCR are coupled to the collector of a transistor that is connected in an common emitter configuration between the d.c. terminals of the rectifier. The last-named transistor has its base connected to the collector of the photo transistor. The last-named transistor is a zero voltage crossover detector and conducts only when the photo transistor is nonconducting. The photo transistor and SCR may conduct only when the crossover detector transistor is nonconducting.read more
Citations
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Patent
High Power DC Blocking Device for AC and Fault Current Grounding
Brian R. Pelly,Henry N. Tachick +1 more
TL;DR: In this paper, a high power DC blocking device is provided which blocks DC current, passes AC current, and limits the voltage across it under fault conditions, while allowing the passage of normal AC currents.
Patent
Power supply and control circuit for series connected controller
TL;DR: In this article, a control circuit for a triac to be connected in series with a load device, at a situs where only one AC power conductor and a conductor extending to the load device is available, is described.
Patent
Solid state hybrid switch
TL;DR: In this article, the authors proposed a hybrid switch having a solid state circuit (2a) including a thyristor (SCR) for closing and reopening a supply circuit (S,4,6) to a load (L) and contacts including an isolating contact (S1) for connecting power to and disconnecting power from the solid-state circuit (1a), a control contact(S2) for initiating turn-on and turn-off of the SCR, and a bypass contact (s3) for shunting the solidstate circuit after the
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Isolator surge protector for dc isolation and ac grounding of cathodically protected systems
Brian R. Pelly,Henry N. Tachick +1 more
TL;DR: An isolator surge protector for use with corrosion protection systems which are an inherent part of or coupled to an electrical power system, for power transformers, and for DC transmission systems, where it is necessary to present a high impedance to DC and a low impedance to AC up to a predetermined voltage level as mentioned in this paper.
Patent
Device and method for triggering a gas furnace ignitor
TL;DR: In this paper, an ignitor controller was proposed to reduce EMI levels caused by the constant triggering of AC line voltage to the ignitor switch after +/−five volts, which constant triggering is needed to properly operate ignitors in electronic ignition systems.
References
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Patent
Protective arrangement for dependent switching circuits
TL;DR: In this paper, a fusible resistor in a solid astate relay comprising two solid state switches con-nected in parallel with each other, but in series with a load and a source of current was proposed.
Patent
Electronic switching circuit with zero voltage switching
Richard W. Fox,Jerome R Mullaly +1 more
TL;DR: In this article, an electronic switch circuit including a switching thyristor with two switch terminals that are connected to a controlled circuit is described, where a trigger circuit is coupled to the gate terminal to selectively supply trigger signals and the trigger circuit receives its power from a power supply which is connected to switch terminals and draws its energy from the controlled circuit.