Energy information device and graphical display for a circuit breaker

• US 6,292,717 B1
• Filed: 03/19/1998
• Issued: 09/18/2001
• Est. Priority Date: 03/19/1998
• Status: Expired due to Term

• Current Assignee: Siemens Industry Incorporated (Siemens AG)
• Original Assignee: Siemens Energy & Automation Incorporated (Siemens AG)
• Inventors: King, William A., Alexander, James O., Leone, David A.
• Primary Examiner(s): Gordon, Paul P.
• Application Number:
  US09/044,716
• Time in Patent Office: 1,279 Days
• Field of Search: 700/286, 700/292, 700/293, 700/291, 700/21, 700/22, 700/9, 700/17, 700/83, 702/57, 702/58, 702/64, 702/188, 361/62, 361/63, 361/64, 340/286.01, 340/825.06, 340/825.16, 340/825.36, 340/501, 340/506
• US Class Current: 700/293
• CPC Class Codes: G01R 19/2513 Arrangements for monitoring electric power systems, e.g. power lines or loads; Logging
• CPC Class Codes: G01R 22/00 Arrangements for measuring time integral of electric power or current, e.g. electricity meters
• CPC Class Codes: H01H 2071/006 Provisions for user interfaces for electrical protection devices
• CPC Class Codes: H02H 1/0053 Means for storing the measured quantities during a predetermined time
• CPC Class Codes: H02H 3/006 Calibration or setting of parameters
• CPC Class Codes: H02H 3/04 with warning or supervision in addition to disconnection, e.g. for indicating that protective apparatus has functioned watching of pilot wires H02H1/0084; protection of protective arrangements H02H7/008; indication of the state of electronic switches H03K17/18

Abstract

An energy information system for use with a circuit breaker coupled between a power source and a load, the energy information system comprising: sensing apparatus for sensing at least one of i) a voltage, and ii) a current flowing between the power source and the load through the circuit breaker; detecting apparatus for detecting transitions of a sensed voltage; counting apparatus for counting a number of times the circuit breaker trips and interrupts the current flow between the power source and the load; measuring apparatus for i) measuring the current flow through the circuit breaker when the circuit breaker trips and interrupts the current flow between the power source and the load and ii) determining a plurality of energy related parameters including a measure of at least one of the voltage, the current and the frequency based on an output from the detecting apparatus, between the power source and the load; input apparatus for accepting a user input, the user input controlling at least one of the circuit breaker and a display apparatus; the display apparatus for displaying at least one of the plurality of conditions of the circuit breaker responsive to the input apparatus; and communication apparatus coupled to the input apparatus for selectively communicating at least one of the plurality of energy related parameters to a remote terminal.

Claims

1. An energy information system for use with a circuit breaker coupled between a power source and a load, the energy information system comprising:

sensing means for sensing at least one of i) a voltage, and ii) a current flowing between the power source and the load through the circuit breaker;

detecting means for detecting transitions of a sensed voltage;

counting means for counting a number of times the circuit breaker trips and interrupts the current flow between the power source and the load;

measuring means for i) measuring the current flow through the circuit breaker when the circuit breaker trips and interrupts the current flow between the power source and the load and ii) determining a plurality of energy related parameters including a measure of at least one of the voltage, the current and the frequency based on an output from the detecting means, between the power source and the load;

input means for accepting a user input, the user input controlling at least one of the circuit breaker and a display means;

the display means for displaying at least one of the plurality of conditions of the circuit breaker responsive to the input means; and

communication means coupled to the input means for selectively communicating at least one of the plurality of energy related parameters to a remote terminal.

2. The energy information system of claim 1, wherein the counting means includes:

a mechanical counter means for determining a first count value based on a total number of times the circuit breaker trips;

an interruption level counter means for determining a second count value, the second count value indicating a current range flowing between the power source and the load when the circuit breaker trips; and

a fault counter means for determining a third count value, the third count values indicating a count of a fault condition that trips the circuit breaker.

3. The energy information system of claim 1, further comprising security means for selectively allowing access to control the energy information system.

4. The energy information system of claim 3, wherein said security means is a password entered using said input means.

5. The energy information system of claim 4, wherein the biasing means further comprises:

a generating means for generating a stable reference voltage; and

a buffer means coupled to the generator for buffering the stable reference voltage and generating the predetermined biased value.

6. The energy information system of claim 1, wherein the sensing means further comprises:

converting means for converting the voltage of the power source to a lower voltage;

biasing means for biasing the lower voltage above a ground potential by a predetermined bias value to produce a full-wave biased voltage,

wherein the measuring means processes the full-wave biased voltage to determine the plurality of conditions of the circuit breaker.

7. The energy information system of claim 1, wherein the sensing means has a voltage input range from about 50% to 125% of the voltage of the power source.

8. The energy information system of claim 1, wherein the display means displays the plurality of conditions in one of a plurality of languages based on a user selection.

9. The energy information system of claim 4, further comprising memory means f or storing a date of manufacture of the circuit breaker.

10. The energy information system of claim 9, wherein the date-of manufacture is at least one of i) displayed on the display means and ii) sent to the remote terminal by the communication means.

11. The energy information system of claim 10, wherein the demand is determined by calculating according to the following equation:

$\frac{\underset{n=1}{\overset{T_{\mathrm{PRG}}}{\sum <br><br>}}<br><br>\left(\frac{I_A+I_B+I_C}{3}\right)}{T_{\mathrm{PRG}}}=\mathrm{AmpDemand}$

where

T_PRG is a programmable demand period, and

I_A, I_B and I_C are phase currents for phases A, B and C, respectively.

12. The energy information system of claim 1, wherein the plurality of energy related parameters includes at least one of i) an energy demand based on at least one of the current and the voltage sensed by the sensing means over a predetermined period of time and ii) a plurality of RMS parameters measured over a range of harmonics of a fundamental frequency of the power source.

13. The energy information system of claim 12, wherein the predetermined period of time is between about 1 and 90 minutes, the period of time selectable by the user through at least one of the input means and the communications means.

14. The energy information system of claim 1, wherein the energy information system is adaptable for mounting within the circuit breaker.

15. The energy information system of claim 14, wherein the energy information system is field installable within the circuit breaker.

16. An energy information system for use with a circuit breaker coupled be en a power source and a load, the energy information system comprising:

a sensor to sense at least one of i) a voltage and ii) a current flowing between the power source and the load through the circuit breaker;

a transition detector to detect transitions of a sensed voltage from the sensor;

a counter coupled to the sensor to count a number of times the circuit breaker trips and interrupts the current flow between the power source and the load;

a energy information controller coupled to the sensor and counter to measure the current flow through the circuit breaker when the circuit breaker trips and interrupts the current flow between the power source and the load and for measuring a plurality of related parameters, including a measure of at least one of the voltage, the current and the frequency based on an output from the transition detector;

an input device coupled to the energy information controller to enter a user input for controlling at least one of the circuit breaker and a display;

the display coupled to the energy information controller to display at least one of the plurality of power related parameters responsive to the user input; and

a communication port coupled to the energy information controller to selectively communicate at least one of the plurality of power related parameters to a remote terminal.

17. The energy information system of claim 16, wherein the counter further includes:

a mechanical counter to determine a first count value based on a total number of times the circuit breaker trips;

an interruption level counter to determine a second count value, the second count value indicating a current range flowing between the power source and the load when the circuit breaker trips; and

a fault counter to determine a third count value, the third count value indicating a count of a fault condition indicative of a circuit breaker trip.

18. The energy information system of claim 17, wherein the second count value is a plurality of count values of respective ranges of current flows, the ranges of current flows selected from the group consisting of

i) the current flow being less about than 100% of a trip rating of the circuit breaker;

ii) the current flow being between about 100% and 300% of the trip rating of the circuit breaker;

iii) the current flow being between about 300% and 600% of the trip rating of the circuit breaker,

iv) the current flow being between about 600% and 900% of the trip rating of the circuit breaker; and

v) the current flow being greater than about 900% of the trip rating of the circuit breaker.

19. The energy information system of claim 17, wherein the third count value includes at least one of the group consisting of:

i) an overload fault count value;

ii) a short time fault count value;

iii) an instantaneous fault count value; and

iv) a ground fault count value.

20. The energy information system of claim 17, wherein the energy information system is field installable within the circuit breaker.

21. The energy information system of claim 16, wherein the sensor comprises:

a voltage transformer to convert a line voltage of the power source to a voltage lower than the line voltage; and

a voltage shifter to bias the lower voltage above a ground potential by a predetermined voltage to produce a full-wave biased voltage signal,

wherein the energy information controller measures the full-wave biased voltage signal to determine the plurality of energy related parameters.

22. The energy information system of claim 16, wherein the transition detector has a voltage input range from about 50% to 125% of the voltage of the power source.

23. The energy information system of claim 16, wherein the communication port comprises at least one of an RS-232 communication port and an RS485 communication port, each of the communication ports providing for upload and download of data between the remote terminal and the energy information controller.

24. The energy information system of claim 16, wherein the display displays the plurality of energy related parameters in one of a plurality of languages based on a user selection, the selection made through at least one of the input device and the communication port.

25. The energy information system of claim 16, further comprising a memory for storing a date of manufacture of the circuit breaker.

26. The energy information system of claim 25, wherein the date of manufacture is at least one of displayed on the display and sent to the remote terminal through the communication port.

27. The energy information system of claim 16, wherein the plurality of energy related parameters includes at least one of i) an energy demand based on at least one of the current and the voltage sensed by the sensor over a predetermined period of time and, ii) a plurality of RMS parameters measured over a range of harmonics of a fundamental frequency of the power source.

28. The energy information system of claim 27, wherein the range of harmonics includes up to at least about a 19th harmonic of the fundamental frequency.

29. The energy information system of claim 27, wherein the predetermined period of time is between about 1 and 90 minutes, the period of time selectable by the user through at least one of the input device and the communication port.

30. The energy information system of claim 27, wherein the demand is determined by calculating according to the following equation:

$\frac{\underset{n=1}{\overset{T_{\mathrm{PRG}}}{\sum <br><br>}}<br><br>\left(\frac{I_A+I_B+I_C}{3}\right)}{T_{\mathrm{PRG}}}=\mathrm{AmpDemand}$

where

T_PRG is a programmable demand period, and

I_A, I_B and I_C are phase currents for phases A, B and C, respectively.

31. The energy information system of claim 30, wherein the demand calculation is performed automatically about once a second.

32. The energy information system of claim 16, wherein the energy information system is adaptable for mounting within the circuit breaker.

33. The energy information system of claim 16, further comprising a security controller to selectively allow access to the energy information system by the input device.

34. An energy information system for use with a circuit breaker coupled between a power source and a load, the energy information system comprising:

a sensor to sense at least one of i) a voltage and ii) a current flowing between the power source and the load through the circuit breaker;

a transition detector to detect transitions of a sensed voltage from the sensor;

a voltage shifter coupled to the sensor to bias the voltage above a ground potential by a predetermined voltage to produce a full-wave biased voltage waveform;

a counter to determine

i) a first count value based on a total number of times the circuit breaker trips;

ii) a second count value indicating a current range flowing between the power source and the load when the circuit breaker trips, the current range based on percentage of a trip rating of the circuit breaker; and

iii) a third count value indicating a count based on a predetermined fault condition of the circuit breaker;

an energy information controller coupled to the sensor, the counter, the transition detector and the voltage shifter, the energy information controller measuring i) the current flow through the circuit breaker when the circuit breaker trips and ii) the full-wave biased voltage waveform to determine the plurality of energy related parameters of the circuit breaker;

an input device coupled to the energy information controller to enter a user input for controlling at least one of the circuit breaker and a display;

a memory to store a date of manufacture of the circuit breaker;

the display coupled to the energy information controller to display at least one of i) the plurality of conditions and ii) the date of manufacture of the circuit breaker responsive to the user input, the plurality of energy related parameters including

a) an energy demand; and

b) a plurality of RMS parameters measured over a range of harmonics of a fundamental frequency of the power source based on at least one of the voltage, the current and the frequency over a predetermined period of time,

a security controller to selectively allow access of the energy information system by the input device; and

a communications port including at least one serial communications port, the communications port coupled to the energy information controller to selectively communicate with a remote terminal;

wherein the communication port provides for upload and download of data between the remote terminal and the energy information controller.

35. An energy information device for use with a circuit breaker having a trip unit, the energy information device coupled between a power source and a load, the device comprising:

a plurality of current sensors having an input coupled to respective ones of a plurality of power lines between the power source and the load;

a plurality of transformers coupled between the respective ones of the plurality of power lines and an analog to digital converter (ADC);

a transition detector having an input coupled to an output of one of the plurality of transformers;

an override circuit coupled to an output of the plurality of current sensors, an input of a power supply and a first microprocessor;

a trip circuit having a first input coupled to an output of the override circuit;

the first microprocessor further coupled to a first programmable read only memory (PROM), a second input of the trip circuit, and a second microprocessor; and

the second microprocessor further coupled to an output of the transition detector, an output of the ADC, a clock circuit, a second PROM and a random access memory (RAM).

36. The energy information device of claim 35, further comprising:

a first digital input/output (I/O) interface coupled to the first microprocessor; and

a second digital I/O interface coupled to the second microprocessor.

37. The energy information device of claim 35, further comprising a liquid crystal display (LCD) coupled to the second microprocessor.

38. The energy information device of claim 35, further comprising a test connector coupled to the second microprocessor.

39. The energy information device of claim 35, further comprising a rating plug coupled to the first microprocessor.

40. The energy information device of claim 35, further comprising:

a first signal conditioner coupled between the plurality of current sensors and the first microprocessor, and

a second signal conditioner coupled between i) the plurality of current sensors and the plurality of transformers and ii) the ADC.

41. The energy information device of claim 35, wherein the transition detector comprises:

a filter having an input coupled to the output of one transformer to filter an AC signal from the transformer;

a comparator coupled to the filter to compare a filtered output of the filter to a voltage;

an amplifier for amplifying an output of the comparator; and

,

an inverter for inverting an output of the amplifier and producing a signal representative of an AC signal frequency,

wherein transition information is supplied to the second microprocessor based on the AC signal frequency.

42. An energy information device for use with a circuit breaker having a trip unit, the energy information device coupled between a power source and a load, the device comprising:

a signal conditioner coupled to a plurality of power lines between the power source and the load providing conditioned signals based on an input signal representative of a current flowing between the power source and the load;

an override circuit coupled to an output of the signal conditioner;

a filter coupled to a first output of the override circuit to filter the first output of the override circuit;

a microprocessor coupled to an output of the filter;

a memory coupled to the microprocessor; and

a trip circuit coupled to an output of the microprocessor and a further output of the override circuit, and generating a trip signal for the trip unit based on at least one of i) the further output of the override circuit and ii) the output of the microprocessor.

43. The energy information device of claim 42, further comprising a rating plug coupled to the microprocessor.

44. The energy information device of claim 42, wherein the input signal is a differential input signal and the override circuit converts the differential input signal into a single ended output signal.

45. An energy information device for use with a circuit breaker having a trip unit, the energy information device coupled between a power source and a load, the device comprising:

a first amplifier coupled to a plurality of power lines between the power source and the load, providing first amplified signals based on a first input signal representative of a plurality of currents flowing between the power source and the load;

a second amplifier coupled to the plurality of power lines between the power source and the load, providing second amplified signals based on a second input signal representative of a respective plurality of voltages provided by the power source to the load;

a transition detector coupled to an output of the second amplifier to detect a transition of a voltage signal based on one of the plurality of voltages, and generating a transition signal used in determining a frequency of the voltage signal;

a first analog-to-digital converter (ADC) coupled to an output of the first amplifier to generate a first digital output signal representative of the plurality of currents based on an offset value;

a second ADC coupled to an output of the second amplifier to generate a second digital output signal representative of the plurality of voltages based on the offset value;

an offset generator coupled to the first amplifier, the second amplifier, the first ADC and the second ADC, and generating the offset value;

a first clock generator for generating a clock signal to control a sample timing of the first ADC and the second ADC;

a microprocessor coupled to the first ADC and the second ADC, said microprocessor processing the first and second digital output signals of the first and second ADC, respectively;

a second clock generator coupled to the microprocessor for generating a system time base;

a first memory coupled to the microprocessor, the memory containing an executable program for the microprocessor;

a second memory coupled to the microprocessor for storing data from and providing data to the microprocessor; and

a communications port coupled to the microprocessor for remote access of the microprocessor.

46. The energy information device of claim 45, wherein the transition detector comprises:

a filter having an input coupled to one output of the second amplifier to filter the voltage signal based on one of the plurality of voltages from the second amplifier;

a comparator coupled to the filter to compare a filtered output of the filter to a voltage;

an amplifier for amplifying an output if the comparator; and

an inverter for inverting an output of the amplifier and producing transition information relating to a voltage signal frequency,

wherein the transition information is supplied to the microprocessor, which determines the voltage signal frequency.

47. The energy information device of claim 45, wherein the communication port is at least one of an RS-232 port and an RS-485 port.

48. The energy information device of claim 45, wherein the communication port is coupled to a remote computer.

49. An energy information system mounted within a circuit breaker coupled between a power source and a load, the energy information system comprising:

a sensor to sense at least one of i) a voltage and ii) a current flowing between the power source and the load through the circuit breaker, the sensor having a voltage input range from about 50% to 125% of the voltage of the power source;

a voltage transformer to convert a line voltage of the power source to a voltage lower than the line voltage;

a transition detector to detect transitions of a sensed voltage from said sensor and to generate a transition signal, said transition detector comprising;

i) a filter having an input coupled to an output of the voltage transformer to filter an AC signal from the transformer;

ii) a comparator coupled to the filter to compare a filtered output of the filter to a voltage;

iii) an amplifier for amplifying an output of the comparator; and

iv) an inverter for inverting an output of the amplifier and producing a signal representative of a frequency of the AC signal;

a voltage shifter to bias the lower voltage above a ground potential by a predetermined voltage to produce a full-wave biased voltage waveform;

a mechanical counter to determine a first count value based on a total number of times the circuit breaker trips;

an interruption level counter to determine a second count value, the second count value indicating a current range flowing between the power source and the load when the circuit breaker trips, the interruption level counter includes a plurality of count values of respective ranges of current flows, the ranges of current flows selected from the group consisting of

i) the current flow being less than about 100% of a trip rating of the circuit breaker;

ii) the current flow being between about 100% and 300% of the trip rating of the circuit breaker;

iii) the current flow being between about 300% and 600% of the trip rating of the circuit breaker;

iv) the current flow being between about 600% and 900% of the trip rating of the circuit breaker, and

v) the current flow being greater than about 900% of the trip rating of the circuit breaker;

a fault counter to determine a third count value, the third count value indicating a count of a fault condition that trips the circuit breaker, the fault condition being at least one of;

i) an overload fault;

ii) a short time fault;

iii) an instantaneous fault; and

iv) a ground fault;

an energy information controller coupled to the sensor, the transition detector, the interruption level counter, and the voltage shifter, the energy information controller measures i) the current flow through the circuit breaker when the circuit breaker trips and interrupts the current flow between the power source and the load, and ii) the full-wave biased voltage to determine a plurality of energy related parameters using an AC signal frequency based on the transition signal;

a keypad coupled to the energy information controller to enter a user input, the user input for controlling at least one of the circuit breaker and a display;

a memory to store a date of manufacture of the circuit breaker;

the display coupled to the energy information controller to display at least one of i) the plurality of energy related parameters and ii) the date of manufacture, of the circuit breaker responsive to the user input, the plurality of energy related parameters including;

a) an energy demand calculated according to the following equation;

$\frac{\underset{n=1}{\overset{T_{\mathrm{PRG}}}{\sum <br><br>}}<br><br>\left(\frac{I_A+I_B+I_C}{3}\right)}{T_{\mathrm{PRG}}}=\mathrm{AmpDemand}$

where

T_PRG is a programmable demand period, and

I_A, I_B and I_C are phase currents for phases A, B and C, respectively; and

b) a plurality of RMS parameters measured over a range of harmonics of a fundamental frequency of the power source based on at least one of the voltage, the current and the frequency, over a predetermined period of time, the range of harmonics including up to at least about a 19th harmonic of the fundamental frequency;

a security controller for selectively allowing access of the energy information system by the keypad; and

a communication port including at least one of an RS-232 communication port and an RS485 communication port, the communication ports coupled to the energy information controller to selectively communicate at least one of the plurality of energy related parameters and the date of manufacture to a remote terminal;

wherein the communication ports provide for upload and download of data between the remote terminal and the energy information controller;

the display displays the plurality of energy related parameters in one of a plurality of languages based on a user selection through at least one of the keypad and the communication port; and

the energy information system is field installable within the circuit breaker.