JP2005283375A - Leak detection device and bathroom air conditioner provided therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the erroneous detection of leak due to a noise without providing a hardware such as a noise filter. <P>SOLUTION: A ZCT coil (zero-phase current transformer) 47 as a leak signal generation means for generating a leak signal when the leak occurs and a determining means 48A for determining whether the leak signal transmitted from the ZCT coil (zero-phase current transformer) 47 is a noise are provided on a leak detection device 40 for detecting the leak. Particularly, a noise filter is not provided as the hardware for removing the noise contained in the leak signal transmitted from the ZCT coil (zero-phase current transformer) 47. It is determined on software whether the leak signal transmitted from the ZCT coil (zero-phase current transformer) 47 is the noise, and it is determined that the leak occurs actually when it is determined that the leak signal is not the noise. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a leakage detection device for detecting leakage and a bathroom air conditioner including the leakage detection device, and in particular, it is possible to reduce false detection of leakage due to noise without the need of providing hardware such as a noise filter. The present invention relates to a leakage detecting device that can be used and a bathroom air conditioner including the same.

  2. Description of the Related Art Conventionally, there is known a power supply device including a leakage detection means for detecting leakage. An example of this type of power supply device is disclosed in, for example, Japanese Patent Application Laid-Open No. 2003-87960. In the power supply device described in Japanese Patent Application Laid-Open No. 2003-87960, a ZCT coil for detecting current imbalance due to leakage is provided, a signal sent from the ZCT coil is amplified and input to a comparator, and the output of the comparator Whether or not leakage current is flowing, that is, whether or not leakage has occurred is determined.

  By the way, the signal sent from the ZCT coil may contain noise. If it is determined that a leakage has occurred based on this noise, the leakage may be erroneously detected although no leakage has actually occurred. Therefore, conventionally, a noise filter for removing noise included in a signal sent from the ZCT coil has been provided as hardware in order to reduce false detection of leakage. Therefore, the cost of the entire apparatus has increased.

JP 2003-87960 A

  In view of the above-described problems, the present invention provides a leakage detection device capable of reducing erroneous detection of leakage due to noise without requiring hardware such as a noise filter, and a bathroom air conditioner including the leakage detection device. With the goal.

  According to the first aspect of the present invention, in the leakage detection device for detecting leakage, the leakage signal generating means for generating a leakage signal when the leakage occurs, and the leakage transmitted from the leakage signal generating means There is provided a leakage detecting device comprising a determination unit for determining whether or not a signal is noise.

  According to the second aspect of the present invention, it is determined whether or not the leakage signal is noise based on the middle portion of the leakage signal sent from the leakage signal generating means. Is provided.

  According to the third aspect of the present invention, it is determined whether or not the leakage signal is noise based on whether or not the period of the leakage signal sent from the leakage signal generating means is within a predetermined range. An electrical leakage detection device according to claim 1 or 2 is provided.

  According to a fourth aspect of the present invention, there is provided the leakage detecting apparatus according to the third aspect, wherein the predetermined range is set based on an actual leakage signal period.

  According to the invention described in claim 5, the leakage detection device according to claim 4, wherein the predetermined range is set based on an operation of an electrical component included in a device to which the leakage detection device is applied. Is provided.

  According to the sixth aspect of the present invention, it is determined whether or not the leakage signal is noise based on whether or not the leakage signal has been repeatedly transmitted from the leakage signal generation means a predetermined number of times. An electrical leakage detection device according to any one of claims 1 to 5 is provided.

  According to a seventh aspect of the present invention, it is determined that a leakage has occurred when a leakage signal is repeatedly sent from the leakage signal generating means a predetermined number of times. A detection device is provided.

  According to invention of Claim 8, the bathroom air conditioner which comprises the electric leakage detection apparatus as described in any one of Claims 1-7 is provided.

  In the leakage detection device according to the first aspect, there is provided determination means for determining whether or not the leakage signal sent from the leakage signal generating means is noise. Specifically, a noise filter is not provided as hardware for removing the noise included in the leakage signal sent from the leakage signal generating means, but the leakage signal sent from the leakage signal generating means is noise, for example. It is determined on the software. Next, when it is determined that the leakage signal sent from the leakage signal generating means is not noise, it is determined that a leakage has actually occurred. Therefore, for example, it is not necessary to provide hardware such as a noise filter, and erroneous detection of leakage due to noise can be reduced.

  In view of the high possibility that the waveform of the initial part and the latter part of the leakage signal are likely to be disturbed, the leakage detection device according to claim 2 is based on the middle part of the leakage signal sent from the leakage signal generating means. It is determined whether or not the leakage signal is noise. Therefore, the reliability of leakage detection can be improved as compared with the case where it is determined whether or not the leakage signal is noise based on the initial portion or the late portion of the leakage signal sent from the leakage signal generating means.

  In view of the fact that the cycle of the leakage signal is uniquely determined from the frequency of the power supply applied to the leakage detection device, in the leakage detection device according to claim 3 and 4, the cycle of the leakage signal sent from the leakage signal generating means is It is determined whether or not the leakage signal is noise based on whether or not it falls within the predetermined range. Specifically, when the cycle of the leakage signal is longer or shorter than the predetermined range, it is determined that the leakage signal is noise. Therefore, the reliability of leakage detection can be improved as compared with the case where it is determined whether or not the leakage signal is noise without considering the cycle of the leakage signal sent from the leakage signal generating means. Preferably, the predetermined range is set based on the period of the actual leakage signal. Specifically, when the frequency of the power supply applied to the leakage detection device is 60 Hz, the actual cycle of the leakage signal is uniquely determined to be 16.67 msec, and the frequency of the power supply applied to the leakage detection device is 50 Hz. In view of the fact that the period of the actual leakage signal is uniquely determined to be about 20 msec, for example, when the frequency of the power supply applied to the leakage detection device is assumed to be 60 Hz or 50 Hz, the frequency of the power supply is 60 Hz. The predetermined range is set to, for example, 10 msec to 30 msec based on 16.67 msec that is the period of the actual leakage signal in the case of 20 and 20 msec that is the period of the actual leakage signal when the frequency of the power supply is 50 Hz. . Specifically, when the period of the leakage signal sent from the leakage signal generating means is longer than the predetermined range (10 msec to 30 msec) or less than the predetermined range (10 msec to 30 msec), the leakage signal Is determined to be noise.

  In view of the fact that the actual leakage signal cycle corresponds to the frequency of the power supply applied to the leakage detection device, the leakage detection device according to claim 5, wherein the leakage signal signal is transmitted from the leakage signal generating means. It is determined whether or not the leakage signal is noise based on whether or not the leakage current is included in a predetermined range. Preferably, the predetermined range is an operation of an electrical component included in a device to which the leakage detection device is applied. Is set based on Specifically, for example, when the frequency of the power supply applied to the leakage detection device is low, the operation of the electrical components included in the device to which the leakage detection device is applied is delayed. That is, the operation cycle of the electrical component becomes long. On the other hand, when the frequency of the power source applied to the leakage detection device is high, the operation of the electrical components included in the device to which the leakage detection device is applied becomes faster. That is, the operation cycle of the electrical component is shortened. In consideration of this point, in the leakage detection device according to claim 5, for example, an operation cycle of an electrical component included in the device to which the leakage detection device is applied is detected, and applied to the leakage detection device based on the operation cycle. The frequency of the power supply to be obtained is obtained, the actual leakage signal cycle is obtained based on the frequency, and the predetermined range is set based on the actual leakage signal cycle. Next, it is determined whether or not the cycle of the leakage signal sent from the leakage signal generating means is included in the predetermined range, and based on the result, it is determined whether or not the leakage signal is noise. Therefore, it is possible to set the predetermined range in a narrower range than the case where the predetermined range is set wider than the case where a plurality of values are assumed as the frequency of the power source applied to the leakage detection device. Can improve the reliability.

  In view of the fact that the leakage signal is less likely to be an actual leakage signal when the leakage signal is sent, for example, once from the leakage signal generating means, and that the leakage signal is likely to be noise. In the leakage detection device described in 1), it is determined whether or not the leakage signal is noise based on whether or not the leakage signal has been repeatedly sent from the leakage signal generating means a predetermined number of times, for example, four times. The Specifically, when the leakage signal is repeatedly transmitted from the leakage signal generation means, for example, four times, the leakage signal is an actual leakage signal, and it is determined that the leakage has actually occurred. Therefore, the reliability of leakage detection can be improved as compared with the case where it is determined whether or not the leakage signal is noise based on the leakage signal sent, for example, once from the leakage signal generating means.

  In the leakage detection device according to the seventh aspect, it is determined that the leakage has occurred when the leakage signal is repeatedly sent from the leakage signal generating means a predetermined number of times. Therefore, for example, by setting the predetermined number of times so that it is determined that a leakage has occurred before the leakage breaker is activated, the operation of the device to which the leakage detection device is applied before the leakage breaker is activated. Can be stopped. That is, when a leakage occurs, the operation of the device to which the leakage detection device is applied can be stopped without operating the leakage breaker.

  In the bathroom air conditioner according to the eighth aspect of the present invention, there is provided determination means for determining whether or not the leakage signal sent from the leakage signal generating means is noise. Specifically, a noise filter is not provided as hardware for removing the noise included in the leakage signal sent from the leakage signal generating means, but the leakage signal sent from the leakage signal generating means is noise, for example. It is determined on the software. Next, when it is determined that the leakage signal sent from the leakage signal generating means is not noise, it is determined that a leakage has actually occurred. Therefore, for example, it is not necessary to provide hardware such as a noise filter, and erroneous detection of leakage due to noise can be reduced.

  FIG. 1 is a cross-sectional view of a bathroom air conditioner to which the first embodiment of the leakage detection apparatus of the present invention is applied. FIG. 2 is a view showing a bathroom to which the bathroom air conditioner shown in FIG. 1 is applied. 1 and 2, reference numeral 10 denotes a bathroom air conditioner, 12 denotes a casing of the bathroom air conditioner 10, and 13 denotes an air inlet for sucking indoor air to which the bathroom air conditioner 10 is applied into the bathroom air conditioner 10. 14 is an outlet for blowing out the air sucked into the bathroom air conditioner 10 into the room and circulating it, 15 is an outlet for discharging the air sucked into the bathroom air conditioner 10 to the outside, and 15 ′ is an exhaust. A duct connected to the mouth 15. D is a damper for switching whether the air sucked into the bathroom air conditioner 10 is blown out into the room for circulation or discharged outside the room. The damper D is driven by a synchronous motor that rotates in synchronization with the power supply frequency. F1 is a fan that sucks indoor air into the bathroom air conditioner 10 and blows out the air into the room for circulation or exhausts the air outside the room. M is a motor for driving the fan F1. H is a heater for heating the air blown into the room and circulated.

  20 is a bathroom to which the bathroom air conditioner 10 is applied, 21 is a bathtub, 22 is a laundry pipe for drying laundry, 23 is an inspection port, and 24 is a gallery for taking air into the bathroom 10. Reference numeral 30 is a washroom, 31 is an operation unit for operating the bathroom air conditioner 20, 32 is a master / wiring circuit breaker, 33 is a leakage breaker (leakage breaker), and 34 is a branch / wiring breaker.

  In the bathroom air conditioner to which the leakage detection device of the first embodiment is applied, a heating mode for heating and circulating indoor air is provided. When the heating mode is selected and the heating operation is started, as shown in FIG. 1, the damper D is disposed at a position (D) indicated by a solid line. Next, the air sucked into the bathroom air conditioner 10 through the air inlet 13 by the fan F <b> 1 is guided by the damper D, heated by the heater H, and blown out into the room through the air outlet 14.

  Furthermore, in the bathroom air conditioner to which the leakage detection device of the first embodiment is applied, a ventilation mode for discharging indoor air to the outside is provided. When the ventilation mode is selected and the ventilation operation is started, as shown in FIG. 1, the damper D is disposed at a position (D ′) indicated by a two-dot chain line. Next, the air sucked into the bathroom air conditioner 10 through the air inlet 13 by the fan F1 is guided by the damper D disposed at the position (D ′) indicated by the two-dot chain line, and is outdoors through the air outlet 15. To be discharged.

  Further, in the air conditioner to which the leakage detection device of the first embodiment is applied, a drying mode is provided in which a part of the indoor air is discharged outside the room while a part of the indoor air is heated and circulated. Yes. When the drying mode is selected and the drying operation is started, the damper D is disposed at a position between the position (D) indicated by the solid line and the position (D ′) indicated by the two-dot chain line. Next, a part of the air sucked into the bathroom air conditioner 10 through the air inlet 13 by the fan F <b> 1 is guided by the damper D, heated by the heater H, and blown out into the room through the air outlet 14. Further, the remainder of the air sucked into the bathroom air conditioner 10 through the air inlet 13 by the fan F1 is guided by the damper D and discharged to the outside through the air outlet 15. This drying mode is a function of hanging laundry on the laundry pipe 22 shown in FIG. 2 using a hanger (not shown) or the like and drying it, and uses the bathroom as a drying room.

  Furthermore, in the bathroom air conditioner to which the leakage detection device of the first embodiment is applied, a cool air mode for circulating indoor air without heating is provided. When the cool breeze mode is selected and the cool breeze operation is started, the damper D is positioned at a position between the position (D) indicated by the solid line and the position (D ′) indicated by the two-dot chain line, as in the drying operation. Be placed. Next, the air sucked into the bathroom air conditioner 10 by the fan F1 through the air inlet 13 is guided by the damper D and blown into the room through the air outlet 14 without being heated by the heater H. The remainder of the air sucked into the bathroom air conditioner 10 through the air inlet 13 by the fan F1 is guided by the damper D and discharged to the outside through the air outlet 15. The cool breeze mode allows you to take a cool bath in summer.

  FIG. 3 is an electric circuit diagram of the leakage detection device of the first embodiment applied to the bathroom air conditioner 10 shown in FIGS. 1 and 2. In FIG. 3, reference numeral 40 denotes a leakage detection device according to the first embodiment, 42 denotes a wire mesh, and 43 denotes a frame that supports the wire mesh 42. In FIG. 3, the wire mesh 42 and the frame body 43 are arranged on the upper side of the heater H. However, actually, the wire mesh 42 and the frame body 43 are located on the lower side of the heater H, that is, on the bathtub 21 side (see FIGS. It is arranged on the lower side of FIG. 44 and 45 are heater cables, 46 is an AC power source, and 47 is a ZCT coil (zero phase current transformer) for detecting an imbalance between the current Ia flowing through the heater cable 44 and the current Ib flowing through the heater cable 45. Reference numeral 47A denotes a signal line for sending a pulsed leakage signal generated in the ZCT coil (zero phase current transformer) 47 when an imbalance between the currents Ia and Ib is detected due to the leakage. 48 is a leakage detection circuit, and 48A is for determining whether or not the pulsed leakage signal sent from the ZCT coil (zero phase current transformer) 47 to the leakage detection circuit 48 via the signal line 47A is noise. It is a determination means. Reference numeral 49 denotes a switch for cutting off the electric circuit of the leakage detection device 40 when it is determined by the determination means 48A that an actual leakage has occurred, and reference numeral 50 denotes a reset circuit for sending a signal for opening the switch 49. 11 is a ground wire.

  As shown in FIG. 3, in the bathroom air conditioner to which the leakage detection device 40 of the first embodiment is applied, for example, three heaters H are connected in parallel to the AC power source 46. In addition, a leakage breaker (leakage breaker) 33 for cutting off the electric circuit of the leakage detection device 40, and a switch 49 for cutting off the electric circuit of the leakage detection device 40 before the leakage breaker 33 is activated, The AC power supply 46 is connected in series. During the heating operation and the drying operation described above, the heater H is energized from the AC power source 46.

  When the heater H is energized from the AC power source 46, for example, when the shower H gets wet and the heater H gets wet, the current Ic flows through the ground wire 11 and an electric leakage may occur. Despite the occurrence of electric leakage, if energization to the heater H from the AC power source 46 is continued, there is a risk of safety inconvenience. Therefore, in the leakage detection device 40 of the first embodiment, when the current Ic flows and a leakage occurs, that is, when an imbalance between the currents Ia and Ib occurs, the AC power supply 46 is energized to the heater H. It is supposed to be stopped. Specifically, when the current Ic flows, the current Ib becomes smaller than the current Ia, and a pulse-like leakage signal is generated in the ZCT coil (zero-phase current transformer) 47. The leakage signal is sent to the leakage detection circuit 48 via the signal line 47A and amplified, and the determination unit 48A determines whether or not the pulsed leakage signal is noise. When it is determined that the signal sent from the ZCT coil (zero phase current transformer) 47 is not noise but an actual leakage signal, the leakage detection circuit 48 sends a signal a to the reset circuit 50 to reset it. The switch 49 is opened by the signal b from the signal 50, and the electric circuit of the leakage detection device 40 is disconnected. Thereby, the energization from the AC power supply 46 to the heater H is stopped.

  FIG. 4 is a diagram showing an example of a pulsed leakage signal sent from the ZCT coil (zero-phase current transformer) 47 to the leakage detection circuit 48 when the leakage actually occurs. Specifically, FIG. 4 (A) shows two pulse leakage signals when the frequency of the AC power supply 46 is 50 Hz, and FIG. 4 (B) shows the two pulses shown in FIG. 4 (A). FIG. 4C is an enlarged view showing one of the pulsed leakage signals, FIG. 4C is a diagram showing two pulsed leakage signals when the frequency of the AC power supply 46 is 60 Hz, and FIG. FIG. 4D is an enlarged view of one of the two pulsed leakage signals shown in FIG.

  As shown in FIGS. 4 (A) and 4 (B), when the frequency of the AC power supply 46 is 50 Hz, the length of one pulsed leakage signal is about 6 msec, and the period of the leakage signal, That is, the length from the falling portion of a certain leakage signal to the falling portion of the next leakage signal is 20 msec. On the other hand, as shown in FIG. 4C and FIG. 4D, when the frequency of the AC power supply 46 is 60 Hz, the length of one pulsed leakage signal is about 5 msec, The period, that is, the length from the falling portion of a certain leakage signal to the falling portion of the next leakage signal is 16.67 msec. The actual leakage signal sent from the ZCT coil (zero-phase current transformer) 47 to the leakage detection circuit 48 is not a clean rectangular shape as shown by the solid line in FIGS. 4B and 4D. As shown by broken lines in (B) and FIG. 4 (D), there is a high possibility that the waveform of the leakage signal is disturbed in the initial part and the latter part of the leakage signal. Therefore, in the leakage detection device 40 of the first embodiment, when determining whether or not the leakage signal sent from the ZCT coil (zero phase current transformer) 47 is noise, the leakage signal is described later. A determination is made based on the mid-term portion.

  Further, in the leakage detection device 40 of the first embodiment, a noise filter is not provided as hardware for removing noise included in the leakage signal sent from the ZCT coil (zero-phase current transformer) 47. , Whether or not the pulsed leakage signal sent from the ZCT coil (zero phase current transformer) 47 is noise, that is, the leakage signal sent from the ZCT coil (zero phase current transformer) 47 is the actual leakage current. Whether it is a signal or not is determined by software.

  Specifically, in the leakage detection device 40 of the first embodiment, the length from the falling portion of a certain leakage signal sent to the leakage detection circuit 48 to the falling portion of the next leakage signal, that is, the leakage A counter C1 for identifying the signal period and a counter C2 for identifying the number of repetitions of the leakage signal sent to the leakage detection circuit 48 are set, and leakage detection is performed based on the numerical values of the counters C1 and C2. It is determined whether or not the leakage signal sent to the circuit 48 is noise, that is, whether or not the leakage signal sent to the leakage detection circuit 48 is an actual leakage signal.

  The counter C1 is basically incremented by 1 every 1 msec. Further, the counter C1 is reset to zero when a falling portion (see FIG. 4) of the pulsed leakage signal is detected, and is similarly reset when it increases to 30 counts (C1 = 30). On the other hand, the counter C2 is incremented by 1 every time a falling part (see FIG. 4) of the pulsed leakage signal whose period of the leakage signal exceeds 10 msec is detected, and the period of the leakage signal is 10 msec or less. When a falling portion (see FIG. 4) of the ground leakage signal is detected, it is forcibly set to 1. In addition, since the length of the pulsed leakage signal is short, that is, the interval between the falling part and the rising part of the pulsed leakage signal is short, the leakage is caused when the counter C1 = 2 or when the counter C1 = 3. If the signal does not go low, it is forced to zero.

  5 and 6 are flowcharts showing a method for determining a leakage signal in the leakage detection device 40 of the first embodiment. Specifically, FIG. 5 is a routine for controlling the counter C1, and FIG. 6 is a routine for controlling the counter C2.

  The routine shown in FIG. 5 is started when, for example, a falling portion of a pulsed leakage signal is first detected after energization of the heater H is started. As shown in FIG. 5, when this routine is started, it is first determined in step 100 whether or not 1 msec has elapsed. If YES, the process proceeds to step 101. If NO, the process proceeds to step 105. In step 101, the counter C1 is incremented by 1, and the process proceeds to step 102. In step 102, it is determined whether or not the falling portion of the next pulsed leakage signal has been detected. If yes, then continue with step 104, otherwise continue with step 103. In step 103, it is determined whether or not the counter C1 is 30 or less. If yes, then continue with step 105, otherwise continue with step 104. In step 104, the counter C1 is cleared to zero, and the process proceeds to step 105. In step 105, it is determined whether or not abnormality processing described later is being performed. When the determination is YES, this routine is terminated. When the determination is NO, the routine returns to step 100, and the above steps are repeated. Further, for example, when the energization to the heater H is stopped, this routine is also ended.

  The routine shown in FIG. 6 is started when, for example, the falling portion of the pulse leakage current signal is first detected after the energization of the heater H is started, for example, similarly to the routine shown in FIG. As shown in FIG. 6, when this routine is started, first, at step 200, it is determined whether or not a falling portion of a pulsed leakage signal has been detected. If YES, the process proceeds to step 201, and if NO, the process proceeds to step 203. In step 201, the counter C2 is incremented by 1, and the process proceeds to step 203. In step 203, it is determined whether or not the counter C1 immediately before the falling portion of the pulsed leakage signal is detected is greater than 10. If yes, go to step 205. On the other hand, when NO, since the cycle of the leak signal detected last time is shorter than the cycle of the actual leak signal, the pulse leak signal detected last time is regarded as noise, and the counter C2 is set to 1 in step 204. And go to Step 205.

  In step 205, it is determined whether or not the counter C1 is maintained at 30 or less. If YES, the process proceeds to step 207. On the other hand, when NO, that is, when the counter C1 exceeds 30, the cycle of the currently detected leakage signal is longer than the cycle of the actual leakage signal, and the currently detected pulse leakage signal is noise. In step 206, the counter C1 is cleared to zero, and the process proceeds to step 207. If NO is determined in step 205 and step 206 is executed, NO is substantially determined in step 103 shown in FIG. 5 and step 104 is executed. In step 207, it is determined whether or not the leakage signal when the counter C1 = 2 is at the low level. If YES, the process proceeds to step 208. On the other hand, when NO, since the length of the pulse-shaped leakage signal detected this time is shorter than the length of the actual pulse-shaped leakage signal, the pulse-shaped leakage signal detected this time is regarded as noise. The process proceeds to step 209. In step 208, it is determined whether or not the leakage signal when the counter C1 = 3 is at the low level. If yes, go to step 210. On the other hand, when NO, since the length of the pulse-shaped leakage signal detected this time is shorter than the length of the actual pulse-shaped leakage signal, the pulse-shaped leakage signal detected this time is regarded as noise. The process proceeds to step 209. In step 209, the counter C2 is cleared to zero, and the process proceeds to step 210.

  In step 210, it is determined whether or not the counter C2 has reached 4. In the case of YES, since the actual leakage signal has been repeatedly sent four times, it is considered that a leakage has actually occurred, and the process proceeds to step 211. On the other hand, when the answer is NO, the reliability that can be regarded as the actual occurrence of electric leakage has not been obtained, so the process returns to step 200 and the above steps are repeated. In step 211, abnormality processing is performed and this routine is terminated. Specifically, in step 211, the signal a is sent from the leakage detection circuit 48 to the reset circuit 50, the switch 49 is opened by the signal b from the reset signal 50, and the electric circuit of the leakage detection device 40 is disconnected. Thereby, the energization from the AC power supply 46 to the heater H is stopped. In addition, the fact that a leakage has occurred is displayed on the operation unit 31 of the bathroom air conditioner 10.

  FIG. 7 shows an example in which it is determined that an actual leakage has occurred, and an example in which it is determined that the pulsed leakage signal sent from the ZCT coil (zero-phase current transformer) 47 to the leakage detection circuit 48 is noise. FIG.

  Specifically, in FIG. 7A, when the frequency of the AC power supply 46 is 50 Hz, it is determined that the pulsed leakage signal sent from the ZCT coil (zero-phase current transformer) 47 to the leakage detection circuit 48 is not noise. An example is shown in which it is determined that a leakage has actually occurred. As shown in FIG. 7 (A), after the energization of the heater H is started, the first time when the falling portion of the pulsed leakage signal is detected (A1), the routine shown in FIG. The routine shown in FIG. Specifically, when it is determined as YES in Step 200 and Step 201 is executed, the counter C2 is incremented by 1 from zero and becomes 1. Thereafter, it is determined as YES in Step 100 and the execution of Step 101 is continued, whereby the counter C1 is incremented by 1 every 1 msec.

  Next, when counter C1 = 2 (A2), it is determined in step 207 that the leakage signal is at the low level, and step 209 is not executed, and counter C2 is maintained at 1. Next, when counter C1 = 3 (A3), it is determined in step 208 that the leakage signal is at the low level, and step 209 is not executed, and counter C2 is maintained at 1.

  Next, when the falling portion of the next pulse leakage signal is detected (A4), it is determined YES in step 102, and step 104 is executed to set the counter C1 to zero. At that time (A4), YES is determined in step 200, and step 201 is executed to increase the counter C2 from 1 to 1. At this time (A4), since it is determined as YES in Step 203, Step 204 is not executed and the counter C2 is maintained at 2.

  Next, when counter C1 = 2 (A5), it is determined in step 207 that the leakage signal is at the low level, and step 209 is not executed, and counter C2 is maintained at 2. Next, when counter C1 = 3 (A6), it is determined in step 208 that the leakage signal is at the low level, and step 209 is not executed, and counter C2 is maintained at 2.

  Next, when the falling portion of the next pulse leakage signal is detected (A7), it is determined YES in step 102, step 104 is executed, and the counter C1 is set to zero. At that time (A7), YES is determined in step 200, step 201 is executed, and the counter C2 is incremented by 1 from 2 to 3. At this time (A7), since it is determined as YES in Step 203, Step 204 is not executed and the counter C2 is maintained at 3.

  Next, when counter C1 = 2 (A8), it is determined in step 207 that the leakage signal is at the low level, and step 209 is not executed, and counter C2 is maintained at 3. Next, when counter C1 = 3 (A9), it is determined in step 208 that the leakage signal is at the low level, and step 209 is not executed, and counter C2 is maintained at 3.

  Next, when the falling portion of the next pulse leakage signal is detected (A10), YES is determined in step 102, and step 104 is executed to set the counter C1 to zero. At that time (A10), YES is determined in step 200, step 201 is executed, and the counter C2 is incremented by 1 from 3 to 4. At this time (A10), it is determined as YES in Step 211, and it is considered that an actual electric leakage has occurred because the actual electric leakage signal has been repeatedly sent four times. In Step 211, an abnormal process is executed. Specifically, as described above, the signal a is sent from the leakage detection circuit 48 to the reset circuit 50, the switch 49 is opened by the signal b from the reset signal 50, and the electric circuit of the leakage detection device 40 is disconnected. . Thereby, the energization from the AC power supply 46 to the heater H is stopped. In addition, the fact that a leakage has occurred is displayed on the operation unit 31 of the bathroom air conditioner 10. Specifically, it can be determined that the leakage has occurred when 60 msec has elapsed since the occurrence of the leakage (A1) (A10). For example, even when 12 msec is required from the determination (A10) to the completion of the energization stop process, the energization can be stopped when 72 msec has elapsed since the occurrence of the electric leakage (A1). When the frequency of the AC power supply is 60 Hz, it can be determined that the leakage has occurred when 50 msec has elapsed since the occurrence of the leakage.

  FIG. 7B shows the period of the pulsed leakage signal sent from the ZCT coil (zero phase current transformer) 47 to the leakage detection circuit 48, that is, the next pulse from the falling portion of a certain pulsed leakage signal. In this example, the length of the leakage current signal in the form of a short circuit is short, so that the leakage signal is determined to be noise. As shown in FIG. 7B, after the energization of the heater H is started, when the falling portion of the pulsed leakage signal is first detected (B1), the routine shown in FIG. The routine shown in FIG. Specifically, when it is determined as YES in Step 200 and Step 201 is executed, the counter C2 is incremented by 1 from zero and becomes 1. Thereafter, it is determined as YES in Step 100 and the execution of Step 101 is continued, whereby the counter C1 is incremented by 1 every 1 msec.

  Next, when counter C1 = 2 (B2), it is determined in step 207 that the leakage signal is at the low level, and step 209 is not executed, and counter C2 is maintained at 1. Next, when counter C1 = 3 (B3), it is determined in step 208 that the leakage signal is at the low level, and step 209 is not executed, and counter C2 is maintained at 1.

  Next, when the falling portion of the next pulse leakage signal is detected (B4), it is determined as YES in Step 102, and Step 104 is executed to set the counter C1 to zero. At that time (B4), YES is determined in step 200, and step 201 is executed to increase the counter C2 from 1 to 1. However, at this time (B4), since it is determined as NO in Step 203, Step 204 is executed and the counter C2 is returned to 1. That is, in step 203, the length from the falling portion (B1) of the pulsed leakage signal to the falling portion (B4) of the next pulsed leakage signal, that is, the period of the pulsed leakage signal is short. In addition, it is determined that the leakage signal is noise.

  Next, when counter C1 = 2 (B5), it is determined in step 207 that the leakage signal is at the low level, and step 209 is not executed, and counter C2 is maintained at 1. Next, when counter C1 = 3 (B6), it is determined in step 208 that the leakage signal is at the low level, and step 209 is not executed, and counter C2 is maintained at 1.

  Next, when the falling portion of the next pulse leakage signal is detected (B7), YES is determined in step 102, and step 104 is executed to set the counter C1 to zero. At that time (B7), YES is determined in step 200, step 201 is executed, and the counter C2 is incremented by 1 from 1 to 2. However, at this time (B7), since it is determined as NO in Step 203, Step 204 is executed and the counter C2 is returned to 1. That is, in step 203, the length from the falling portion (B4) of the pulsed leakage signal to the falling portion (B7) of the next pulsed leakage signal, that is, the period of the pulsed leakage signal is short. In addition, it is determined that the leakage signal is noise.

  FIG. 7C shows the period of the pulsed leakage signal sent from the ZCT coil (zero phase current transformer) 47 to the leakage detection circuit 48, that is, the next pulse from the falling portion of a certain pulsed leakage signal. In this example, the length of the leakage current signal in the form of a ground leakage signal is long, so that the leakage signal is determined to be noise. As shown in FIG. 7 (C), after the energization of the heater H is started, the routine shown in FIG. 5 and the routine shown in FIG. The routine shown in FIG. Specifically, when it is determined as YES in Step 200 and Step 201 is executed, the counter C2 is incremented by 1 from zero and becomes 1. Thereafter, it is determined as YES in Step 100 and the execution of Step 101 is continued, whereby the counter C1 is incremented by 1 every 1 msec.

  Next, when counter C1 = 2 (D2), it is determined in step 207 that the leakage signal is at the low level, and step 209 is not executed, and counter C2 is maintained at 1. Next, when counter C1 = 3 (D3), it is determined in step 208 that the leakage signal is at the low level, and step 209 is not executed, and counter C2 is maintained at 1.

  Next, when the counter C1 exceeds 30 (D4), NO is determined in step 205, and the counter C1 is cleared to zero in step 206. In effect, when the counter C1 exceeds 30 (D4), it is determined NO in Step 103, and Step 104 is executed to clear the counter C1 to zero.

  Next, when the counter C1 = 2 (D5), it is determined in step 207 that the leakage signal is not at the low level, and step 209 is executed to clear the counter C2 to zero. Next, when counter C1 = 3 (D6), it is determined in step 208 that the leakage signal is not at the low level, and step 209 is executed to clear counter C2 to zero.

  That is, if the counter C1 is cleared to zero beyond 30 (D4) and the leak signal is not at the low level when the counter C1 = 2 (D5) thereafter, the cycle of the currently detected leak signal is A pulsed leakage signal that is longer than the actual leakage signal period and is currently detected is considered to be noise.

  FIG. 7D shows that the length of the pulsed leakage signal sent from the ZCT coil (zero phase current transformer) 47 to the leakage detection circuit 48 is short, that is, the falling portion and rising portion of the pulsed leakage signal. In this example, the leakage signal is determined to be noise because of the short interval. As shown in FIG. 7 (D), after the energization of the heater H is started, when the falling portion of the pulsed leakage signal is first detected (E1), the routine shown in FIG. The routine shown in FIG. Specifically, when it is determined as YES in Step 200 and Step 201 is executed, the counter C2 is incremented by 1 from zero and becomes 1. Thereafter, it is determined as YES in Step 100 and the execution of Step 101 is continued, whereby the counter C1 is incremented by 1 every 1 msec.

  Next, when the counter C1 = 2 (E2), it is determined in step 207 that the leakage signal is not at the low level, and step 209 is executed to clear the counter C2 to zero. Next, when the counter C1 = 3 (E3), it is determined in step 208 that the leakage signal is not at the low level, and step 209 is executed to clear the counter C2 to zero.

  That is, when the falling portion of the pulse leakage signal is detected (E1) and the leakage signal is not at the low level when the counter C1 = 2 thereafter (E2), the length of the detected pulse leakage signal is long. Is shorter than the length of the actual pulse leakage signal, and the detected pulse leakage signal is regarded as noise.

  In the bathroom air conditioner 10 to which the leakage detection device 40 of the first embodiment is applied, as shown in FIG. 3, the leakage signal sent from the ZCT coil (zero phase current transformer) 47 as the leakage signal generating means. 48A is provided for determining whether or not is noise. More specifically, a noise filter is not provided as hardware for removing noise contained in a leakage signal sent from a ZCT coil (zero-phase current transformer) 47 serving as a leakage signal generation means, but a leakage signal is generated. In step 203, step 205, step 207, and step 208, it is determined whether or not the leakage signal sent from the ZCT coil (zero-phase current transformer) 47 as means is noise. Next, when it is determined in those steps that the leakage signal sent from the ZCT coil (zero-phase current transformer) 47 serving as the leakage signal generation means is not noise, it is determined that the leakage has actually occurred. Therefore, for example, it is not necessary to provide hardware such as a noise filter, and erroneous detection of leakage due to noise can be reduced.

  Further, in the bathroom air conditioner 10 to which the leakage detection device 40 of the first embodiment is applied, the middle portion of the leakage signal sent from the ZCT coil (zero phase current transformer) 47 as the leakage signal generating means (FIG. 4). Based on (B) and FIG. 4D), it is determined in step 207 and step 208 whether or not the leakage signal is noise. Therefore, based on the initial part or the latter part of the leakage signal sent from the ZCT coil (zero phase current transformer) 47 as the leakage signal generating means (see FIG. 4B and FIG. 4D), the leakage The reliability of leakage detection can be improved compared to the case where it is determined whether or not the signal is noise.

  Furthermore, in the bathroom air conditioner 10 to which the leakage detection device 40 of the first embodiment is applied, the cycle of the leakage signal sent from the ZCT coil (zero-phase current transformer) 47 as the leakage signal generating means is within a predetermined range ( In step 203 and step 205, it is determined whether or not the leakage signal is noise based on whether or not it is included in the range of 10 msec to 30 msec. Specifically, when the cycle of the leakage signal is longer or shorter than the predetermined range (10 msec to 30 msec), the leakage signal is regarded as noise. Specifically, the predetermined range (10 msec to 30 msec) is set based on the period of the actual pulse-shaped leakage signal. That is, as shown in FIG. 4, when the frequency of the AC power supply 46 applied to the leakage detection device 40 is 60 Hz, the actual pulse-shaped leakage signal period is uniquely determined to be 16.67 msec. In view of the fact that when the frequency of the AC power supply 46 applied to the apparatus 40 is 50 Hz, the period of the actual pulsed leakage signal is uniquely determined to be about 20 msec, the actual frequency when the frequency of the AC power supply 46 is 60 Hz is considered. The predetermined range is set to 10 msec to 30 msec based on 16.67 msec which is the period of the pulsed leakage signal and 20 msec which is the period of the actual pulsed leakage signal when the frequency of the AC power supply 46 is 50 Hz. Is done. Specifically, when the cycle of the pulsed leakage signal sent from the ZCT coil (zero phase current transformer) 47 as the leakage signal generating means is longer than the predetermined range (10 msec to 30 msec), in step 205 In the case where the predetermined range (10 msec to 30 msec) or less is reached, in step 203, the leakage signal is regarded as noise. Therefore, rather than the case where it is determined whether or not the leakage signal is noise without considering the cycle of the leakage signal sent from the ZCT coil (zero phase current transformer) 47 as the leakage signal generation means, The reliability of leakage detection can be increased.

  Moreover, in the bathroom air conditioner 10 to which the leakage detection device 40 of the first embodiment is applied, the leakage signal is repeatedly transmitted four or more times from the ZCT coil (zero phase current transformer) 47 as the leakage signal generating means. In step 210, it is determined whether or not the leakage signal is noise. Specifically, when a leakage signal is repeatedly sent four times from a ZCT coil (zero-phase current transformer) 47 serving as a leakage signal generating means, the leakage signal is an actual leakage signal, and the leakage actually occurs. It is determined that it has occurred. Therefore, the leakage detection is performed rather than the case where it is determined whether or not the leakage signal is noise based on the leakage signal sent from the ZCT coil (zero-phase current transformer) 47 serving as the leakage signal generating means once, for example. Can improve the reliability.

  Furthermore, in the bathroom air conditioner 10 to which the leakage detection device 40 of the first embodiment is applied, the leakage signal has been repeatedly transmitted four times from the ZCT coil (zero phase current transformer) 47 as the leakage signal generation means. In step 210, it is determined that a leakage has occurred. Specifically, the number of times of four is set so that it is determined in step 210 that a leakage has occurred before the leakage breaker 33 is activated. Therefore, energization to the heater H to which the leakage detection device 40 is applied can be stopped before the leakage breaker 33 is activated, that is, before 100 msec elapses from the occurrence of the leakage. That is, when a leakage occurs, energization to the heater H to which the leakage detection device 40 is applied can be stopped without operating the leakage breaker.

  In the first embodiment described above, energization to the heater H is stopped when a leakage occurs. However, in the modification of the first embodiment, energization to the entire bathroom air conditioner 10 occurs when a leakage occurs. It is also possible to stop.

  Hereinafter, a second embodiment of the leakage detection apparatus of the present invention will be described. The leakage detection device of the second embodiment is configured in substantially the same manner as the leakage detection device of the first embodiment described above, except for the points described below. Therefore, it is possible to achieve substantially the same effect as the leakage detection device of the first embodiment described above.

  As described above, in the bathroom air conditioner 10 to which the leakage detection device 40 of the first embodiment is applied, the cycle of the leakage signal sent from the ZCT coil (zero phase current transformer) 47 as the leakage signal generating means is In step 203 and step 205, it is determined whether or not the leakage signal is noise based on whether or not the leakage signal is included in a predetermined range (10 msec to 30 msec). That is, in the bathroom air conditioner 10 to which the leakage detection device 40 of the first embodiment is applied, the leakage signal sent from the ZCT coil (zero phase current transformer) 47 as the leakage signal generating means is the actual leakage signal. The threshold value of the cycle of the leakage signal for determining whether or not there is fixedly set at 10 msec and 30 msec. On the other hand, in the bathroom air conditioner to which the leakage detection device of the second embodiment is applied, the cycle of the rotational operation required for one reciprocation of the damper D shown in FIG. 1 is detected, and leakage detection is performed based on the operation cycle. The frequency of the AC power supply 46 applied to the apparatus is calculated, the actual leakage signal period (see FIG. 4) is obtained based on the frequency, and the determination threshold is determined based on the actual leakage signal period. Is set. For example, when the period of the actual leakage signal sent from the ZCT coil (zero phase current transformer) 47 serving as the leakage signal generating means is 20 msec, for example, 15 msec and 25 msec are set as threshold values for the determination period. For example, when the period of the actual leakage signal sent from the ZCT coil (zero-phase current transformer) 47 serving as the leakage signal generating means is 16.67 msec, 10 msec and 20 msec are used as the determination cycle threshold values, for example. Is set. That is, the threshold value for the period for determination is changed according to the frequency of the AC power supply 46 applied to the leakage detection device. Therefore, it is possible to set the width of the two thresholds narrower than the case where the width of the two thresholds is set to be wider assuming a plurality of values as the frequency of the power source applied to the leakage detection device, The reliability of leakage detection can be increased.

  In the first and second embodiments described above, the ZCT coil (zero-phase current transformer) 47 is used as the leakage signal generating means, but in the third embodiment, any other arbitrary leakage current generating means is used. Equipment can be used. For example, it is possible to generate a leakage signal based on the current Ic flowing through the ground wire 11.

It is sectional drawing of the bathroom air conditioner to which 1st Embodiment of the leak detection apparatus of this invention is applied. It is the figure which showed the bathroom etc. which applied the bathroom air conditioner shown in FIG. FIG. 3 is an electric circuit diagram of a leakage detection device of a first embodiment applied to the bathroom air conditioner 10 shown in FIGS. 1 and 2. It is the figure which showed the example of the pulse-form electric leakage signal sent to the electric leakage detection circuit 48 from the ZCT coil (zero phase current transformer) 47 when electric leakage actually occurs. It is the flowchart which showed the determination method of the leak signal in the leak detection apparatus 40 of 1st Embodiment. It is the flowchart which showed the determination method of the leak signal in the leak detection apparatus 40 of 1st Embodiment. A diagram showing an example in which it is determined that an actual leakage has occurred and an example in which it is determined that the pulsed leakage signal sent from the ZCT coil (zero-phase current transformer) 47 to the leakage detection circuit 48 is noise. It is.

Explanation of symbols

10 Bathroom air conditioner D Damper H Heater 33 Earth leakage breaker (earth leakage breaker)
40 Leakage detector 47 ZCT coil (zero phase current transformer)
48 leakage detection circuit 48A determination means 49 switch 50 reset circuit

Claims (8)

  In a leakage detection device for detecting a leakage, a leakage signal generating means for generating a leakage signal when a leakage occurs, and determining whether or not the leakage signal sent from the leakage signal generating means is noise An electrical leakage detection device comprising: a determination means for detecting the leakage current.   2. The leakage detecting device according to claim 1, wherein it is determined whether or not the leakage signal is noise based on a medium-term portion of the leakage signal sent from the leakage signal generating means.   3. The method according to claim 1, wherein the leakage signal is determined to be noise based on whether or not a cycle of the leakage signal sent from the leakage signal generating means is within a predetermined range. The leakage detection device described in 1.   The leakage detection device according to claim 3, wherein the predetermined range is set based on an actual leakage signal period.   The leakage detection device according to claim 4, wherein the predetermined range is set based on an operation of an electrical component included in a device to which the leakage detection device is applied.   6. The method according to claim 1, wherein it is determined whether or not the leakage signal is noise based on whether or not the leakage signal has been repeatedly transmitted from the leakage signal generation unit a predetermined number of times. The leakage detection device according to one item.   The leakage detecting device according to claim 6, wherein when the leakage signal is repeatedly sent from the leakage signal generating unit a predetermined number of times, it is determined that a leakage has occurred.   A bathroom air conditioner comprising the leakage detecting device according to any one of claims 1 to 7.

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