Overload warning and protection device and method and light control system

Abstract

The invention discloses an overload warning and protecting device and method and a light control system. The light control system comprises a power supply, a light-emitting device and a switch element. The overload warning and protecting device comprises a current detecting element and a control element. The current detection element is arranged on the power supply line and is suitable for detecting the current on the power supply line to generate a current detection signal. The control element is electrically coupled to the switch element and the current detection element, and is suitable for receiving the current detection signal to control the conduction state of the switch element. Wherein when the control element detects that the current is greater than the first threshold current and lasts for more than a first preset time, the control element periodically turns off and turns on the switch element, and when the control element detects that the current is greater than the second threshold current and the second threshold current is greater than the first threshold current, the control element permanently turns off the switch element.

Description

[0001] This invention relates to the technical field of lighting control, and more particularly to an overload warning and protection device and method suitable for lighting control systems. Background Technology

[0002] In general lighting fixtures, especially outdoor lighting fixtures, multiple lamps of different wattages are often connected to the same circuit. Because they are far from the power control terminal, it is not immediately apparent that the upper limit of the circuit's rated current has been reached. Since lamps have different wattages, questions such as "what wattage can be installed" and "how many lamps" often confuse people who lack electrical knowledge. Summary of the Invention

[0003] The system of this invention specifically addresses the above-mentioned problems by proposing an instant warning system that allows consumers to know whether the rated load has been exceeded without having to calculate the wattage themselves. Furthermore, it uses the flashing of all lights to force personnel to stop adding more lights, and cuts off the power supply within a certain percentage of overload, achieving instant warning and ensuring system safety.

[0004] This invention provides an overload warning and protection device applicable to a lighting control system. This lighting control system includes a power supply, a light-emitting device, and a switching element. The power supply provides power to the light-emitting device via a power supply line, and the switching element is located on the power supply line. The overload warning and protection device includes a current detection element and a control element. The current detection element is located on the power supply line and is adapted to detect a current on the power supply line to generate a current detection signal. The control element is electrically coupled to the switching element and the current detection element, and is adapted to receive the current detection signal and control the conduction state of the switching element according to the current detection signal. The control element also has a first threshold current, a second threshold current, and a first preset time, wherein the second threshold current is greater than the first threshold current. Specifically, when the control element detects a current greater than the first threshold current for a period exceeding the first preset time based on the current detection signal, the control element periodically turns the switching element off and on. When the control element detects a current greater than the second threshold current based on the current detection signal, the control element permanently turns the switching element off.

[0005] In one embodiment of the present invention, the light-emitting device may be an outdoor lamp or a Christmas lamp.

[0006] In one embodiment of the present invention, the control element may be a microcontroller (MCU).

[0007] In one embodiment of the present invention, the control element is provided with a second preset time, and the control element periodically turns the switching element on and off according to the first preset time and the second preset time. In a preferred embodiment, the first preset time is equal to the second preset time. In a preferred embodiment, when the control element detects that the current is greater than a first threshold current and continues to exceed the first preset time based on the current detection signal, the control element turns off the switching element and waits for the second preset time.

[0008] In one embodiment of the present invention, when the control element detects that the current is greater than the second threshold current based on the current detection signal, the control element turns off the switching element and enters a deactivated state.

[0009] In one embodiment of the present invention, the current detection signal is a voltage signal. The control element is provided with a first threshold voltage and a second threshold voltage, the first threshold voltage corresponding to a first threshold current and the second threshold voltage corresponding to a second threshold current. The control element compares the current detection signal with the first threshold voltage to determine whether the current is greater than the first threshold current.

[0010] In one embodiment of the present invention, the control element is provided with an analog-to-digital converter, which is adapted to convert the current detection signal into a numerical value and determine whether the current is greater than a first threshold current based on the numerical value.

[0011] This invention also provides an overload warning and protection method, applicable to an overload warning and protection device. The overload warning and protection device is applicable to a lighting control system. The lighting control system includes a power supply, a light-emitting device, and a switching element. The power supply supplies power to the light-emitting device via a power supply line, and the switching element is located on the power supply line. The overload warning and protection device includes a current detection element. This current detection element is located on the power supply line and is adapted to detect a current on the power supply line to generate a current detection signal. The overload warning and protection method of this invention includes: setting a first threshold current, a second threshold current, and a first preset time, wherein the second threshold current is greater than the first threshold current; receiving the current detection signal to detect the current; periodically turning off and on the switching element when the current is greater than the first threshold current and continues for more than the first preset time; and permanently turning off the switching element when the current is greater than the second threshold current.

[0012] This invention also provides a lighting control system. This lighting control system includes a power supply, a light-emitting device, a switching element, and an overload warning and protection device. The power supply provides power to the light-emitting device via a power supply line. The switching element is disposed on the power supply line. The overload warning and protection device is electrically coupled to the switching element and includes a current detection element and a control element. The current detection element is disposed on the power supply line and is adapted to detect a current on the power supply line to generate a current detection signal. The control element is electrically coupled to the switching element and the current detection element and is adapted to receive the current detection signal and control the conduction state of the switching element according to the current detection signal. The control element also has a first threshold current, a second threshold current, and a first preset time, wherein the second threshold current is greater than the first threshold current. When the control element detects a current greater than the first threshold current for a period exceeding the first preset time based on the current detection signal, the control element periodically turns the switching element off and on. When the control element detects a current greater than the second threshold current based on the current detection signal, the control element permanently turns the switching element off.

[0013] The overload warning and protection device and method provided by this invention can provide a real-time overload warning and protection mechanism for lighting. After power is supplied, the control element turns on the switching element to start supplying power to the light-emitting device. When the current exceeds a first threshold current and continues for more than a first preset time, the control element turns off the switching element and waits for a second preset time before turning the switching element on again. If the current is still greater than the first threshold current, the control element will repeat the above steps and turn off the switching element again. This repeated operation allows the switching element to be turned on and off periodically, causing the light-emitting device to flash, thus providing a real-time reminder to the installer or user of overload problems. Furthermore, if the current does not decrease but continues to increase, when the current exceeds a second threshold current, the control element will permanently turn off the switching element until the power supply to the overload warning and protection device is turned off and restarted, at which point the switching element can be turned on again to make the light-emitting device light up. In this way, it can be ensured that the light-emitting device will only operate normally when the current falls within its rated range; otherwise, the light-emitting device will flash to remind the user and cut off the power supply for protection when the current is too high. Attached Figure Description

[0014] The features and advantages of the present invention are described in detail below with reference to the accompanying drawings: Figure 1 This is a schematic diagram of a lighting control system with overload warning and protection devices according to an embodiment of the present invention; Figure 2 It uses waveform diagrams to show the relationship between the power supply's output voltage, the current on the power supply line, and the input voltage of the light-emitting device; Figure 3A flowchart of an overload warning and protection method according to an embodiment of the present invention; and Figure 4 show Figure 3 An embodiment of step S360 of the overload warning and protection method shown.

[0015] Symbol explanation: 20: Lighting control system 22: Power supply 24: Light-emitting device 26: Switching elements 28: Power supply line 100: Overload warning and protection device 120: Current detection element 140: Control element I1: Current S1: Current detection signal V1: Output voltage V2: Input voltage Is1: First threshold current Is2: Second threshold current td1: First preset time td2: Second preset time S320, S340, S360, S420, S430, S440, S450, S460, S470: Steps. Detailed Implementation

[0016] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention. The advantages and features of the present invention will become clearer from the following description and the claims. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clearly illustrate the embodiments of the present invention.

[0017] Figure 1 This is a schematic diagram of a lighting control system 20 with an overload warning and protection device 100 provided according to an embodiment of the present invention.

[0018] As shown in the figure, this overload warning and protection device 100 is applicable to the lighting control system 20 to prevent excessive current I1 from causing equipment damage or endangering personnel safety.

[0019] The lighting control system 20 includes a power supply 22, a light-emitting device 24, a switching element 26, and the aforementioned overload warning and protection device 100. The power supply 22 supplies power to the light-emitting device 24 via a power supply line 28, and the switching element 26 is located on the power supply line 28. In one embodiment, the light-emitting device 24 may be an outdoor light or a Christmas light, and the light-emitting device 24 may include a plurality of lamps connected in series. In one embodiment, any electrically controllable switching element 26, such as a relay, MOSFET, IGBT, TRIAC, silicon controlled rectifier (SCR), or other electronic components, is applicable to this invention.

[0020] The overload warning and protection device 100 includes a current detection element 120 and a control element 140. The current detection element 120 is disposed on the power supply line 28 and is adapted to detect a current I1 on the power supply line 28 to generate a current detection signal S1.

[0021] In one embodiment, the current sensing element 120 may be a current sensing resistor, a Hall current sensing element, or other electronic components suitable for detecting current I1 and converting it into a voltage signal (i.e., current sensing signal S1) for external interpretation.

[0022] The control element 140 is electrically coupled to the switching element 26 and the current sensing element 120, and is adapted to receive the current sensing signal S1 and control the conduction state of the switching element 26 according to the current sensing signal S1.

[0023] Please refer to the above as well. Figure 2 , Figure 2 The waveform diagram shows the relationship between the output voltage V1 of the power supply 22, the current I1 on the power supply line 28, and the input voltage V2 of the light-emitting device 24.

[0024] In this embodiment, the control element 140 is provided with a first threshold current Is1, a second threshold current Is2, a first preset time td1, and a second preset time td2. The second threshold current Is2 is greater than the first threshold current Is1.

[0025] After the power supply 22 provides power, the overload warning and protection device 100 receives power, and the control element 140 turns on the switching element 26 to start supplying power to the light-emitting device 24.

[0026] When the control element 140 detects that the current I1 is greater than the first threshold current Is1 based on the current detection signal S1, the control element 140 will start timing for a first preset time td1. If, within the first preset time td1, the current I1 detected by the current detection signal S1 drops below the first threshold current Is1, the control element 140 will return to its original normal operating state (e.g., Figure 2 (The state indicated by the middle arrow A).

[0027] If the current I1 is greater than the first threshold current Is1 and the state continues for more than a first preset time td1 (e.g.) Figure 2 (In the state indicated by the middle arrow B), the control element 140 will temporarily turn off the switch element 26 and wait for a second preset time td2 before turning the switch element 26 back on.

[0028] At this point, if the current I1 drops below the first threshold current Is1, the control element 140 will return to its original normal operating state. Next, if the current I1 exceeds the first threshold current Is1 again, the control element 140 will recalculate the first preset time td1.

[0029] Conversely, if the current I1 is continuously or normally greater than the first threshold current Is1, the control element 140 will periodically turn the switching element 26 off and on according to the first preset time td1 and the second preset time td2 (the working cycle of the switching element 26 will be close to the sum of the first preset time td1 and the second preset time td2), thereby causing the light-emitting device 24 to flash light to remind the user that the lighting control system 20 is in an overload (overcurrent) state.

[0030] To ensure that the user can clearly see that the light-emitting device 24 is flashing light, in a preferred embodiment, the aforementioned first preset time td1 and second preset time td2 are preferably between 0.3 seconds and 0.5 seconds, but are not limited thereto. Furthermore, in a preferred embodiment, the first preset time td1 can be set to be equal to the second preset time td2.

[0031] If the current I1 exceeds the first threshold current Is1 and continues to rise, it indicates that the aforementioned periodic shut-off of the switching element 26 has failed to effectively reduce the current I1. In this case, when the control element 140 detects that the current I1 exceeds the second threshold current Is2 based on the current detection signal S1, the control element 140 will permanently shut off the switching element 26. That is, the control element 140 will cease controlling the switching element 26 after shutting it off, and will only re-enable the switching element 26 and illuminate the light-emitting device 24 again when the system power supply (including the power supply to the overload warning and protection device 100) is turned off and restarted.

[0032] In one embodiment, when the control element 140 detects that the current I1 is greater than the second threshold current Is2 based on the current detection signal S1, the control element 140 can enter a disabled state after turning off the switching element 26. At this time, the control element 140 must be restarted by an externally input enable signal in order to turn on the switching element 26 and enable the power supply 22 to supply power to the light-emitting device 24.

[0033] In one embodiment, the control element 140 may be a microcontroller (MCU). The microcontroller can execute the judgment and control program of this invention through its built-in input / output (I / O), analog-to-digital converter (ADC), timer, pulse width modulation (PWM) control, and its built-in memory. However, this invention is not limited thereto.

[0034] If an analog comparison is used, the control element 140 can set a first threshold voltage and a second threshold voltage. The first threshold voltage corresponds to a first threshold current Is1, and the second threshold voltage corresponds to a second threshold current Is2. The control element 140 compares the current detection signal S1 with the first threshold voltage to determine whether the current I1 is greater than the first threshold current Is1, and compares the current detection signal S1 with the second threshold voltage to determine whether the current I1 is greater than the second threshold current Is2.

[0035] Specifically, if the current detection signal S1 is greater than the first threshold voltage, the control element 140 will generate a timing start signal to trigger the timer to start timing. If, within the first preset time td1 after the timing starts, the potential of the current detection signal S1 drops below the first threshold voltage, the control element 140 will reset the timer and return to its original normal operating state.

[0036] Conversely, if the potential of the current detection signal S1 is consistently higher than the first threshold voltage, when the first preset time td1 is reached, the timer will generate a trigger signal to notify the control element 140 to turn off the switching element 26, and simultaneously reset and recalculate the time. When the second preset time td2 is reached, another trigger signal will be generated to notify the control element 140 to turn the switching element 26 back on. In this way, the switching element 26 can be periodically turned off and on, thereby causing the light-emitting device 24 to flash.

[0037] Furthermore, if the potential of the current detection signal S1 is greater than the second threshold voltage before the timer calculates the first preset time td1, the control element 140 will immediately turn off the switching element 26 and enter the deactivated state, stopping the control of the switching element 26.

[0038] If a digital comparison is used for judgment, the control element 140 can preset a first threshold and a second threshold, corresponding to the first threshold current Is1 and the second threshold current Is2, respectively. Subsequently, the control unit can use an analog-to-digital converter to convert the current detection signal S1 into a numerical value, and compare this value with the first threshold and the second threshold to determine whether the current I1 is greater than the first threshold current Is1 or even greater than the second threshold current Is2.

[0039] In practical applications, the aforementioned power supply 22, switching element 26, and overload warning and protection device 100 can be installed indoors and electrically coupled to the outdoor lighting device 24 via power supply line 28. In this way, even if the user is indoors, they can detect the risk of overload in the lighting control system 20 by the flashing light of the lighting device 24.

[0040] Figure 3 This is a flowchart of an overload warning and protection method provided according to an embodiment of the present invention.

[0041] This invention also provides an overload warning and protection method, applicable to... Figure 1 The overload warning and protection device 100 is shown. This overload warning and protection device is applicable to a lighting control system 20. The lighting control system 20 includes a power supply 22, a light-emitting device 24, and a switching element 26. The power supply 22 supplies power to the light-emitting device 24 through a power supply line 28, and the switching element 26 is located on the power supply line 28. The overload warning and protection device 100 includes a current detection element 120 and a control element 140. The current detection element 120 is electrically coupled to the power supply line 28 and is adapted to detect the current I1 on the power supply line 28 to generate a current detection signal S1.

[0042] The overload warning and protection method in this embodiment includes the following steps.

[0043] First, as described in step S320, a first threshold current Is1 and a second threshold current Is2 are set, wherein the second threshold current Is2 is greater than the first threshold current Is1. This step can be performed by the control element 140. In one embodiment, the control element 140 may be configured with voltage levels or values ​​corresponding to the first threshold current Is1 and the second threshold current Is2 to facilitate subsequent comparison and judgment.

[0044] Subsequently, as described in step S340, a current detection signal S1 is received to detect the current I1. This step can be performed by the control element 140 via the current detection element 120.

[0045] Then, as described in step S360, when the current detection signal S1 shows that the current I1 is greater than the first threshold current Is1 and continues to exceed the first preset time td1, the switching element 26 is periodically turned off and turned on, and when the current detection signal S1 shows that the current I1 is greater than the second threshold current Is2, the switching element 26 is permanently turned off.

[0046] When the current detection signal S1 indicates that the current I1 is greater than the second threshold current Is2, the control element 140 will permanently shut off the switching element 26 until the power supply 22 of the system (including the overload warning and protection device 100) is turned off and restarted, at which point the light can be turned on again. In this way, in addition to providing an immediate warning when the load current is too high (exceeding the first threshold current Is1) and helping to maintain the load current within the rated range, it can also directly cut off the current when the load current is too large (exceeding the second threshold current Is2), preventing damage to the lighting control system 20.

[0047] Figure 4 show Figure 3 An embodiment of step S360 of the overload warning and protection method shown.

[0048] Following step S340, after receiving the current detection signal S1, as described in step S420, the current I1 is confirmed to be greater than the first threshold current Is1 based on the current detection signal S1.

[0049] When the current detection signal S1 shows that the current I1 is not greater than the first threshold current Is1, the process proceeds to step S430, maintaining the normal operation of the switching element 26. When the current detection signal S1 shows that the current I1 is greater than the first threshold current Is1, the process proceeds to the judgment step S440.

[0050] In the judgment step S440, it is confirmed whether the current I1 is greater than the second threshold current Is2 based on the current detection signal S1. If the current detection signal S1 shows that the current I1 is greater than the second threshold current Is2, the process proceeds to step S450, and the switching element 26 is permanently turned off. Conversely, if the current detection signal S1 shows that the current I1 is not greater than the second threshold current Is2, the process proceeds to the judgment step S460.

[0051] In step S460, it is confirmed whether the duration for which the current I1 is greater than the first threshold current Is1 exceeds the first preset time td1. If yes, the process proceeds to step S470, periodically turning the switching element 26 off and on. If no, the process proceeds to step S430, maintaining the normal operation of the switching element 26.

[0052] Through the aforementioned process, when the current detection signal S1 shows that the current I1 is greater than the first threshold current Is1 and continues to exceed the first preset time td1, the switching element 26 is periodically turned off and on. In one embodiment, the aforementioned periodic turning off and on of the switching element 26 may involve first turning off the switching element 26, waiting for a second preset time td2, and then turning on the switching element 26.

[0053] The overload warning and protection device 100 and overload warning and protection method provided by this invention can provide a real-time overload warning and protection mechanism for lamp loads. After the power supply 22 supplies power, the control element 140 turns on the switching element 26 to start supplying power to the light-emitting device 24. When the current I1 is greater than the first threshold current Is1 and continues to exceed the first preset time td1, the control element 140 turns off the switching element 26 and waits for a second preset time td2 before turning the switching element 26 on again. At this time, if the current I1 is still greater than the first threshold current Is1, the control element 140 will repeat the above steps and turn off the switching element 26 again. This repeated operation can make the switching element 26 periodically turn off and on, thereby causing the light-emitting device 24 to flash, so as to provide a real-time reminder to the installer or user to pay attention to the overload problem. Furthermore, if the current I1 continues to increase instead of decreasing, and when the current I1 exceeds the second threshold current Is2, the control element 140 will permanently shut off the switching element 26 until the power supply to the overload warning and protection device 100 is turned off and restarted, at which point the switching element 26 can be turned on again to make the light-emitting device 24 light up. In this way, it can be ensured that the light-emitting device 24 will only operate normally when the current falls within its rated range; otherwise, the light-emitting device 24 will flash to remind the user and cut off the power supply for protection when the current I1 is too high.

[0054] The above-described embodiments are merely preferred embodiments provided to fully illustrate the present invention, and the scope of protection of the present invention is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on the present invention are all within the scope of protection of the present invention. The scope of protection of the present invention is defined by the claims.

Claims

1. An overload warning and protection device, applicable to a lighting control system, characterized in that, The lighting control system includes a power supply, a light-emitting device, and a switching element. The power supply supplies power to the light-emitting device via a power supply line, and the switching element is located on the power supply line. The overload warning and protection device includes: A current sensing element is disposed on the power supply line and is adapted to detect the current on the power supply line to generate a current sensing signal; as well as A control element is electrically coupled to the switching element and the current sensing element, and is adapted to receive the current sensing signal and control the conduction state of the switching element according to the current sensing signal. The control element is provided with a first threshold current, a second threshold current and a first preset time, wherein the second threshold current is greater than the first threshold current. Specifically, when the control element detects that the current is greater than the first threshold current and continues for more than the first preset time based on the current detection signal, the control element periodically turns the switching element off and on. When the control element detects that the current is greater than the second threshold current based on the current detection signal, the control element permanently turns off the switching element.

2. The overload warning and protection device as described in claim 1, characterized in that, The light-emitting device is an outdoor light or a Christmas light.

3. The overload warning and protection device as described in claim 1, characterized in that, The control element is a microcontroller.

4. The overload warning and protection device as described in claim 1, characterized in that, The control element has a second preset time, and the control element periodically turns the switching element off and on according to the first preset time and the second preset time.

5. The overload warning and protection device as described in claim 4, characterized in that, The first preset time is equal to the second preset time.

6. The overload warning and protection device as described in claim 4, characterized in that, When the control element detects that the current is greater than the first threshold current and continues to exceed the first preset time based on the current detection signal, the control element turns off the switching element and waits for the second preset time.

7. The overload warning and protection device as described in claim 1, characterized in that, When the control element detects that the current is greater than the second threshold current based on the current detection signal, the control element turns off the switching element and enters a deactivated state.

8. The overload warning and protection device as described in claim 1, characterized in that, The current detection signal is a voltage signal.

9. The overload warning and protection device as described in claim 1, characterized in that, The control element has a first threshold voltage and a second threshold voltage. The first threshold voltage corresponds to the first threshold current, and the second threshold voltage corresponds to the second threshold current. The control element compares the current detection signal with the first threshold voltage to determine whether the current is greater than the first threshold current.

10. The overload warning and protection device as described in claim 1, characterized in that, The control element is equipped with an analog-to-digital converter, which is adapted to convert the current detection signal into a numerical value and determine whether the current is greater than the first threshold current based on the numerical value.

11. An overload warning and protection method, applicable to overload warning and protection devices, characterized in that, The overload warning and protection device is applicable to a lighting control system, which includes a power supply, a light-emitting device, and a switching element. The power supply supplies power to the light-emitting device via a power supply line. The switching element is located on the power supply line. The overload warning and protection device includes a current detection element located on the power supply line, adapted to detect the current on the power supply line to generate a current detection signal. The overload warning and protection method includes: A first threshold current, a second threshold current, and a first preset time are set, wherein the second threshold current is greater than the first threshold current; Receive the current detection signal to detect the current; When the current exceeds the first threshold current and continues for more than the first preset time, the switching element is periodically turned off and on. as well as When the current exceeds the second threshold current, the switching element is permanently turned off.

12. A lighting control system, characterized in that, Include: power supply; A light-emitting device, wherein the power supply is provided to the light-emitting device via a power supply line; A switching element is provided on the power supply line; and An overload warning and protection device, electrically coupled to the switching element, includes: A current sensing element is disposed on the power supply line and is adapted to detect the current on the power supply line to generate a current sensing signal; as well as A control element is electrically coupled to the switching element and the current sensing element, and is adapted to receive the current sensing signal and control the conduction state of the switching element according to the current sensing signal. The control element is provided with a first threshold current, a second threshold current and a first preset time, wherein the second threshold current is greater than the first threshold current. Specifically, when the control element detects that the current is greater than the first threshold current and continues for more than the first preset time based on the current detection signal, the control element periodically turns the switching element off and on. When the control element detects that the current is greater than the second threshold current based on the current detection signal, the control element permanently turns off the switching element.

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