Arrangement for sensing remote binary inputs

• US 4,574,355 A
• Filed: 11/02/1983
• Issued: 03/04/1986
• Est. Priority Date: 11/02/1983
• Status: Expired due to Term

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Miller, Edward B., Huber, Paul G., Beatty, Robert M.
• Primary Examiner(s): Wise, Edward J.
• Application Number:
  US06/548,110
• Time in Patent Office: 853 Days
• Field of Search: 364/492, 364/493, 364/483, 307/38, 307/113, 307/40, 307/115, 307/140, 307/131, 307/39, 375/107, 340/310 A, 340/825.06, 340/825.07
• US Class Current: 700/295
• CPC Class Codes: H02J 13/00002 characterised by monitoring
• CPC Class Codes: H02J 13/00016 using a wired telecommunication network or a data transmission bus
• CPC Class Codes: H02J 13/00036 the elements or equipment being or involving switches, relays or circuit breakers circuits for indication of single switches H01H9/167
• CPC Class Codes: Y02E 60/00 Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
• CPC Class Codes: Y04S 10/18 using switches, relays or circuit breakers, e.g. intelligent electronic devices [IED]
• CPC Class Codes: Y04S 10/30 State monitoring, e.g. fault, temperature monitoring, insulator monitoring, corona discharge
• CPC Class Codes: Y04S 40/124 using wired telecommunication networks or data transmission busses

Abstract

An improved switch input arrangement for a system that remotely controls distributed electrical loads. The switch input arrangement is part of a transceiver decoder that receives commands from central controller for controlling the state of latching relays for controlling the power circuits of the loads. The improvements include: monitoring the state of contact closure inputs to the transceiver decoder, selectively enabling/disabling specific contact closures to control the masking of switch inputs, inclusion of an accumulated switch buffer to store the last actuation state of all relays, an answerback to insure that action occurs responsive to a switch input, a shifting threshold and multiplexing technique for more accurate reading of contact closure switch inputs, and the inclusion of a power-up reset message annunciated to the central controller to alert it that certain commands may have to be issued in order to reestablish the desired states of the transceiver.

Claims

1. In a system for controlling distributed electrical loads including a central controller for providing a data signal defining the manner in which said loads are to be controlled;

plural transceiver devices, each device being connected to control a subset of said loads by controlling relays in respective power circuits of said loads and including means for receiving contact closure inputs and transmitting information related thereto to the central controller; and

a single data line connecting said central controller with each transceiver device, and improved transceiver device, comprising;

means, coupled to said receiving means, for monitoring the current state of any contact closure input to said transceiver and transmitting information indicative thereof to the central controller.

2. In a system for controlling distributed electrical loads including a central controller for providing a data signal defining the manner in which said loads are to be controller;

plural transceiver devices, each device being connected to control a subset of said loads by controlling relays in respective power circuits of said loads and including means receiving contact closure inputs and transmitting information related thereto to the central controller; and

a single data line connecting said central controller with each transceiver device, and improved transceiver device, comprising;

means for selectively disabling a contact closure input such that a contact closure on the disabled input will not cause data indicative of that contact closure input to be transmitted to the central controller, thereby providing a masking override function for such an input.

3. In a system for controlling distributed electrical loads including a central controller for providing a data signal defining the manner in which said loads are to be controlled;

plural transceiver devices, each device being connected to control a subset of said loads by controlling relays in respective power circuits of said loads and including means for receiving contact closure inputs and transmitting information related thereto to the central controller; and

a single data line connecting said central controller with each transceiver device, and improved transceiver device, comprising;

means, coupled to said receiving means for accumulating contact closure inputs and maintaining a record of the last received contact closure for each contact closure input of said transceiver; and

means for interrogating said accumulating means as to the last contact closure state of any switch input and transmitting data indicative thereof to said central controller.

4. A system for controlling distributed electrical loads comprising:

a central controller for providing a data signal defining the manner in which said loads are to be controlled;

plural transceiver devices, each device being connected to control a subset of said loads by controlling relays in respective power circuits of said loads and including means for receiving contact closure inputs and transmitting information related thereto to the central controller;

and a single data line connecting said central controller with each transceiver device;

means for providing from said central controller to said transceiver decoder an acknowledgement of received information indicative of a contact closure input to said transceiver decoder.

5. A system according to claim 4 further comprising means at said transceiver for periodically retransmitting information related to contact closures until receiving a positive acknowledgement of the information from the central controller.

6. In a system for controlling distributed electrical loads including a cental controller for providing a data signal defining the manner in which said loads are to be controlled;

plural transceiver devices, each device being connected to control a subset of said loads by controlling relays in respective power circuits of said loads and including means for receiving contact closure inputs and transmitting information related thereto to the central controller; and

a single data line connecting said central controller with each transceiver device, and improved transceiver device, comprising;

means for providing a changeable threshold reference providing first and second threshold signals;

means for comparing a contact closure input with said first threshold signal; and

means, in the event of a favorable comparison with said first threshold in accordance with predetermined criteria, for further comparing the contact closure input with said second threshold signal to determine whether a contact closure actually occurred.

7. An improved transceiver device according to claim 6 further comprising means for multiplexing contact closure inputs onto a number of lines less than the total number of contact closure inputs associated with the transceiver for coupling to a processor of said transceiver.

8. In a system for controlling distributed electrical loads including a central controller for providing a data signal defining the manner in which said loads are to be controlled;

plural microprocessor-based transceiver devices, each device being connected to control a subset of said loads by controlling relays in respective power circutis of said loads and including means for receiving contact closure inputs and tarnsmitting information related thereto to the central controller; and

a single data line connecting said central controller with each transceiver device, and improved transceiver device, comprising;

a watchdog reset circuit coupled to said microprocessor for monitoring the operation thereof, and providing a reset signal thereto in the event of a failure of proper operation thereof, said watchdog reset circuit being AC coupled to said microprocessor so that its operation is not defeated by a malfunction that would cause a DC condition in a signal resetting a watchdog timer of the watchdog reset circuit; and

means, responsive to a reset of said microprocessor for annunciating a reset message, via said data line, to said central controller.

9. An improved transceiver device according to claim 8 further comprising means, coupled to said watchdog reset circuit, for preventing erroneous switch transmissions from said transceiver to said central controller on power-up thereby preventing regeneration of a previously processed contact closure.