CN211876381U - Circuit for over-temperature protection of water heater, circuit for power supply of water heater and water heater - Google Patents
Circuit for over-temperature protection of water heater, circuit for power supply of water heater and water heater Download PDFInfo
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- CN211876381U CN211876381U CN202020137996.1U CN202020137996U CN211876381U CN 211876381 U CN211876381 U CN 211876381U CN 202020137996 U CN202020137996 U CN 202020137996U CN 211876381 U CN211876381 U CN 211876381U
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Abstract
The application relates to the technical field of water heaters and discloses a circuit for overheat protection of a water heater. The over-temperature protection circuit of the water heater comprises a relay and a thermal cut-off device, wherein a contact of the relay is connected with a direct current power supply circuit of a heating pipe of the water heater and used for controlling the on-off of the direct current power supply circuit of the heating pipe; the first end of the temperature break is connected with the first end of the relay coil, and the second end of the temperature break and the second end of the relay coil are both connected to a power supply. The safety of the water heater can be improved by adopting the over-temperature protection circuit of the water heater. The application also discloses a circuit and water heater of water heater power supply.
Description
Technical Field
The application relates to the technical field of water heaters, for example, to a circuit for over-temperature protection of a water heater, a circuit for power supply of the water heater and the water heater.
Background
At present, a closed water heater is definitely specified in the safety standard of water storage type electric water heaters in China to be provided with a thermal cut-off device, and the action of the thermal cut-off device is ensured to cut off a power supply in time when the water heater is controlled abnormally through a switch separated from the adjusting function of a thermal controller. At present, in order to prevent accidents such as explosion and fire caused by overhigh temperature due to continuous heating of a water heater, a thermal cut-off device is generally connected in series in a heating circuit of the water heater. Under normal conditions, the temperature controller does not act, the heating circuit of the water heater is in a connected state, only when the first-stage temperature controller fails, the heating pipe of the water heater continues to heat, when the internal temperature of the water heater exceeds a set value, the internal contact of the thermostat is separated, and the heating circuit is disconnected with the thermostat to stop heating.
The electricity consumption of residents in China generally adopts 220V alternating current, a temperature cut-off device adopted by an alternating current power supply water heater is only suitable for an alternating current circuit, when the power supply mode is changed into direct current power supply, a heating circuit of the water heater adopts 280V-400V direct current, the current under the normal working state is generally larger than 10A, and the alternating current temperature cut-off device cannot normally work under the direct current power supply mode. In the prior art, a temperature controller, a temperature limiter and a relay are connected in series in a control circuit to control an electric heating tube.
In the process of implementing the embodiments of the present disclosure, it is found that at least the following problems exist in the related art:
the switch of the temperature limiting function is the same as the switch of the temperature adjusting function, and the safety of the water heater is lower.
SUMMERY OF THE UTILITY MODEL
The following presents a simplified summary in order to provide a basic understanding of some aspects of the disclosed embodiments. This summary is not an extensive overview nor is intended to identify key/critical elements or to delineate the scope of such embodiments but rather as a prelude to the more detailed description that is presented later.
The embodiment of the disclosure provides a circuit for over-temperature protection of a water heater, a circuit for power supply of the water heater and the water heater, so as to solve the technical problem of low safety of the water heater.
In some embodiments, the circuit for water heater over-temperature protection comprises:
the contact of the relay is connected with a direct current supply circuit of a heating pipe of the water heater and used for controlling the on-off of the direct current supply circuit of the heating pipe;
and the first end of the temperature breaker is connected with the first end of the relay coil, and the second end of the temperature breaker and the second end of the relay coil are both connected to a power supply.
In some embodiments, the circuit for supplying power to the water heater comprises a controller and the circuit for protecting the water heater from over-temperature provided by the previous embodiments; the controller is connected with a direct current supply circuit of a heating pipe of the water heater and used for adjusting the temperature of the heating pipe.
In some embodiments, the water heater comprises a heating pipe and the circuit for protecting the water heater from over-temperature provided by the previous embodiments, or the water heater comprises a heating pipe and the circuit for supplying power to the water heater provided by the previous embodiments.
The circuit of the water heater excess temperature protection that this disclosed embodiment provided, circuit and water heater of water heater power supply can realize following technological effect:
when the temperature of the water heater is overhigh, an independent relay is disconnected through the thermal cut-off device. When a fault occurs in the temperature control circuit, for example, a relay in the temperature control circuit fails to cause the temperature of the water heater to be overhigh, the heating circuit can be disconnected, the overtemperature protection of the water heater is realized, and the safety of the water heater is improved.
The foregoing general description and the following description are exemplary and explanatory only and are not restrictive of the application.
Drawings
One or more embodiments are illustrated in drawings corresponding to, and not limiting to, embodiments in which elements having the same reference number designation are illustrated as similar elements and in which:
fig. 1 is a schematic circuit diagram of a power supply for a water heater provided in an embodiment of the present disclosure.
Reference numerals:
10. a circuit for overheat protection of the water heater; 11. a temperature cutoff device; 12. a relay; 13. a DC conversion circuit; 20. a DC power supply circuit; 21. heating a tube; 22. a controller; 23. a direct current power supply.
Detailed Description
So that the manner in which the features and elements of the disclosed embodiments can be understood in detail, a more particular description of the disclosed embodiments, briefly summarized above, may be had by reference to the embodiments, some of which are illustrated in the appended drawings. In the following description of the technology, for purposes of explanation, numerous details are set forth in order to provide a thorough understanding of the disclosed embodiments. However, one or more embodiments may be practiced without these details. In other instances, well-known structures and devices may be shown in simplified form in order to simplify the drawing.
The terms "comprising" and "having" and any variations thereof in the description and claims of the embodiments of the present disclosure are intended to cover non-exclusive inclusions.
As shown in fig. 1, a circuit 10 for overheat protection of a water heater provided by the embodiment of the present disclosure includes a relay 12 and a thermal cut-off device 11, wherein a contact of the relay 12 is connected to a dc power supply circuit 20 of a heating pipe 21 of the water heater, and is configured to control on/off of the dc power supply circuit 20 of the heating pipe 21; a first end of the thermostat 11 is connected with a first end of a coil of the relay 12, and a second end of the thermostat 11 and a second end of the coil of the relay 12 are both connected to a power source. The circuit 10 for protecting the water heater from the over-temperature is composed of the thermal cut-off device 11 and the relay 12 in the embodiment, the circuit 10 for protecting the water heater from the over-temperature does not have the function of temperature adjustment, but only has the function of over-temperature protection, when the temperature of the water heater is too high, the circuit 10 for protecting the water heater from the over-temperature works independently, and is not influenced by other circuits, for example, the temperature control circuit, so that the protection of the water heater is realized, and the safety of the water heater is improved.
The temperature control circuit in the embodiment of the disclosure includes a controller and a switching element thereof, the controller outputs a switching signal, and the switching element performs a switching-on operation or a switching-off operation after receiving the switching signal.
The circuit 10 for the over-temperature protection of the water heater in the embodiment of the disclosure is applied to a direct-current water heater. The connection of the contacts of the relay 12 with the dc power supply circuit 20 of the heating tube 21 means that one or two pairs of contacts of the relay 12 are connected to the dc power supply circuit 20 of the heating tube 21, for example, at any position in the dc power supply circuit 20 of the heating tube 21, a pair of contacts of the relay 12 are connected in series, when the contacts are closed, the dc power supply circuit 20 of the heating tube 21 is connected, the heating tube 21 starts to heat, when the contacts are opened, the dc power supply circuit 20 of the heating tube 21 is disconnected, and the heating tube 21 stops heating, and the pair of contacts may be a pair of normally open contacts or a pair of normally closed contacts; or, two power lines of the heating pipe 21 are respectively connected to the two pairs of contacts, two power output ends of the dc power supply circuit 20 are also respectively connected to the two pairs of contacts, the two pairs of contacts are both normally open contacts or normally closed contacts, when the two pairs of contacts are closed, the dc power supply circuit 20 of the heating pipe 21 is switched on, the heating pipe 21 starts to heat, and when the two pairs of contacts are opened, the dc power supply circuit 20 of the heating pipe 21 is switched off, and the heating pipe 21 stops heating.
The heating pipe 21 is a direct-current heating pipe. Optionally, the rated voltage of the heating tube 21 is 375V, and the rated power of the heating tube 21 is 5000W. The longer the heating pipe 21 is energized, the higher the temperature thereof.
The thermostat 11 includes a temperature sensor therein, and can measure the temperature of the water heater or the temperature of the heating pipe 21 in the water heater.
Optionally, the normally open contacts of the relay 12 are connected in series to the dc supply circuit 20 of the heating tube 21. In a conventional ac-powered water heater, the thermostat 11 is connected in series to a power supply circuit of the heating pipe 21, and when the water temperature of the water heater is lower than a set temperature, the thermostat 11 is in an on state, that is, in the conventional technology, when a temperature control circuit of the water heater normally works, the over-temperature protection circuit is always in one state, and it is impossible to distinguish whether the over-temperature protection circuit is in a normal on state or in a faulty on state, which is not favorable for detecting whether the over-temperature protection circuit can normally work. In the embodiment of the present disclosure, when the water temperature of the water heater is lower than the set upper limit temperature, for example, the water temperature of the heater is lower than 97 ℃, the thermal cut-off 11 is turned on, the normally open contact of the relay 12 is closed, and the dc power supply circuit 20 may be controlled by the temperature control circuit; when the water temperature of the water heater is greater than or equal to the set upper limit temperature, for example, the water temperature of the water heater is greater than or equal to 97 ℃, the thermal cut-off 11 is disconnected, the normally open contact of the relay 12 is opened, the direct current power supply circuit 20 is forced to be disconnected, and the direct current power supply circuit 20 is not controlled by the temperature control circuit. It can be seen that when the water heater is powered on and the water temperature of the water heater is lower than the set temperature, the normally open contact of the relay 12 is closed, so that the relay 12 cannot be always in one state, when the relay 12 breaks down, the water heater cannot be heated normally, the fault of the relay 12 can be found conveniently in time, and the safety of the water heater is further improved.
The electricity consumption of residents in China generally adopts 220V alternating current, a thermostat 11 adopted by an alternating current power supply water heater is only suitable for an alternating current circuit, when the power supply mode is changed into direct current power supply, a heating circuit of the water heater adopts 280V-400V direct current, the current in a normal working state is generally larger than 10A, and the alternating current thermostat 11 cannot normally work in the direct current power supply mode. If the conventional idea in the ac-powered water heater is adopted, the ac thermostat 11 needs to be replaced by the dc thermostat 11, but the conventional technology does not match the dc thermostat 11 with a voltage of 280V-400V and a voltage of more than 10A, and if a dc thermostat 11 with a voltage of 280V-400V and a voltage of more than 10A is designed, the size of the ac thermostat 11 is far larger than that of the conventional ac thermostat 11, and the cost of the ac thermostat 11 is far higher than that of the conventional ac thermostat 11.
In some modifications, the thermostat 11, the thermostat and the relay 12 are connected in series to form a control circuit, and the control circuit is powered by low-voltage direct current. In a conventional dc powered water heater, the thermostat 11 is connected in series in the power supply circuit, and the thermostat is also connected in series in the power supply circuit, i.e. in a conventional ac powered water heater, the thermostat 11 and the thermostat are connected in series. Therefore, the improved technology continues the technical idea of the conventional alternating current power supply water heater. However, when the thermostat adjusts the temperature of the heating pipe 21 in the dc water heater, the relay 12 needs to be repeatedly turned on and off, which easily causes deterioration of the relay 12 and makes the operation insensitive. Under the condition that the relay 12 has a fault, if the temperature of the water heater is too high, even if the on-off state of the control circuit is changed, the on-off state of the coil of the relay 12 is changed, because the relay 12 is aged and insensitive to motion, the on-off state of the contact of the relay 12 is not changed, the heating pipe 21 is continuously electrified, the heating pipe 21 is continuously heated, and the water temperature in the water heater is continuously increased, so that danger is caused.
The circuit 10 for the over-temperature protection of the water heater provided in the embodiment of the present disclosure is different from the technical idea of the conventional ac power supply water heater and the design idea of the foregoing improved technology, but the circuit 10 for the over-temperature protection of the water heater is formed by the thermostat 11 and the relay 12 independently, because the circuit for the over-temperature protection of the water heater is not frequently triggered, the electrical components in the circuit are not easily aged (compared with the aging speed of the temperature control circuit), and when the temperature of the heating pipe 21 is greater than or equal to the set upper limit temperature due to the failure of the temperature control circuit, or when the temperature of the water stored in the water heater is greater than or equal to the set upper limit temperature, the dc power supply circuit 20 for the heating pipe 21 can be successfully cut off, so that the heating pipe 21 stops working, and the safety of the water heater.
Optionally, the thermostat 11 is a dc thermostat 11 or an ac thermostat 11. When the thermal cut-off 11 is an ac thermal cut-off 11, the ac thermal cut-off 11 in the prior art can be used, that is, the ac thermal cut-off 11 in the prior art is used to realize the over-temperature protection of the dc power supply water heater; when the thermostat 11 is a dc thermostat 11, a 5V, 12V, or 24V dc thermostat 11 may be selected.
Optionally, the circuit 10 for protecting the water heater from over-temperature further includes a dc conversion circuit 13, a first end of an output end of the dc conversion circuit 13 is connected to a second end of the thermal breaker 11, and a second end of the dc conversion circuit 13 is connected to a second end of the coil of the relay 12. The dc conversion circuit 13 converts the high-voltage dc power or the high-voltage ac power into a low-voltage dc power, for example, converts a high-voltage dc power of 280V to 400V into a dc power of 5V, 12V, or 24V. The direct current conversion circuit 13 supplies power to the relay 12, when the thermal cut-off 11 is switched on, a coil of the relay 12 is electrified, an internal armature is attracted, a normally open contact of the relay 12 is closed, and a normally closed contact of the relay 12 is opened; when the thermal cut-off 11 is opened, the coil of the relay 12 is powered down, the internal armature is recovered, the normally open contact of the relay 12 is opened, and the normally closed contact of the relay 12 is closed. The circuit 10 for overtemperature protection of a water heater is provided with a dc conversion circuit independent of the dc supply circuit 20, so that the electrical components used in the circuit 10 for overtemperature protection of a water heater are not affected by the dc supply circuit 20.
Alternatively, the output voltage of the dc conversion circuit 13 is less than or equal to 50V. For example, the output voltage of the dc conversion circuit 13 is 5V, 12V, 24V, or 48V. When the dc converter circuit 13 is used to supply power, not only the dc thermostat 11 but also the ac thermostat 11 can operate normally.
In some application scenes, after the water heater is powered on in a standby state, the circuit 10 of the over-temperature protection of the water heater is switched on, the temperature sensor of the thermostat 11 detects the temperature of the heating pipe 21 or the temperature of water stored in the water heater, whether the temperature is higher than a set upper limit temperature is judged, when the temperature is lower than the set upper limit temperature, the thermostat 11 is in a switched-on state, at the moment, the circuit 10 of the over-temperature protection of the water heater is continuously powered on, a coil of the relay 12 generates electromagnetic force, a normally open contact of the relay 12 is closed, a power supply circuit of the heating pipe 21 is switched on, and the heating pipe; when the temperature is equal to or higher than the set upper limit temperature, the thermal cut-off device 11 is disconnected, the circuit 10 for protecting the water heater from the over-temperature is disconnected, no current passes through the coil of the relay 12, the electromagnetic force disappears, the normally open contact of the relay 12 is disconnected, the power supply circuit of the heating pipe 21 is disconnected, and the heating pipe 21 stops working. The temperature of the heating pipe 21 or the temperature of the water stored in the water heater is prevented from continuously rising, so that the water heater is in a safe state. After the thermal cut-off device 11 is disconnected, the water heater is restored to the standby state through manual reset.
The embodiment of the present disclosure provides a circuit for supplying power to a water heater, which includes a controller 22 and the circuit 10 for protecting the water heater from over-temperature provided in the foregoing embodiment; the controller 22 is connected to the dc power supply circuit 20 of the heating pipe 21 of the water heater, and is used for adjusting the temperature of the heating pipe 21. For example, the longer the time for which the heating pipe 21 is controlled to be energized, the higher the temperature of the heating pipe 21; the shorter the time for which the heating pipe 21 is controlled to be energized, the lower the temperature of the heating pipe 21. When the water temperature of the water heater is lower than the set temperature, for example, the water temperature of the water heater is lower than 60 ℃, the controller 22 connects the direct current power supply circuit 20 of the heating pipe 21; when the water temperature of the water heater is greater than or equal to the set temperature, for example, the water temperature of the water heater is equal to or higher than 60 ℃, the controller 22 disconnects the dc power supply circuit 20 of the heating pipe 21. In the circuit for supplying power to the water heater, the circuit 10 for protecting the overtemperature of the water heater is independent of the circuit where the controller 22 is located, and the controller 22 controls the power on and off of the heating pipe 21 by controlling the on and off of a switching device, for example, by controlling the power on and off of a coil of the relay 12, changing the closing and opening of a contact of the relay 12, and controlling the power on and off of the heating pipe 21. After the water heater is powered on, the use frequency of the switching device controlled by the controller 22 is far greater than the use frequency of the relay 12 in the circuit 10 for over-temperature protection of the water heater, so that the service life of the relay 12 in the circuit 10 for over-temperature protection of the water heater is far longer than the service life of the switching device controlled by the controller 22, and thus, after the switching device controlled by the controller 22 breaks down, the circuit 10 for over-temperature protection of the water heater can still work normally, and after the water temperature in the water heater is ultrahigh and sets the upper limit temperature, the direct current supply circuit 20 of the heating pipe 21 can be successfully disconnected, and the safety of the water heater is improved.
Optionally, the circuit for supplying power to the water heater further includes a dc power supply 23, the dc power supply 23 is connected to the heating pipe 21 of the water heater to form the dc power supply circuit 20, and the output voltage of the dc power supply 23 is 280V to 400V. The dc power supply 23 is a power adapter, and outputs a dc power of 280V to 400V after inputting electric energy meeting the requirement. Under the condition of supplying power by the direct current power supply 23, the heating pipe 21 can work normally, but the existing alternating current thermal breaker 11 cannot work normally, and even a serious arc discharge phenomenon occurs. The existing alternating current thermal breaker 11 is arranged in the circuit 10 for the over-temperature protection of the water heater, the circuit 10 for the over-temperature protection of the water heater is independent of the direct current power supply circuit 20, and appropriate voltage is configured for the circuit 10 for the over-temperature protection of the water heater, so that the existing alternating current thermal breaker 11 works normally, the over-temperature protection of the water heater is realized by using the existing alternating current thermal breaker 11, and the safety of the water heater is improved.
Alternatively, the output terminal of the dc power supply 23 is connected to the input terminal of the dc conversion circuit 13. The direct current power supply 23 not only supplies power to the heating pipe 21, but also supplies power to the circuit 10 for the over-temperature protection of the water heater.
The embodiment of the present disclosure provides a water heater, which includes a heating pipe 21 and the circuit 10 for protecting the water heater from over-temperature provided by the foregoing embodiment, or includes a heating pipe 21 and the circuit for supplying power to the water heater provided by the foregoing embodiment. In the water heater, the thermal cut-off device 11 and the relay 12 form a circuit 10 for protecting the water heater from the over-temperature, the circuit 10 for protecting the water heater from the over-temperature does not have the function of temperature adjustment and only has the function of over-temperature protection, and when the temperature of the water heater is too high, the circuit 10 for protecting the water heater from the over-temperature independently works and is not influenced by other circuits, for example, the circuit is not influenced by a temperature control circuit, so that the protection of the water heater is realized, and the safety of the water heater is improved.
It will be understood that the present disclosure is not limited to the circuits that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.
Claims (10)
1. A circuit for over-temperature protection of a water heater, comprising:
the contact of the relay is connected with a direct current supply circuit of a heating pipe of the water heater and used for controlling the on-off of the direct current supply circuit of the heating pipe;
and the first end of the temperature breaker is connected with the first end of the relay coil, and the second end of the temperature breaker and the second end of the relay coil are both connected to a power supply.
2. The circuit of claim 1, wherein the thermostat is a dc thermostat or an ac thermostat.
3. The circuit of claim 1, wherein the normally open contacts of the relay are connected in series into the dc supply circuit of the heater tube.
4. The circuit of claim 1, 2 or 3, further comprising a dc conversion circuit, wherein a first terminal of an output terminal of the dc conversion circuit is connected to a second terminal of the thermal interrupter, and wherein a second terminal of the dc conversion circuit is connected to a second terminal of the relay coil.
5. The circuit of claim 4, wherein the output voltage of the DC conversion circuit is less than or equal to 50V.
6. The circuit of claim 5, wherein the output voltage of the DC conversion circuit is 5V, 12V, 24V or 48V.
7. A circuit of water heater power supply, includes the controller, its characterized in that still includes:
a circuit for over-temperature protection of a water heater as claimed in any one of claims 1 to 6;
the controller is connected with a direct current supply circuit of a heating pipe of the water heater and used for adjusting the temperature of the heating pipe.
8. The circuit of claim 7, further comprising:
and the direct current power supply is connected with the heating pipe of the water heater to form a direct current power supply circuit, and the output voltage of the direct current power supply is 280-400V.
9. The circuit of claim 8, wherein the output of the dc power source is connected to the input of the dc converter circuit.
10. A water heater comprising a heating pipe, characterized by further comprising a circuit for water heater over-temperature protection according to any one of claims 1 to 6, or a circuit for water heater power supply according to claim 7, 8 or 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020137996.1U CN211876381U (en) | 2020-01-20 | 2020-01-20 | Circuit for over-temperature protection of water heater, circuit for power supply of water heater and water heater |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020137996.1U CN211876381U (en) | 2020-01-20 | 2020-01-20 | Circuit for over-temperature protection of water heater, circuit for power supply of water heater and water heater |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN211876381U true CN211876381U (en) | 2020-11-06 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202020137996.1U Active CN211876381U (en) | 2020-01-20 | 2020-01-20 | Circuit for over-temperature protection of water heater, circuit for power supply of water heater and water heater |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN211876381U (en) |
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2020
- 2020-01-20 CN CN202020137996.1U patent/CN211876381U/en active Active
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