Power control apparatus

• US 5,019,956 A
• Filed: 11/14/1989
• Issued: 05/28/1991
• Est. Priority Date: 11/16/1988
• Status: Expired due to Term

• Current Assignee: Terasaki Denki Sangyo
• Original Assignee: Morii Dengyo Kabushi Kaisha, Ohbayashi Corp., Terasaki Denki Sangyo
• Inventors: Kamino, Toshihide, Morii, Toshimichi, Nakayama, Katsutoyo
• Primary Examiner(s): Wong, Peter S.
• Application Number:
  US07/436,211
• Time in Patent Office: 560 Days
• Field of Search: 363/50, 361/62, 361/63, 361/87, 361/93, 361/96, 361/99, 340/664, 340/650, 340/651
• US Class Current: 363/50
• CPC Class Codes: H01H 2071/006 Provisions for user interfaces for electrical protection devices
• CPC Class Codes: H01H 2300/03 Application domotique, e.g. for house automation, bus connected switches, sensors, loads or intelligent wiring
• CPC Class Codes: H01H 89/06 Combination of a manual reset circuit with a contactor, i.e. the same circuit controlled by both a protective and a remote control device
• CPC Class Codes: H02H 3/00 Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems H02H7/00; systems for change-over to standby supply H02J9/00 ; integrated protection for motors H02H7/0822
• CPC Class Codes: H02H 3/006 Calibration or setting of parameters
• CPC Class Codes: Y02B 70/30 Systems integrating technologies related to power network operation and communication or information technologies for improving the carbon footprint of the management of residential or tertiary loads, i.e. smart grids as climate change mitigation technology in the buildings sector, including also the last stages of power distribution and the control, monitoring or operating management systems at local level
• CPC Class Codes: Y02B 90/20 Smart grids as enabling technology in buildings sector smart grids supporting the management or operation of end-user stationary applications in general, or like technologies with no associated climate change mitigation effect Y04S20/00
• CPC Class Codes: Y04S 20/14 Protecting elements, switches, relays or circuit breakers
• CPC Class Codes: Y04S 20/20 End-user application control systems

Abstract

In this power control apparatus, a current flowing in a main current (201) is detected by a current transformer (202) and a zero-phase current transformer (203), provided in the main circuit. A value of this current is provided to a CPU (214) included in an intelligent controller (207). A maximum peak value and the like are evaluated by the CPU to be compared with predetermined set values. If those values are equal to or higher than the set values, an excitation signal is applied to a tripping device (205) to release a latch by a latch scheme (206) and thus to trip the circuit breaker. The CPU alters the set value when supplied with a setting alteration instruction from a central monitor (40), and causes the circuit breaker to be tripped when supplied with a stop instruction therefrom.

Claims

1. A power control apparatus for controlling the supply of plural phase electrical power to a main circuit, comprising:

circuit breaking means having contacts connected in said main circuit and selectively operable to close said contacts for supplying said electrical power to said main circuit and to open said contacts and thereby break the supply of electrical power to said main circuit, and to switch said contacts between open and closed conditions;

means for detecting the present level of current flowing in said main circuit and providing a corresponding, current level detection output;

setting means for setting a predetermined current level value and predetermined conditions relating to breaking of the main circuit when the present current level exceeds the predetermined current level set value;

means for supplying switching instructions for switching of said circuit breaking means;

control means responsive to said switching instructions for controlling said circuit breaking means to switch between said open and closed conditions of said contacts and further responsive to the set values of said setting means and the current level detection output of said detecting means for generating a current level monitor signal and, in response to the current level in said main circuit exceeding said predetermined current level set value, for generating an output signal in accordance with said predetermined conditions;

tripping means, responsive to the output signal of said control means, for operating said circuit breaking means to break the main circuit; and

display means for receiving and displaying the predetermined current level set value from the setting means and for receiving the current level monitor signal output of said control means and displaying the corresponding present main circuit current value.

2. A power control apparatus as recited in claim 1, wherein said switching instruction supplying means comprises communication means for receiving switching instructions from source means, external of said apparatus, for supply to said control means, said control means responding to said externally supplied switching instructions for controlling the operation of said circuit breaking means for switching said contacts thereof between said open and closed conditions.

3. A power control apparatus as recited in claim 1, wherein said circuit breaking means comprises:

mechanical latch means having reset and released conditions and operable in said reset condition to permit said circuit breaking means to switch the contacts thereof to said closed condition; and

said mechanical latch means being operated by said tripping means to said released condition for, in turn, operating said circuit breaking means to break the main circuit.

4. A power control apparatus as recited in claim 3, further comprising means for resetting said latch means.

5. A power control apparatus as recited in claim 4 wherein said resetting means comprises manual resetting means.

6. A power control apparatus as recited in claim 4 wherein said resetting means is responsive to and operated by an output of said control means.

7. A power control apparatus as recited in claim 6 wherein said circuit breaking means is operable in response to an output signal of said control means, in the reset condition of said latch means, for switching said contacts thereof to said closed condition.