Power-adjustable bath heater protection circuit

Abstract

The utility model relates to a power-adjustable bath heater protection circuit, a power supply input end is provided with a trip coil, a control electrode of a silicon controlled rectifier SCR1 is connected with an electric leakage protection module, and a live wire passes through a zero sequence mutual inductor of the electric leakage protection module and is connected to a bath heater heating lamp. A zero line penetrates through a zero sequence mutual inductor of the electric leakage protection module and is connected to the adjusting module, the adjusting module comprises a power adjusting point locator, a thermistor and a bidirectional silicon controlled rectifier, and a fixed contact at one end of the power adjusting potentiometer is sequentially connected with the thermistor and the other end of the bath heater heating lamp. A fixed contact at the other end of the power regulation potentiometer is connected to the null line through a capacitor C4, a sliding contact of the power regulation potentiometer is connected with a control electrode of the bidirectional silicon controlled rectifier, and a first anode and a second anode of the bidirectional silicon controlled rectifier are connected with the null line and the other end of the bath heater heating bulb respectively; an existing bath heater protection module is simplified, and electric leakage circuit protection of the bath heater heating lamp can be achieved through simple electronic devices.

Description

Technical Field

[0001] The utility model relates to a bathroom heater circuit, in particular to a power-adjustable bathroom heater protection circuit. Background Art

[0002] In the existing circuit of the bathroom heater, when setting the protection circuit, i.e. leakage protection, the control protection circuit structure is complex, and usually a microprocessor and multiple circuits need to be set up to form a protection circuit, such as Chinese patent CN201811129423.8. This not only makes the cost too high, but also makes subsequent maintenance more troublesome. Utility Model Content

[0003] The utility model aims to provide a power-adjustable bathroom heater protection circuit, which solves the problem that the existing bathroom heater protection circuit is relatively complicated.

[0004] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0005] The utility model provides an adjustable power type bathroom heater protection circuit, wherein a trip coil is arranged on the live wire and the neutral wire of the power input end of the circuit, the output end of the trip coil is also connected to the input end of the rectifier bridge, the output end of the rectifier bridge is connected to the control electrode of the thyristor SCR1, the control electrode of the thyristor SCR1 is also connected to a leakage protection module, the live wire passes through the zero-sequence mutual inductor of the leakage protection module and is connected to one end of the bathroom heater heating lamp, the neutral wire passes through the zero-sequence mutual inductor of the leakage protection module and is connected to the adjustment module, the adjustment module includes a power adjustment point positioner, a thermistor and a bidirectional thyristor, the fixed contact at one end of the power adjustment potentiometer is connected to the thermistor and the other end of the bathroom heater heating lamp in sequence, the fixed contact at the other end of the power adjustment potentiometer is connected to the neutral wire, the sliding contact of the power adjustment potentiometer is connected to the control electrode of the bidirectional thyristor, the first anode and the second anode of the bidirectional thyristor are respectively connected to the neutral wire and the other end of the bathroom heater heating bulb.

[0006] Furthermore, a capacitor C5 and a resistor R8 are connected in parallel at both ends of the bidirectional thyristor.

[0007] Furthermore, two ends of the thermistor and the power regulating potentiometer are respectively connected in parallel with a resistor R7 and a resistor R5.

[0008] Furthermore, a bidirectional breakdown diode is arranged between the sliding contact of the power regulating potentiometer and the control electrode of the bidirectional thyristor.

[0009] Furthermore, a discharge resistor and a capacitor C1 are respectively provided between the neutral line and the live line, and the discharge resistor includes a resistor R1 and a resistor R2.

[0010] Due to the application of the above technical solution, the utility model has the following advantages compared with the prior art:

[0011] The utility model discloses an adjustable power bathroom heater protection circuit, which combines the power adjustment circuit and the leakage protection circuit of the bathroom heater heating lamp. The power of the bathroom heater heating lamp can be changed by adjusting the power adjustment potentiometer to the left and right to achieve different usage conditions. At the same time, there is leakage protection during the adjustment process. When leakage occurs, the tripping coil automatically trips to disconnect the use of the bathroom heater heating lamp. The existing bathroom heater protection module is simplified, and the leakage circuit protection of the bathroom heater heating lamp can be achieved with simple electronic devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Hereinafter, some specific embodiments of the present invention will be described in detail in an exemplary and non-limiting manner with reference to the accompanying drawings. The same reference numerals in the accompanying drawings indicate the same or similar components or parts. It should be understood by those skilled in the art that these drawings are not necessarily drawn to scale. In the accompanying drawings:

[0013] Figure 1 It is a circuit diagram of an embodiment of the utility model;

[0014] Figure 2 It is a circuit diagram of the regulating module of the utility model.

[0015] The reference numerals are described as follows:

[0016] 1. Trip coil; 2. Rectifier bridge; 3. Zero-sequence transformer; 4. Bathroom heating lamp; 5. Power adjustment point positioner; 6. Thermistor; 7. Bidirectional thyristor; 8. Bidirectional breakdown diode. DETAILED DESCRIPTION

[0017] The technical solution of the utility model will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0018] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0019] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0020] like Figure 1 As shown, it includes a power input terminal, a regulation module and a leakage protection module.

[0021] A trip coil 1 is arranged on the live wire and the neutral wire of the power input end of the circuit, the output end of the trip coil 1 is also connected to the input end of the rectifier bridge 2, the output end of the rectifier bridge 2 is connected to the control electrode of the thyristor SCR1, and the output end of the trip coil 1 is connected to the input end of the rectifier bridge 2; the rectifier bridge 2 is used to control the action power supply of the trip coil 1, and the leakage protection module is also connected to the control electrode of the thyristor SCR1. Under normal conditions, the trip coil 1 works normally and the power supply supplies the load normally. When leakage occurs, the leakage protection module will quickly feedback to the control electrode of the thyristor SCR1 to turn it on, and the thyristor SCR1 and the side where the rectifier bridge 2 are located are turned on, so that the trip coil 1 is tripped and disconnected, so that the power supply no longer supplies power to the load.

[0022] The live wire passes through the zero-sequence transformer 3 of the leakage protection module and is connected to one end of the bathroom heater 4, and the neutral wire passes through the zero-sequence transformer 3 of the leakage protection module and is connected to the adjustment module. Figure 2 As shown, the regulating module includes a power regulating potentiometer 5, a thermistor 6 and a bidirectional thyristor 7. The fixed contact of the right-hand end of the power regulating potentiometer is connected to the thermistor 6 and the other end of the bathroom heater heating lamp 4 in sequence. The fixed contact of the left-hand end of the power regulating potentiometer 5 is connected to the neutral line. The sliding contact of the power regulating potentiometer is connected to the control electrode of the bidirectional thyristor 7. The first anode and the second anode of the bidirectional thyristor 7 are respectively connected to the neutral line and the other end of the bathroom heater heating lamp 4. A bidirectional breakdown diode 8 is arranged between the sliding contact of the power regulating potentiometer and the control electrode of the bidirectional thyristor 7. The bidirectional breakdown diode 8 can also be used to suppress instantaneous overvoltage.

[0023] After the circuit is turned on, the resistor R6, thermistor 6 and power regulating positioner 5 are connected in series and charged to capacitor C4. When the charging voltage of capacitor C4 is higher than the breakdown voltage of bidirectional breakdown diode 8, bidirectional breakdown diode 8 will be broken down, thereby transferring current to the control electrode of bidirectional thyristor 7, making the bidirectional thyristor 7 diode turned on, that is, by adjusting the resistance of the power regulating positioner 5, the charging speed of capacitor C4 is changed, and then the conduction angle of bidirectional thyristor 7 can be changed, thereby changing the current (average value) passing through the bathroom heater heating lamp 4 to achieve continuous temperature control. When the power regulating positioner 5 is adjusted to the left-hand end, the resistance of the power regulating positioner 5 increases, the charging speed decreases, and the circuit passing through the bathroom heater heating lamp 4 is reduced, so that the power is reduced. When the power regulating positioner 5 is adjusted to the right-hand end, the resistance of the power regulating positioner 5 decreases, the charging speed increases, and the circuit passing through the bathroom heater heating lamp 4 is increased, so that the power of the heating lamp is increased.

[0024] The purpose of the thermistor 6 is that when the voltage of the power plug increases, the power of the bathroom heater lamp 4 increases and the temperature of the power regulating thyristor SCR1 body is increased. When the thermistor 6 detects that the temperature of the thyristor SCR1 has increased, its thermistor 6 will automatically increase. The increase in resistance will cause the charging current of the capacitor C4 to decrease, so that the charging speed of the capacitor will be reduced, and the current of the bathroom heater lamp 4 will be reduced accordingly, which will reduce the power of the bathroom heater and then reduce the temperature.

[0025] The two ends of the bidirectional thyristor 7 are also connected in parallel with a capacitor C5 and a resistor R8 to form an RC filter circuit for eliminating EMI interference filtering.

[0026] The two ends of the thermistor 6 and the power adjustment potentiometer are respectively connected in parallel with a resistor R7 and a resistor R5. The resistor R7 is used to set the upper limit of automatic power compensation when the temperature of the SCR1 body is at the highest state, and the resistor R5 is used to set the lower limit of minimum power.

[0027] A bleeder resistor and capacitor C1 are respectively arranged between the neutral line and the live line. The bleeder resistor includes resistor R1 and resistor R2. Capacitor C1 is a safety capacitor connected at both ends of the input line to eliminate differential mode interference. The function of the bleeder resistor is to instantly release the terminal voltage between C4 after unplugging the power plug to prevent human body from touching the plug and getting an electric shock.

[0028] Since the live wire and the neutral wire are connected to the regulating module after passing through the zero-sequence transformer 3 of the leakage protection module, if leakage occurs in the regulating module, the zero-sequence transformer 3 triggers the control electrode of the thyristor SCR1 to turn on and transmit information to the tripping coil 1, causing it to trip and disconnect when it senses that the sum of the currents of the live wire and the neutral wire is not zero.

[0029] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with this technology to understand the content of the present invention and implement it accordingly. They cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A power-adjustable bathroom heater protection circuit, characterized in that: A trip coil is arranged on the live wire and the neutral wire of the power input end of the circuit, the output end of the trip coil is connected to the input end of the rectifier bridge, the output end of the rectifier bridge is connected to the control electrode of the thyristor SCR1, the control electrode of the thyristor SCR1 is also connected to the leakage protection module, the live wire passes through the zero-sequence mutual inductor of the leakage protection module and is connected to one end of the bathroom heater heating lamp, the neutral wire passes through the zero-sequence mutual inductor of the leakage protection module and is connected to the adjustment module, the adjustment module includes a power adjustment potentiometer, a thermistor and a bidirectional thyristor, the fixed contact at one end of the power adjustment potentiometer is connected to the thermistor and the other end of the bathroom heater heating lamp in sequence, the fixed contact at the other end of the power adjustment potentiometer is connected to the neutral wire through capacitor C4, the sliding contact of the power adjustment potentiometer is connected to the control electrode of the bidirectional thyristor, the first anode and the second anode of the bidirectional thyristor are respectively connected to the neutral wire and the other end of the bathroom heater heating bulb.

2. According to claim 1, a power-adjustable bathroom heater protection circuit, wherein: The two ends of the bidirectional thyristor are also connected in parallel with a capacitor C5 and a resistor R8.

3. According to the adjustable power type bathroom heater protection circuit of claim 1, wherein: The two ends of the thermistor and the power regulating potentiometer are respectively connected in parallel with a resistor R7 and a resistor R5.

4. According to the adjustable power type bathroom heater protection circuit of claim 1, wherein: A bidirectional breakdown diode is arranged between the sliding contact of the power regulating potentiometer and the control electrode of the bidirectional thyristor.

5. According to the adjustable power type bathroom heater protection circuit of claim 1, wherein: A discharge resistor and a capacitor C1 are respectively arranged between the neutral line and the live line, and the discharge resistor includes a resistor R1 and a resistor R2.

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