JP5394433B2 - Electrical equipment with a resistor that suppresses inrush current - Google Patents

Description

The present invention relates to an electrical device. In particular, the present invention relates to an electric device including a resistor that suppresses inrush current.
Here, the electric device broadly means devices that require electricity for the operation, and is not limited to devices that operate only by electricity. For example, even a so-called gas device that burns a gaseous fuel such as city gas requires electricity for its operation to be included in the electric device here.

  Patent Documents 1 and 2 disclose circuit structures that suppress inrush current of electronic devices. The inrush current is a large current that flows into an uncharged smoothing circuit (capacitor) when the power is turned on. In these circuit structures, a resistor, such as a resistance element or a power thermistor, is provided between the AC power supply and the smoothing circuit, thereby suppressing inrush current flowing into the uncharged smoothing circuit. .

  The above-described resistor is necessary only when the power is turned on, and in the subsequent stage where the electric device operates, power loss is generated. Therefore, a configuration is adopted in which an electromagnetic relay is provided in parallel with the resistor, and the resistor can be bypassed by exciting the electromagnetic relay and closing the contact.

JP-A-1-274665 JP 2000-92695 A

  In order to keep the contact of the electromagnetic relay closed after the power is turned on, it is necessary to continue energizing the exciting current to the coil of the electromagnetic relay. Therefore, there arises a problem that standby power of the electric equipment increases. To solve this problem, a method of opening the electromagnetic relay in the standby state and exciting the electromagnetic relay only when the electric device is in operation can be considered. However, the opening and closing of the electromagnetic relay is frequently repeated according to the operation / stop of the electric device, and a new problem arises that the life of the relay contact is exhausted early.

  The present invention solves the above problems. The present invention provides a technique capable of extending the life of a relay contact while suppressing standby power in an electrical device including a resistor that suppresses an inrush current and an electromagnetic relay that bypasses the resistor.

  An electrical device embodied by the present invention includes a rectifier circuit, a smoothing circuit, a plurality of electrical loads, and control means. The rectifier circuit is a circuit that rectifies power from an AC power supply. The smoothing circuit is provided on the output side of the rectifier circuit and is a circuit that smoothes the rectified power. The plurality of electrical loads are, for example, sensors, motors, electromagnetic valves, etc., are provided on the output side of the smoothing circuit, and are driven by the smoothed power. The control circuit realizes at least the first operation state and the second operation state by selectively operating those electric loads.

  The electric device further includes a resistor that suppresses the inrush current and an electromagnetic relay that bypasses the resistor. The resistor is provided between the AC power supply and the smoothing circuit, and suppresses an inrush current that flows into the smoothing circuit when the power is turned on. The electromagnetic relay is provided in parallel with the resistor. The electromagnetic relay is a normally open type, and when energized, the contact can be closed and both ends of the resistor can be short-circuited.

  In the above-described electrical device, the power consumption of the electrical load that operates in the second operation state is greater than the power consumption of the electrical load that operates in the first operation state. Therefore, the electromagnetic relay is configured not to be excited when the first operation state is started but to be excited when the second operation state is started. That is, in the first operating state, the power consumption due to the electrical load is small, so the value of the current flowing through the resistor is also small. In this case, since the power loss due to the resistor is relatively small, the electromagnetic relay is not opened or closed. As a result, the number of times the electromagnetic relay is opened and closed is reduced, and the life of the relay contact is extended. On the other hand, in the second operating state, the power consumption by the electrical load is large, so the value of the current flowing through the resistor is also large. In this case, since the power loss due to the resistor is relatively large, the electromagnetic relay is closed to bypass the resistor, and the power loss due to the resistor is avoided.

  Furthermore, once energized, the electromagnetic relay is configured to continue to be excited as long as either the first operating state or the second operating state continues. That is, once the relay contact is closed, even if the second operation state changes to the first operation state, the electromagnetic relay continues to be excited to avoid power loss due to the resistor. Compared with the method in which the relay contact is opened each time the second operating state is completed, more power loss due to the resistor can be avoided without increasing the number of times the relay contact is opened and closed. Ultimately, excitation of the electromagnetic relay may be stopped when all the operating states are finished and the standby state is reached. Thereby, standby power can also be reduced.

  In the electric device described above, the first operation state and the second operation state can be determined according to the value of the current flowing through the resistor with the electromagnetic relay opened or an index corresponding thereto. That is, for a plurality of operating states that can be carried out by the electric device, values of currents flowing through the resistors with the electromagnetic relay opened are obtained. Then, the operating state in which the current value is smaller than the predetermined threshold can be set as the first operating state, and the operating state in which the current value is larger than the threshold can be set as the second operating state. At this time, instead of the value of the current flowing through the resistor, another index corresponding thereto, such as the amount of heat generated by the resistor or the power consumption of the electrical load, may be used.

  The above-described configuration of the electric device can be applied to various electric devices. As an example, the above-described electrical device can be a device that can perform at least two of a hot water supply operation, a heating operation, and a bath operation (a so-called hot water supply device, a hot water supply heating device, a bath tub device, and the like). Here, the hot water supply operation means an operation of boiling hot water supplied to a hot water supply location. The heating operation means an operation for heating by circulating the heat medium of the heating terminal. Bath operation means an operation in which hot water in a bathtub is circulated and heated. In this case, each of the first operation state and the second operation state can be a state in which at least one of a hot water supply operation, a heating operation, and a bath operation is performed.

  In the electrical equipment described above, the electromagnetic relay is opened and closed according to the operating state of the electrical equipment. This is based on the fact that the current value of the resistor can be predicted to some extent according to the operating state of the electrical equipment. On the other hand, it is also effective to actually measure the current value of the resistor or the index corresponding thereto and to excite the electromagnetic relay according to the measured value. In this case, it is not necessary to determine the operating state performed by the electrical device or to determine whether the electromagnetic relay needs to be excited for each operating state. And after an electromagnetic relay is once excited, it is preferable to continue excitation of an electromagnetic relay until the driving | operation of an electric equipment is complete | finished irrespective of a measured value. This method can also improve the standby power of the electric device, the power loss due to the resistor, and the life of the relay contact.

  Based on the above knowledge, the following electrical devices can be realized. This electrical device is provided on the output side of the rectifier circuit that rectifies the power from the AC power source and the rectifier circuit, and is provided on the output side of the smoothing circuit that smoothes the rectified power. A plurality of electrical loads driven by the smoothed power, a control means for realizing at least one operating state by selectively operating the plurality of electrical loads, and between the AC power source and the smoothing circuit. A resistor that suppresses inrush current to the smoothing circuit, an electromagnetic relay that is provided in parallel to the resistor and bypasses the resistor when excited, and flows through the resistor Detection means for detecting a current value or an index corresponding to the current value is provided. The electromagnetic relay is excited when the detection value by the detection means becomes a predetermined value or more, and once excited, the electromagnetic relay is continuously excited as long as the operation state by the control means continues. Although this electronic device is also an example, it can be a device capable of performing at least two of a hot water supply operation, a heating operation, and a bath operation.

  ADVANTAGE OF THE INVENTION According to this invention, in the electric equipment provided with the resistor which suppresses inrush current, and the electromagnetic relay which bypasses the resistor, the lifetime of a relay contact can be extended, suppressing standby electric power.

The block diagram which shows the functional structure of the hot-water supply heating apparatus of an Example. The circuit diagram which shows the electrical structure of the hot-water supply heating apparatus of an Example. The table | surface which shows the list | wrist of the main electric loads which a hot-water supply heater has, and the electric load which operate | moves at the time of various driving | operation. The table which shows the electric current value (calculated value) which flows into a thermistor, the heat_generation | fever value (actual value) of a thermistor, and the open / close state of a relay contact for every operation state of a hot-water heater. Here, “OFF” indicates a state where the excitation coil is not energized and the relay contact is opened, and “ON” indicates a state where the excitation coil is energized and the relay contact is closed. The time chart which shows AC current (A) which flows into a thermistor, the opening / closing state (B) of a relay contact, the presence or absence (C) of hot water supply operation, and the presence or absence (D) of heating operation. FIG. 3 is a modification of the circuit diagram shown in FIG. 2 with a current transformer or the like for measuring the AC current flowing through the thermistor added.

  In carrying out the present invention, the rectifier circuit may be a half-wave rectifier circuit or a full-wave rectifier circuit. The rectifier circuit may be a diode bridge, for example, but is not particularly limited.

  In carrying out the present invention, the smoothing circuit may be a capacitor (capacitor), but is not particularly limited. The configuration of the smoothing circuit is not particularly limited as long as it can smooth the rectified power including ripples and has a characteristic that an inrush current flows when the power is turned on.

  In practicing the present invention, a resistor and a thermistor (including a power thermistor) can be employed as the resistor for suppressing the inrush current, although it is only an example. In this case, the thermistor is preferably an NTC type in which the resistance value decreases as the temperature rises. When power loss occurs in the thermistor, the resistance value decreases as the temperature rises, so that further power loss can be suppressed.

  In carrying out the present invention, the electric device can be a hot water heater. In this case, the hot water heater can perform hot water operation to boil hot water supplied to the hot water supply location, heating operation to circulate and heat the heating medium of the heating terminal, and bath operation to circulate and heat the hot water in the bathtub It is preferable that

  In the hot water supply and heating apparatus described above, generally, when performing at least two of the hot water supply operation, the heating operation, and the bath operation at the same time, rather than performing one of the hot water supply operation, the heating operation, and the bath operation alone, Electrical power consumption due to load tends to increase. Therefore, in one embodiment of the present invention, the first operation state is a state in which one of the hot water supply operation, the heating operation, and the bath operation is performed alone, and the second operation state is the hot water supply operation and heating. It may be in a state in which at least two of driving and bathing are performed simultaneously. In this configuration, for example, even if the hot water supply operation is performed alone, the electromagnetic relay is not excited. However, for example, when a hot water supply operation and a heating operation are performed simultaneously, the electromagnetic relay is excited. Once the electromagnetic relay is excited, the excitation of the electromagnetic relay is continued if the heating operation is continued even after the hot water supply operation is finished. Thereafter, when the heating operation is completed and the state returns to the standby state, the excitation of the electromagnetic relay is stopped.

  Depending on the specific structure of the hot water supply and heating device, the power consumption may vary greatly between the hot water supply operation, the heating operation, and the bath operation. Therefore, among the hot water supply operation, heating operation, and bath operation, it may be preferable to excite the electromagnetic relay by treating it as the second operation state described above even when it is carried out independently. . Alternatively, among the hot water supply operation, the heating operation, and the bath operation, it is preferable that two relatively small power consumptions are handled as the above-described first operation state and the electromagnetic relay is de-energized even when it is performed simultaneously. There is also. These are not limited to the hot water heater / heater, and similarly apply to various operations of various electrical devices.

  In general, the hot water supply operation is characterized in that it consumes relatively less power than the heating operation and bath operation, but is very frequently repeated. Therefore, the state in which the hot water supply operation is performed alone can be the first operation state described above. According to this structure, the frequency | count of opening and closing of an electromagnetic relay can be reduced significantly, and the lifetime of a relay contact can be extended significantly. At this time, the power loss due to the resistor can be kept relatively small.

  It is preferable that the above-described hot water heater / heater includes a gas heat source device that burns gaseous fuel or liquid fuel to heat the hot water or the heat medium. In this case, a blower fan, a hot water pump, a solenoid valve, a temperature sensor, a flow sensor, and the like provided in the gas heat source device correspond to the plurality of electric loads described above. By selectively operating part or all of these electrical loads, various operations such as a hot water supply operation, a heating operation, and a bath operation are performed independently or simultaneously.

  The hot water supply / room heating device 10 according to the embodiment will be described with reference to the drawings. The hot water heater 10 is an example of an electric device that requires electricity for its operation. As shown in FIG. 1, the hot water supply and heating apparatus 10 mainly includes a hot water supply and heating unit 20, a heating terminal 30, and a remote controller 50. A water supply pipe 12 that supplies clean water and a hot water supply pipe 14 that discharges hot water are connected to the hot water supply and heating unit 20.

  The hot water supply / heating unit 20 is a gas heat source that burns gaseous fuel such as city gas, and can heat the water supplied through the water supply pipe 12. The heated hot water is supplied through a hot water supply pipe 14 to a hot water supply location such as a currant. Alternatively, the heated hot water is supplied to the bathtub 40 through the bath return pipe 44. That is, the bathtub 40 is one of hot water supply points. In this way, the hot water supply / room heating device 10 can perform the “hot water supply operation” in which the hot water supplied to the hot water supply location is boiled.

  The hot water supply / heating unit 20 is also a gas heat source device that circulates and heats the heat medium of the heating terminal 30. Although it is an example, the heating terminal 30 includes floor heating, a panel heater, a bathroom heating dryer, and the like. Moreover, although the heat medium of the heating terminal 30 is an example, it is warm water or antifreeze. The hot water supply / heating unit 20 is connected to the heating terminal 30 via a heating feed pipe 32 and a heating return pipe 34. The heat medium of the heating terminal 30 is sent to the hot water supply / heating unit 20 through the heating feed pipe 32. The heat medium is heated in the hot water supply / heating unit 20 and returned to the heating terminal 30 through the heating return pipe 34. The circulation of the heat medium is performed by a heating pump (not shown) of the hot water supply / heating unit 20. Thus, the hot water supply / room heating device 10 can perform the “heating operation” in which the heating medium of the heating terminal 30 is circulated and heated. In the present embodiment, only one heating terminal 30 is shown, but a plurality of heating terminals 30 such as floor heating, panel heaters, and bathroom heating / drying units are connected to the hot water supply / heating unit 20 in a plurality of systems. You can also

  The hot water supply and heating unit 20 is also a gas heat source device that circulates the hot water in the bathtub 40 and heats (cooks it). The hot water supply / heating unit 20 is connected to the bathtub 40 via a bath feed pipe 42 and a bath return pipe 44. The hot water in the bathtub 40 is sent to the hot water supply / heating unit 20 through the bath feed pipe 42, heated in the hot water supply / heating unit 20, and then returned to the bathtub 40 through the bath return pipe 44. The hot water is circulated by a bath pump (not shown) of the hot water supply / heating unit 20. In this manner, the hot water supply / room heating device 10 can perform “bath operation” in which the hot water in the bathtub 40 is circulated and heated. Note that in the hot water heater 10, the path for heating the hot water in the bath operation is provided independently of the path for heating the hot water in the hot water operation in consideration of hygiene.

  Next, with reference to FIG. 2, the circuit structure of the hot water heater 10 will be described. As shown in FIG. 2, the hot water supply / room heating device 10 is operated by an external AC power supply (commercial power supply) 100. As shown in FIG. 2, the hot water supply / room heating device 10 includes a leakage breaker 102, a filter 104, a rectifier circuit 108, and a smoothing capacitor 110. The earth leakage breaker 102 is a circuit breaker that is opened when an overcurrent is detected. The filter 104 is a circuit for removing noise such as a surge voltage, and includes a choke coil and a capacitor. The rectifier circuit 108 is a circuit that rectifies power from the AC power supply 100. The rectifier circuit 108 of this embodiment is a full-wave rectifier circuit, specifically a diode bridge. The smoothing capacitor 110 is a circuit that is provided on the output side of the rectifier circuit 108 and smoothes the electric power after rectification by the rectifier circuit 108.

  The hot water heater 10 includes a controller 114 and a plurality of loads 116 in order to perform the various operations described above. As shown in FIG. 3, the plurality of loads 116 are electrical such as sensors, motors, and electromagnetic valves. The plurality of loads 116 are provided on the output side of the smoothing capacitor 110 via the switching power supply 112, and are driven by the power smoothed by the smoothing capacitor 110. The controller 114 is a control unit that realizes an operation state in which the above-described hot water supply operation, heating operation, and bath operation are performed independently or simultaneously by selectively operating a plurality of loads 116. As shown in FIG. 3, the load 116 to be operated varies depending on the operation to be performed. The controller 114 is also provided on the output side of the smoothing capacitor 110 via the switching power supply 112.

  When the hot water heater 10 is connected to the AC power source 100 and the hot water heater 10 is turned on, the rectified and smoothed power is supplied to the controller 114 via the switching power source 112. The controller 114 is configured using a computer, and is activated upon receiving power supply. That is, the hot water supply / room heating device 10 is in a standby state. Thereafter, when the user opens the currant, the hot water supply / room heating device 10 performs a hot water supply operation. The controller 114 selectively operates the load 116 necessary for the hot water supply operation (see FIG. 3). Alternatively, in response to an operation on the remote controller 50 by the user, the hot water heater / heater 10 performs a heating operation or a bath operation. Also at this time, the controller 114 selectively operates the necessary load 116 (see FIG. 3).

  Here, when the power is turned on, an inrush current flows into the smoothing capacitor 110. Therefore, a power thermistor 106 that suppresses an inrush current is provided between the AC power supply 100 and the smoothing capacitor 110. Further, in order to avoid power loss due to the power thermistor 106 after the power is turned on, the electromagnetic relay 120 is provided in parallel to the power thermistor 106. The electromagnetic relay 120 has a relay contact 122 and an exciting coil 124. The electromagnetic relay 120 is a normally open contact relay, and is configured such that the relay contact 122 is closed while the exciting coil 124 is energized. The exciting coil 124 is connected to the switching power supply 112 via the semiconductor switch 126. The semiconductor switch 126 is turned on / off by the controller 114. That is, excitation / non-excitation of the exciting coil 124, that is, opening / closing of the relay contact 122 is controlled by the controller 114.

  After power-on, if the electromagnetic relay 120 is closed, the power thermistor 106 can be bypassed, and power loss due to the power thermistor 106 can be suppressed. However, in this case, since the current is continuously supplied to the exciting coil 124, standby power of the hot water supply / room heating device 10 is increased. In order to solve this problem, it is conceivable that the electromagnetic relay 120 is opened in the standby state and the electromagnetic relay 120 is excited in accordance with various operations of the hot water supply / room heating device 10. However, in such a method, the electromagnetic relay 120 is frequently opened and closed in accordance with the operation / stop of the hot water supply / room heating device 10, and a new problem arises that the life of the relay contact 122 is exhausted early. .

  Therefore, in the hot water supply and heating apparatus 10 of the present embodiment, the electromagnetic relay 120 is selectively opened and closed according to the operating state. That is, the electromagnetic relay 120 is opened and closed in some operating states, but the electromagnetic relay 120 is not opened and closed in some operating states. FIG. 4 shows the relationship. As shown in FIG. 4, the value of the current flowing through the power thermistor 106 and the amount of heat generated vary according to the operating state of the hot water supply / room heating device 10 (the electromagnetic relay 120 is in an open state). This means that the power loss due to the power thermistor 106 also changes according to the operating state. Therefore, in this embodiment, a threshold is set for the current value flowing through the power thermistor 106, and the electromagnetic relay 120 is not energized and the relay contact 122 is opened in an operating state where the current value flowing through the power thermistor 106 is smaller than the threshold. Keep it off (OFF in the figure). In other words, in an operation state in which the power loss due to the power thermistor 106 is relatively small, the electromagnetic relay 120 is not opened and closed to reduce the burden on the relay contact 122. As an example, the threshold current described above is set to 2 amperes. Therefore, when the hot water supply operation or the heating operation is performed alone, the electromagnetic relay 120 is not excited and the relay contact 122 is kept open.

  On the other hand, among the operating states that can be implemented by the hot water heater 10, when the value of the current flowing through the power thermistor 106 is larger than the above threshold, the electromagnetic relay 120 is excited at the start and the relay contact 122 is closed. (In the figure, it is ON). In the present embodiment, as an example, the value of the current flowing through the power thermistor 106 is a threshold value in a state where at least two of the hot water supply operation, the heating operation, and the bath operation are performed at the same time, and in a state where the bath operation is performed independently. Greater than the current (2 amps). In such an operating state, the power loss in the power thermistor 106 is relatively large. Therefore, power loss due to the power thermistor 106 is avoided by closing the relay contact 122 of the electromagnetic relay 120 and bypassing the power thermistor 106. This is based on the determination that the power loss due to the power thermistor 106 is sufficiently larger than the cost associated with opening and closing the electromagnetic relay 120. Here, the cost associated with the opening and closing of the electromagnetic relay 120 takes into account not only the power supplied to the exciting coil 124 but also the component costs of the electromagnetic relay 120 whose life expectancy decreases with the opening and closing.

  Once the electromagnetic relay 120 is energized, the controller 114 is configured to continue exciting the electromagnetic relay 120 as long as any one of the hot water supply operation, the heating operation, and the bath operation is performed. For example, it is assumed that the hot water supply operation is further performed during the heating operation. At this time, the controller 114 excites the electromagnetic relay 120 and bypasses the power thermistor 106. Thereafter, it is assumed that the hot water supply operation is finished and the heating operation is again performed alone. In this case, the controller 114 of this embodiment continues to excite the electromagnetic relay 120 and continues to bypass the power thermistor 106. According to this method, compared with the case where the electromagnetic relay 120 is opened at the time when the hot water supply operation is completed (that is, when the simultaneous operation is completed), the power by the power thermistor 106 is not increased. More losses can be avoided.

  An operation example of the hot water supply / room heating device 10 will be described with reference to the time chart of FIG. 5. Time T1 in FIG. 5 indicates a point in time when the hot water supply / room heating device 10 is connected to the AC power supply 100 and the hot water supply / room heating device 10 is turned on. At this time, the relay contact 122 is open, and the inrush current to the smoothing capacitor 110 is suppressed by the power thermistor 106. Thereafter, it is assumed that a hot water supply operation is performed at times T2 and T3. Further, it is assumed that the heating operation is started at time T4. As described above, the relay contact 122 is not closed even if the hot water supply operation or the heating operation is performed alone.

  However, it is assumed that the hot water supply operation is further performed at time T5 during the heating operation. In this case, the relay contact 122 is closed along with the simultaneous operation of the hot water supply operation and the heating operation. Once the electromagnetic relay 120 is closed, the electromagnetic relay 120 is kept closed until time T7 when the heating operation ends, regardless of whether or not the hot water supply operation is performed. Therefore, even when the hot water supply operation is repeated during the heating operation (time T5, T6), the electromagnetic relay 120 is not repeatedly opened and closed. Thereafter, even when the hot water supply operation is again performed alone at time T8, the electromagnetic relay 120 is not closed. Although not shown in FIG. 5, when the bath operation is performed, the electromagnetic relay 120 is closed even if it is a single operation. Thereafter, when all the operations are completed, the electromagnetic relay 120 is opened.

  In the hot water supply and heating apparatus 10 of the present embodiment, the electromagnetic relay 120 is selectively opened and closed according to the operating state, so that the number of times the electromagnetic relay 120 is opened and closed can be significantly reduced. In particular, the hot water supply operation is characterized in that it consumes less power than the heating operation and bath operation, but is very frequently repeated. Therefore, it is preferable not to open and close the electromagnetic relay 120 for such a hot water supply operation, whereby the life of the relay contact 122 can be greatly extended. However, the operation state shown in FIG. 4 and the relationship of opening and closing the relay contact 122 are merely examples, and are not particularly limited. The opening and closing of the relay contact 122 may be appropriately determined in consideration of the planned power consumption of the load 116 in each operating state (that is, the current value that can flow through the power thermistor 106). At this time, it is also effective to consider the frequency of each operation state together. As a result, the standby power of the hot water heater / heater 10, the power loss due to the power thermistor 106, and the life of the relay contact 122 can be improved.

  In the present embodiment, the value of the current flowing through the power thermistor 106 is obtained for each of a plurality of operating states that the hot water supply / room heating device 10 can implement. This may be a calculated value or an actually measured value. And about the driving | running state in which the said current value becomes smaller than a threshold current, it is set as the driving | running state (1st driving | running state) which does not excite the electromagnetic relay 120, and about the driving | running state where the said current value becomes larger than a threshold current 120 is an operation state in which 120 is excited (second operation state). Such a distinction is not limited to the value of the current flowing through the power thermistor 106, and can be performed using another index corresponding thereto. For example, the power consumption by the load 116 is one of indices corresponding to the value of the current flowing through the power thermistor 106. Therefore, the power consumption of the load 116 is obtained for each operation state, and the power consumption that is smaller than the predetermined threshold power is set to the operation state (first operation state) in which the electromagnetic relay 120 is not excited. For the case where the electric power is larger than the threshold power, the operation state (second operation state) in which the electromagnetic relay 120 is excited can be set.

  Alternatively, as shown in FIG. 4, the heat generation amount (temperature rise width) of the power thermistor 106 is also one of the indexes corresponding to the value of the current flowing through the power thermistor 106. Accordingly, the heat generation amount of the power thermistor 106 is obtained for each operation state, and the operation state in which the electromagnetic relay 120 is not excited (the first operation state) when the heat generation amount is smaller than a predetermined threshold heat generation amount. In the case where the heat generation amount is larger than the threshold heat generation amount, the operation state (second operation state) in which the electromagnetic relay 120 is excited can be used.

  In contrast to the above, it is also effective to open and close the electromagnetic relay 120 according to the measured value while actually measuring the current value of the power thermistor 106 or the index corresponding thereto. FIG. 6 shows an example of the circuit configuration in that case. As shown in FIG. 6, the current value of the power thermistor 106 can be measured by a current transformer 130 and a sensor amplifier 132. An output signal of the sensor amplifier 132 is input to the controller 114. Thereby, the controller 114 can control the electromagnetic relay 120 according to the current value of the power thermistor 106. As an example, the controller 114 is programmed to excite the electromagnetic relay 120 when the current value of the power thermistor 106 becomes 2 amperes or more. In this case, as a result, the electromagnetic relay 120 is excited according to the operating state, as in the relationship shown in FIG. After the electromagnetic relay 120 is once excited, the excitation of the electromagnetic relay 120 is continued until all of the hot water supply operation, the heating operation, and the bath operation are completed regardless of the measurement value input from the sensor amplifier 132. Is preferred. Thereby, the standby power of the hot water heater 10, the power loss due to the power thermistor 106, and the life of the relay contact 122 can be improved. Here, the threshold value of 2 amperes can be changed as appropriate according to the configuration of the apparatus.

  As mentioned above, although the Example of this invention was described in detail, these are only illustrations and do not limit a claim. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.

  The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or the drawings can achieve a plurality of objects at the same time, and achieving one of the objects itself has technical utility.

DESCRIPTION OF SYMBOLS 10: Hot-water supply heating apparatus 12: Water supply pipe 14: Hot-water supply pipe 20: Hot-water supply heating unit 30: Heating terminal 32: Heating feed pipe 34: Heating return pipe 40: Bathtub 42: Bath feed pipe 44: Bath return pipe 50: Remote control 100: AC power supply 102: Earth leakage breaker 104: Filter 106: Power thermistor 108: Rectifier circuit 110: Smoothing capacitor 112: Switching power supply 114: Controller 116: Load 120: Electromagnetic relay 122: Relay contact 124: Excitation coil 126: Semiconductor switch 130: Current Transformer 132: sensor amplifier

Claims (4)

A rectifier circuit for rectifying the power from the AC power supply;
A smoothing circuit that is provided on the output side of the rectifier circuit and smoothes the power after rectification;
A plurality of electrical loads provided on the output side of the smoothing circuit and driven by the smoothed power;
The smoothing circuit is provided between the AC power supply and the smoothing circuit, by controlling the plurality of electrical loads selectively to realize at least the first operating state and the second operating state, the AC power source, and the smoothing circuit. A resistor that suppresses the inrush current to
Provided in parallel with the resistor, comprising an electromagnetic relay that bypasses the resistor when excited,
The power consumption of the electrical load operating in the second operating state is greater than the power consumption of the electrical load operating in the first operating state,
The electromagnetic relay is not excited when the first operation state is started, is excited when the second operation state is started, and once energized, either the first operation state or the second operation state is detected. An electric device characterized by being excited as long as it continues. The first operation state is an operation state in which a value of a current flowing through the resistor or an index corresponding to the current value when the electromagnetic relay is opened is smaller than a predetermined threshold value.
2. The second operation state is an operation state in which a value of a current flowing through the resistor or an index corresponding to the current value when the electromagnetic relay is opened is larger than the threshold value. Electrical equipment. The electrical device performs at least two of a hot water supply operation for boiling hot water supplied to a hot water supply location, a heating operation for heating by circulating a heating medium of a heating terminal, and a bath operation for heating by circulating hot water in a bathtub. Possible equipment,
The electric device according to claim 1, wherein each of the first operation state and the second operation state is a state in which at least one of a hot water supply operation, a heating operation, and a bath operation is performed. A rectifier circuit for rectifying the power from the AC power supply;
A smoothing circuit that is provided on the output side of the rectifier circuit and smoothes the power after rectification;
A plurality of electrical loads provided on the output side of the smoothing circuit and driven by the smoothed power;
Control means for realizing at least one operating state by selectively operating the plurality of electrical loads;
A resistor that is provided between the AC power source and the smoothing circuit and suppresses an inrush current to the smoothing circuit;
An electromagnetic relay that is provided in parallel to the resistor and bypasses the resistor when excited;
A measuring means for measuring a current value flowing through the resistor or an index corresponding thereto;
The electromagnetic relay is energized when a measured value by the measuring unit becomes a predetermined value or more, and once energized, the electromagnetic relay is energized as long as the operation state by the control unit continues. machine.

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