SG180118A1 - Current leakage circuit breaker with self-test function for water heater - Google Patents
Current leakage circuit breaker with self-test function for water heater Download PDFInfo
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- SG180118A1 SG180118A1 SG2011076395A SG2011076395A SG180118A1 SG 180118 A1 SG180118 A1 SG 180118A1 SG 2011076395 A SG2011076395 A SG 2011076395A SG 2011076395 A SG2011076395 A SG 2011076395A SG 180118 A1 SG180118 A1 SG 180118A1
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- current leakage
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- 238000012360 testing method Methods 0.000 title claims abstract description 90
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 38
- 230000002159 abnormal effect Effects 0.000 claims abstract description 74
- 238000000034 method Methods 0.000 claims abstract description 18
- 238000010438 heat treatment Methods 0.000 claims abstract description 16
- 238000001514 detection method Methods 0.000 claims abstract description 8
- 230000008569 process Effects 0.000 claims abstract description 7
- 238000004804 winding Methods 0.000 claims description 13
- 230000008030 elimination Effects 0.000 claims description 4
- 238000003379 elimination reaction Methods 0.000 claims description 4
- 239000004020 conductor Substances 0.000 description 13
- 238000010586 diagram Methods 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 230000004397 blinking Effects 0.000 description 2
- 230000004907 flux Effects 0.000 description 2
- 230000007935 neutral effect Effects 0.000 description 2
- 206010069808 Electrical burn Diseases 0.000 description 1
- 206010014405 Electrocution Diseases 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 238000010616 electrical installation Methods 0.000 description 1
- 231100001261 hazardous Toxicity 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 230000007257 malfunction Effects 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
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- Instantaneous Water Boilers, Portable Hot-Water Supply Apparatuses, And Control Of Portable Hot-Water Supply Apparatuses (AREA)
Abstract
CURRENT LEAKAGE CIRCUIT BREAKER WITH SELF-TEST FUNCTION FOR WATER HEATERA water heater (100) having a self-testing current leakage circuit breaker (10)5 comprises at least one heating means (20), a heater electronic controller (30), a water supply controller (40). The self-testing current leakage circuit breaker (10) electrically connected to a source of alternating current supply (60) for interrupting current supply to the heating means (20) when a fault condition has occurred and comprises a current leakage sensing component (11) for sensing abnormal current10 flows generated by leakage currents and generating voltage if abnormal current flows are sensed, an abnormal current leakage determination component (12) electrically connected to the current leakage sensing component (11) for determining whether abnormal current flows of sufficient magnitude and duration have occurred, an electrical current interrupting component (13) to disable the15 alternating current supply (60) upon detection of a fault. Furthermore, a circuit breaker testing component (14) that automatically test the functionality of the abnormal current leakage determination component (12) and the electrical current interrupting component (13); and a status indicator to indicate the user of the functionality condition of the abnormal current leakage determination component20 (12) and the electrical current interrupting component (13) upon completion of the self-testing process.The Most Illustrative Drawing: Figure 2
Description
~ he . . ) oT ) - - | t159159* : 1
CURRENT LEAKAGE CIRCUIT BREAKER WITH SELF -TEST
FUNCTION FOR WATER HEATER
The present invention relates to a current leakage circuit breaker device with self- test function for water heater. More particularly, the present invention relates to a self-testing current leakage circuit breaker with status indicators to alert users any current leakage and malfunctioning of the current leakage circuit breaker of an electric water heater.
Most of the electrical installation systems have a relatively high earth impedance.
These systems are dangerous and risky in case of a live to earth fault current flow.
These risks can be significantly reduced by the use of a current leakage circuit breaker. The current leakage circuit breaker makes these systems more safer by cutting the power if the dangerous situations happen. Thus, it is common to provide current leakage circuit breakers for main electrical appliances for current leakage protection.
Typical current leakage circuit breaker devices are designed to trip in response to ~ the detection of hazardous ground fault currents at an AC load of the devices.
Generally, the ground fault occurs when a person comes into contact electrically - scone with a hot conductor of the AC load and an earth ground at the similar time, a situation which can result in electrocution or electrical burns. The current leakage circuit breaker device detects this situation by using a sensing transformer to detect an imbalance between the currents flowing in the hot and neutral conductors of an
AC supply, as will happen when a portion of the current on the hot conductor is being diverted to the earth ground. When the imbalance is detected, a circuit breaker relay within the current leakage circuit breaker device is immediately tripped to an open condition, and removing all power from the load (electrical appliance).
The lifespan of an electrical appliance can be expected in decades, however there is no certainty that an current leakage circuit breaker will work properly over that time interval without default. Electronic parts and insulation will age from time to time and this will lead to a degradation in its performance. High current demands through the electronic parts, even in normal use, can cause the contacts of the circuit breaker in the current leakage circuit breaker to weld together, eventually preventing the circuit breaker from opening even if a fault is correctly detected.
Even an accidental lightning strike can permanently damage the electronic parts of an current leakage circuit breaker. Although users should periodically test current leakage circuit breaker devices, a manual test can give misleading results or be misinterpreted by the user. In current day, for current leakage circuit breaker devices that are provided with manual test buttons, there is no way to ensure that if they are tested and are replaced if defective. Sometimes, the user might also forget to use the manual test button of the current leakage circuit breaker during the usage of the electrical appliance.
Accordingly, there is a need for a self-testing feature in current leakage circuit breaker devices for such as electric water heater that is automatic, that is periodic,
and that disable the power supply if the device cannot afford protection from a ground fault or current leakage. Furthermore, there is a need for status indicators incorporated with the current leakage circuit breaker to provide alert to users of any current leakage and malfunctioning of the current leakage circuit breaker.
Accordingly, to solve the disadvantages and drawbacks of the prior art, there is provided a water heater having a self-testing current leakage circuit breaker, which essentially comprises at least one heating means, a heater electronic controller electrically connected to the heating means, a water supply controller electrically connected to a water supply means, and the self-testing current leakage circuit breaker electrically connected to a source of alternating current supply for interrupting current supply to the heating means when a fault condition has occurred. The self-testing current leakage circuit breaker comprises a current leakage sensing component for sensing abnormal current flows generated by leakage currents and generating voltage if abnormal current flows are sensed, an abnormal current leakage determination component electrically connected to the current leakage sensing component for determining whether abnormal current flows of sufficient magnitude and duration have occurred, an electrical current interrupting component electrically connected to the abnormal current leakage determination component to disable the alternating current supply upon detection of a fault. Furthermore, a circuit breaker testing component is electrically connected to the abnormal current leakage determination component that automatically test the functionality of the abnormal current leakage determination component and the electrical current interrupting component, and a status indicator is electrically connected to the circuit breaker testing component to indicate the user of the functionality condition of the abnormal current leakage determination component and the electrical current interrupting component upon completion of the self-testing process.
It is an object of the present invention to provide the self-testing current leakage circuit breaker further comprises an reset component electrically connected to the abnormal current leakage determination component that manually resets the electrical current interrupting component on elimination of the fault condition.
It is another object of the invention to provide the self-testing current leakage circuit breaker further comprises manual test component electrically connected to the abnormal current leakage determination component for manually testing the proper operation of the abnormal current leakage determination component,
It is yet another object of the invention to provide upon power on, the circuit breaker testing component to initialize one-time program routine by generating a test leakage current through a test loop wire to the current sense transformer and the secondary winding of current sense transformer to simulate a leakage current operation, and de-energise a power relay’s coil to open circuit and cut off the alternating current supply.
It is yet another object of the invention to provide a method of self-testing for current leakage circuit breaker of a water heater comprising the steps of: (a) sensing abnormal current flows generated by leakage currents via a current leakage sensing component to generate voltage;
(b) determining whether abnormal current flows of sufficient magnitude and duration have occurred via an abnormal current leakage determination component; (c) employing an electrical current interrupting component that disable the alternating current supply upon detection of a fault; (d) employing a circuit breaker testing component which is electrically connected to the abnormal current leakage determination component that automatically test the functionality of the abnormal current leakage determination component and the electrical current interrupting component; and (¢) employing a status indicator that indicates the user of the functionality condition of the abnormal current leakage determination component and the - electrical current interrupting component upon completion of the self-testing process.
It is yet another object of the invention to provide the circuit breaker testing component to receive a load supply signal from the alternating current supply and } 15 compare it with an output status from the abnormal current leakage determination component to determine the condition of the abnormal current leakage oo determination component and the electrical current interrupting component.
Other objects and advantages of the present invention will become apparent from the detailed description provided hereinafter. It should be understood however that the detailed description and specific examples, while indicating preferred embodiments of the invention, are intended for purposes of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
Figure 1 shows a block diagram of a-water heater components having a self-testing current leakage circuit breaker in a preferred embodiment of the invention.
Figure 2 shows a block diagram of a self-testing current leakage circuit breaker in a preferred embodiment of the invention.
The present invention is to provide a water heater (100) having a self-testing current leakage circuit breaker (10) comprises at least one heating means (20), a heater electronic controller (30), a water supply controller (40). The self-testing current leakage circuit breaker (10) electrically connected to a source of alternating current supply (60) for interrupting current supply to the heating means (20) when
To a fault condition has occurred and comprises a current leakage sensing component (11) for sensing abnormal current flows generated by leakage currents and generating voltage if abnormal current flows are sensed, an abnormal current leakage determination component (12) electrically connected to the current leakage sensing component (11) for determining whether abnormal current flows of sufficient magnitude and duration have occurred, an electrical current interrupting component (13) that disable the alternating current supply (60) upon detection of a fault. Furthermore, a circuit breaker testing component (14) that automatically test the functionality of the abnormal current leakage determination component (12) and the electrical current interrupting component (13); and a status indicator to indicate the user of the functionality condition of the abnormal current leakage determination component (12) and the electrical current interrupting component : (13) upon completion of the self-testing process. The electrical current interrupting component (13) comprises a relay (31).
Referring to Figure 1, there can be seen the water heater (100) components having a self-testing current leakage circuit breaker in a preferred embodiment of the invention. A source of alternating current supply (60), preferably 220-240V is provided. The incoming conductors from the source are provided with one : ungrounded conductor known as live conductor and another grounded conductor known as neutral conductor. Conductors pass through the self-testing current leakage circuit breaker (10) and thereby operate the self-testing current leakage circuit breaker (10). A thermal cutout (80) is connected to the self-testing current leakage circuit breaker (10) to open the electrical circuit in the event of a high temperature. A water supply controller (40) is electrically connected to the thermal cutout (80) and the self-testing current leakage circuit breaker (10) to draw the power from the source of alternating current supply (60) to provide control for a water supply means (50). The water supply means (50) having a motor to pump in water to be heated by the heating means (20). Furthermore, a speed control : potentiometer is electrically connected to the water supply controller (40) to control the speed of the water flow from the water supply means (50).
Further referring to Figure 1, a heater electronic controller (30) is electrically connected to the heating means (20) to control the temperature to be generated by the heating means (20). A triode for alternating current (TRIAC) (110) is electrically connected to the heater electronic controller (30) and the heating means (20) as a switch to control the percentage of current that flows through the TRIAC (110) to the heating means (20). A flow switch (90) is electrically connected to the thermal cutout (80) and the heater electronic controller (30) to sense the flow of water passing through its valve body and to send an electrical control signal to the heater electronic controller (30) to control the TRIAC (110) and the water supply means (50).
Referring to Figure 2, there can be seen the block diagram of a self-testing current leakage circuit breaker in a preferred embodiment of the invention. The current leakage sensing component (11) comprises a current sense transformer (21) and a secondary winding (22) of the current sense transformer. The incoming conductors from the source are AC(L) (60a) and AC(N) (60b). These conductors AC(L) (60a) and AC(N) (60b) will pass through the zero-phase current sensor transformer 21) and act as primary winding. The secondary winding (22) of the current sense transformer will connect to the abnormal current leakage determination component (12) which may filter, amplify and process the output voltage from secondary winding (22). In normal operation which no leakage current occurred, the same amount of current will flow through conductors AC(L) (60a) and AC(N) (60b) in opposite direction. This will cause near zero flux on the current sense transformer (21) and generate near zero voltage on the secondary winding (22). This near zero voltage will make the power relay’s (31) coil to energize through a transistor and the load (heating means) will get current supply from contacts (31a, 31b).
Upon power on, the circuit breaker testing component (14) will initialize one-time program routine to determine on the abnormal current leakage determination component (12) and the electrical current interrupting component (13) functions.
Under this routine, the circuit breaker testing component (14) generates a test leakage current through a test loop wire (23) to the current sense transformer (21) and the secondary winding of current sense transformer (22) to simulate a leakage current operation. Upon detection of the voltage on the secondary winding (22) by the abnormal current leakage determination component(12), the power relay’s (31)
coil will be de-energised to open circuit and cut off the current supply from contacts (31a, 31b). At the same time, the circuit breaker testing component (14) will monitor condition of the load AC conductors (33a, 33b) which generate the load supply signal, to the circuit breaker testing component (14) by a connection (34). It will then check against the load supply signal with an output status from the abnormal current leakage determination component (12) through a connection (35) to determine the condition of the abnormal current leakage determination component (12) and the electrical current interrupting component (13). In normal operation, the load supply signal and the output status should tally with each other.
In case not, then the circuit breaker testing component (14) will determine that there is malfunction on the abnormal current leakage determination component (12) or the electrical current interrupting component (13). The routine will continue checking to confirm the result. Preferably, the status indicator device ( 15) comprises a plurality of bi-color light-emitting diodes (LEDs). Each bi-color LED consists of a red LED and a green LED in a single package. Upon completion, the abnormal current leakage determination component (12) will indicate the pass result by turn on permanently the green LEDs with green light and fail result by turn on the red LEDs with the blinking red light. Under normal condition which green LEDs is on, the circuit breaker testing component (14) will complete the routine by automatically sending a reset signal to the abnormal current leakage determination component (12) to energise back the power relay and set back to normal operation. :
When there is leakage current on load portion, this will create imbalance flux on the current sense transformer (21) and generate non-zero output voltage on the secondary winding (22) of the current sense transformer. This voltage will input to the abnormal current leakage determination component (12) which will determine whether a leakage current of sufficient magnitude and duration has occurred. In case a leakage current is detected, then the abnormal current leakage determination component (12) will trigger a silicon controlled rectifier (SCR) which will turn off a transistor and at the same time, the power relay coils will de-energize and release open the relay contacts (31a, 31b). The red LEDs will start blinking,
Furthermore, the self-testing current leakage circuit breaker (10) further comprises a reset component (16) electrically connected to the abnormal current leakage determination component (12) that manually resets the electrical current interrupting component (13) on elimination of the fault condition. A manual test component (17) is electrically connected to the abnormal current leakage determination component (12) for manually testing the proper operation of the abnormal current leakage determination component (12). A power supply component (18) is electrically connected to the alternating current supply (60) to supply power to the abnormal current leakage determination component (12) and the circuit breaker testing component (14).
While several particularly preferred embodiments of the present invention have been described and illustrated, it should now be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. Accordingly, the following claims are intended to embrace such changes, modifications, and areas of application that are within the oo spirit and scope of this invention.
Claims (20)
1. A water heater (100) having a self-testing current leakage circuit breaker (10) comprising: at least one heating means (20); a heater electronic controller (30) electrically connected to the heating means (20); a water supply controller (40) electrically connected to a water supply means (50); and the self-testing current leakage circuit breaker (10) electrically connected to a source of alternating current supply (60) for interrupting current supply to the heating means (20) when a fault condition has occurred; the self-testing current leakage circuit breaker (10) comprising: a current leakage sensing component (11) for sensing abnormal current flows generated by leakage currents and generating voltage if abnormal current flows are sensed; an abnormal current leakage determination component (12) electrically connected to the current leakage sensing component (11) for determining whether abnormal current flows of sufficient magnitude and duration have occurred; an electrical current interrupting component (13) electrically connected to the abnormal current leakage determination component (12) to disable the alternating current supply (60) upon detection of a fault; characterized in that a circuit breaker testing component (14) is electrically connected to the abnormal current leakage determination component (12) to automatically test the functionality of the abnormal current leakage determination component (12) and the electrical current interrupting component (13); and a status indicator (15) is electrically connected to the circuit breaker testing component (14) to indicate the user of the functionality condition of the abnormal current leakage determination component (12) and the electrical current interrupting component (13) upon completion of the self-testing process.
2. A water heater (100) according to claim 1, wherein the self-testing current : leakage circuit breaker (10) further comprises a reset component (16) electrically abnormal connected to the abnormal current leakage determination component (12) that manually resets the electrical current interrupting component ( 13) on : elimination of the fault condition.
A A water heater (100) according to claim 1 or claim 2, wherein the self-testing current leakage circuit breaker (10) further comprises a manual test component (17) electrically connected to the abnormal current leakage determination component (12) for manually testing the proper operation of the abnormal current leakage : determination component (12).
4. A water heater (100) according to any one of claims 1 to 3, the self-testing current leakage circuit breaker (10) further comprises a power supply component (18) electrically connected to the alternating current supply (60) to supply power to the abnormal current leakage determination component (12) and the circuit breaker testing component (14). | :
5. A water heater (100) according to claim 1, wherein the status indicator device (15) comprises a plurality of bi-color light-emitting diodes (LEDs).
6. A water heater (100) according to claim 1, wherein the current leakage sensing component (11) comprises a current sense transformer (21) and a secondary winding (22) of the current sense transformer.
7. A water heater (100) according to claim 1, wherein the electrical current interrupting component (13) comprises a power relay (31).
8. A water heater (100) according to claim 6 or 7, wherein upon power on, the circuit breaker testing component (14) initializes one-time program routine by generating a test leakage current through a test loop wire (23) to the current sense transformer (21) and the secondary winding of current sense transformer (22) to simulate a leakage current operation, and de-energise a power relay’s (31) coil to open circuit and cut off the alternating current supply (60).
9. A water heater (100) according to claim 8, wherein when the circuit breaker testing component (14) receives a load supply signal from the alternating current supply (60) and compares it with an output status from the abnormal current leakage determination component (12) to determine the condition of the abnormal current leakage determination component (12) and the electrical current interrupting component (13).
10. A water heater (100) according to claim 8, wherein the circuit breaker testing component (14) completes the routine by automatically sending a reset signal to the abnormal current leakage determination component (12) to energise back the power relay and set back to normal operation.
I1. A method of self-testing for current leakage circuit breaker (10) of a water heater (100) comprising the steps of: (a) sensing abnormal current flows generated by leakage currents via a current leakage sensing component (11) to generate voltage; (b) determining whether abnormal current flows of sufficient magnitude and : duration have occurred via an abnormal current leakage determination component (12); (c) employing an electrical current interrupting component (13) that disable the alternating current supply (60) upon detection of a fault; (d) employing a circuit breaker testing component (14) which is electrically connected to the abnormal current leakage determination component (12) that
“oe 14 automatically test the functionality of the abnormal current leakage determination component (12) and the electrical current interrupting component (13); and (e) employing a status indicator (15) that indicates the user of the functionality condition of the abnormal current leakage determination component (12) and the electrical current interrupting component (13) upon completion of the self-testing process. oo
12. A method of claim 11, further comprising the step of employing a reset component (16) electrically connected to the abnormal current leakage determination component (12) that manually resets the electrical current interrupting component (13) on elimination of the fault condition.
13. A method of any one of claims 11 to 12, further comprising the step of employing a manual test component (17) electrically connected to the abnormal current leakage determination component (12) for manually testing the proper operation of the abnormal current leakage determination component (12).
14. A method of claim 11, further comprising the step of employing a power supply component (18) to supply power to the abnormal current leakage determination component (12) and the circuit breaker testing component (14).
15. A method of claim 11, wherein the step of employing a status indicator (15) comprises employing a plurality of bi-color light-emitting diodes (LEDs).
16. A method of claim 11, wherein the step of employing a current leakage sensing component (11) comprises employing a current sense transformer (21) and a secondary winding (22) of the current sense transformer.
: 17. A method of claim 11, wherein the step of employing a electrical current . interrupting component (13) comprises employing a power relay (31).
18. A method of claim 16 or 17, wherein the step of employing a circuit breaker testing component (14) comprising upon power on, Initializing one-time program routine by generating a test leakage current from the circuit breaker testing component (14) through a test loop wire (23) to the current sense transformer (21) and the secondary winding (22) of the current sense transformer to simulate a leakage current operation and de-energise a power relay’s (31) coil to open circuit and cut off the alternating current supply (60).
19. A method of claim 18, wherein the step of employing a circuit breaker testingcomponent (14) comprising receiving a load supply signal by the circuit breaker testing component (14) from the alternating current supply (60) and comparing it with an output status from the abnormal current leakage determination component (12) to determine the condition of the abnormal current leakage determination component (12) and the electrical current interrupting component (13).
20. A method of claim 18, wherein the step of employing the circuit breaker testing component (14) comprising completing the routine by automatically sending a reset signal to the abnormal current leakage determination component (12) to energise back the power relay (31) and set back to normal operation. )
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| MYPI2010004926A MY165119A (en) | 2010-10-20 | 2010-10-20 | Current leakage circuit breaker with self-test function for water heater |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| SG180118A1 true SG180118A1 (en) | 2012-05-30 |
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ID=46397688
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| SG2011076395A SG180118A1 (en) | 2010-10-20 | 2011-10-17 | Current leakage circuit breaker with self-test function for water heater |
Country Status (2)
| Country | Link |
|---|---|
| MY (1) | MY165119A (en) |
| SG (1) | SG180118A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103574907A (en) * | 2012-07-30 | 2014-02-12 | 宁波奥克斯空调有限公司 | Electric heating function control device for heat-pump water heater and control method of electric heating function control device |
-
2010
- 2010-10-20 MY MYPI2010004926A patent/MY165119A/en unknown
-
2011
- 2011-10-17 SG SG2011076395A patent/SG180118A1/en unknown
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103574907A (en) * | 2012-07-30 | 2014-02-12 | 宁波奥克斯空调有限公司 | Electric heating function control device for heat-pump water heater and control method of electric heating function control device |
| CN103574907B (en) * | 2012-07-30 | 2016-03-23 | 宁波奥克斯空调有限公司 | For control device and the control method thereof of the electric heating function of Teat pump boiler |
Also Published As
| Publication number | Publication date |
|---|---|
| MY165119A (en) | 2018-02-28 |
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