JP2007114153A - Water detection device and wireless device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance the detection performance of a submerging state and a surfaced state of a surfacing detection device 10, and improve its followability to switching between the submerging state and the surfacing state. <P>SOLUTION: A comparator 26 generates a high-level output for TP1≥TP2, and generates a low-level output for TP1<TP2, when the voltages of the noninverting-side and the inverting-side input terminals of the comparator are TP1 and TP2, respectively. The threshold TP2 is adjusted on the basis of a water temperature detected by a temperature sensor 32. A clock pulse signal is supplied to a terminal 20 from a CPU. In submerged periods, the part between electrodes 12-13 is filled with water, and the part between the electrodes 12-13 becomes conductive. As a result, an alternating current related to the clock pulse signal flows between the electrodes 12-13 via a capacitor 22. The alternating current is fed to a smoothing portion 25, after being rectified in a rectification portion 24, and TP1(≥TP2) is generated. At surfacing periods, the section between electrodes 12-13 is interrupted, and results in TP1<TP2. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a water detection device that detects the presence or absence of water and a wireless device equipped with the water detection device.

  Biological observations are being carried out to monitor the position of marine organisms (sea turtles, whales, dolphins, etc.) equipped with wireless devices such as transmitters and GPS receivers. In such ecological observation, there is a strong demand for miniaturization and weight reduction of wireless devices and long-term operation with a battery (reduction of power consumption of wireless devices) in order to minimize the influence on the organism.

  In response to this, in the ecological observation of marine life, a wireless device attached to the marine life is equipped with a sensor, and based on the output of the sensor, it is monitored whether the marine life has surfaced on the sea surface. Only during the period when the antenna is exposed to the atmosphere, the wireless device is operated to transmit and receive radio waves with GPS satellites and other satellites. That is, when the wireless device is in the sea, it is difficult to execute wireless communication. Therefore, the wireless device is turned off and the wireless operation is stopped to save power. For the purpose of feeding (breast feeding), the wireless device is operated and wireless communication is performed only during the period of rising to the sea surface (Patent Document 1).

  The sensor of patent document 1 equips with an electrode pair, and utilizes the fact that the electrical resistance between the electrodes of an electrode pair becomes small during submergence due to the water interposed between the electrodes of the electrode pair. In the sensor, the current flowing between the electrodes of the electrode pair is regulated to alternating current in a submerged state of the sensor to suppress electrode contact.

  FIG. 7 is a circuit diagram of a conventional example of a levitation detector. In this specification, “water” includes “seawater”. Water such as a river, a lake, or the sea contains impurities and is a conductive substance. The levitation detection apparatus 100 includes a comparison unit 101, a smoothing unit 102, a rectification unit 103, a direct current component removal unit 104, an oscillation circuit 105, a variable resistor 106, and an electrode pair 107.

  The electrodes 111 and 112 of the electrode pair 107 are arranged at a predetermined distance. During the period in which the levitation detector 100 is above the water surface, the electrodes 111 and 112 are insulated from each other by air, so that no current flows between the electrodes 111 and 112. On the other hand, during the period when the levitation detection device 100 is submerged, the electrodes 111 and 112 are in a conductive state via water.

  The oscillation circuit 105 is a well-known oscillation circuit equipped with a crystal resonator 115 and an inverter 116, and oscillates and outputs a predetermined oscillation voltage when the electrodes 111-112 become conductive. The oscillation voltage of the oscillation circuit 105 can be adjusted by the variable resistor 106.

  The output voltage of the oscillation circuit 105 is input to the rectifying unit 103 after the DC component is removed by the DC component removing unit 104. The rectifying unit 103 rectifies the alternating current from the direct current component removing unit 104 and outputs the rectified current to the smoothing unit 102.

  The comparison unit 101 includes a comparator 119 and a variable resistor 120. TP1 and TP2 indicate the voltages at the positive phase side and negative phase side input terminals of the comparator 119, respectively. The output voltage of the smoothing unit 102 is input to the positive phase side input terminal of the comparator 119 as TP1. The variable resistor 120 divides the voltage of the DC voltage 124, and supplies the divided voltage as TP2 to the negative phase side input terminal of the comparator 119. TP2 can be adjusted by the variable resistor 120.

  During the period when the ascent detection device 100 is ascending above the water surface, TP1 ≧ TP2, and the output of the comparator 119 is at a high level. On the other hand, during the period when the levitation detection device 100 is submerged, TP1 <TP2, and the output of the comparator 119 is at a low level.

  When the levitation detecting device 100 is used for a long period of time, the electrodes 111 and 112 do not become insulative even if impurities or slimes in the water adhere to the surface and float on the water surface, and the oscillation of the oscillation circuit 105 continues. Thus, the state of TP1 ≧ TP2 is maintained, and a situation in which the ascent of the ascent detection device 100 cannot be accurately detected occurs.

  Further, since the oscillation circuit changes the output voltage with the temperature change during oscillation due to its temperature characteristics, TP1 also changes with the temperature change (see FIG. 8 described later). In order to cope with this, it is necessary to set TP2 appropriately so that the submerged state and the floating state can be accurately detected regardless of the change in water temperature and the adhesion of impurities to the electrodes.

  FIG. 8 is a graph for explaining how to set the threshold value (TP2) in the levitation detection apparatus 100 in the past. A specific procedure for setting TP2 in the conventional levitation detection apparatus 100 will be described with reference to FIG. The following setting procedure is assumed to be performed at sea.

  First, the following steps S131 to S133 are performed in order under normal temperature (eg, seawater temperature = 20 ° C.) conditions.

S131: Power is turned on.

S132: It is confirmed that the oscillation stops in the state where the ascent detection device 100 has floated above the sea surface (corresponding to Pla in FIG. 8). Let TP1 in Pla be Vla. At this time, even if some seawater remains between the electrodes 111-112, TP1 is adjusted by the variable resistor 106 so that the oscillation stops, that is, Vla = 0V.

S133: Confirm that the oscillation circuit 105 oscillates when the electrodes 111 and 112 are submerged (corresponding to Pha in FIG. 8). Also, TP1 in Pha is recorded as Vha.

  Next, the following steps S141 to S143 are performed in order under high temperature (eg, seawater temperature = 30 ° C.) conditions.

S141: Turn on the power.

S142: Confirm that the oscillation circuit 105 oscillates when the electrodes 111 and 112 are submerged in the sea (corresponding to Phb in FIG. 8). Also, TP1 in Phb is measured and recorded as Vhb.

S143: TP1 is measured in a state where the ascent detection device 100 has floated above the sea surface (corresponding to Plb in FIG. 8). Record this measured value Vlb.

  Finally, the following steps S151 to S153 are sequentially performed under a low temperature (eg, seawater temperature = 10 ° C.) condition.

S151: Turn on the power.

S152: It is confirmed that the oscillation circuit 105 oscillates when the electrodes 111 and 112 are submerged in the sea (corresponding to Phc in FIG. 8). In addition, TP1 in Phc is measured and recorded as Vhc.

S143: TP1 is measured in a state where the ascent detection device 100 has floated above the sea surface (corresponding to Plc in FIG. 8). Record this measured value Vlc.

TP2 is set to be an intermediate value between TP1 at the time of oscillation and TP1 at the time of oscillation stop in the water temperature range from low temperature to high temperature.
Japanese Utility Model Publication No. 63-129331

  The problems of the levitation detection apparatus 100 are listed as follows.

(A) TP2 is set so that Vlc <TP2 <Vhb, but the difference between Vlc and Vhb is small, and the adjustment becomes complicated.

(B) Since the difference between TP2 and Vhb is small at high temperatures, it can be detected that the water is submerged despite being ascended, or at low temperatures, the difference between TP2 and Vlc is small. Nevertheless, it is easy to make an error to detect that it is rising.

(C) Since the oscillation of the oscillation circuit 105 starts and stops with the conduction and non-conduction between the electrodes 111 and 112, the oscillation start operation of the oscillation circuit 105 with respect to the conduction and non-conduction between the electrodes 111 and 112 and Delay is likely to occur in the oscillation stop operation. Therefore, for example, the output of the levitation detection device 100 may not be able to follow a very short levitation operation in which a marine life equipped with the levitation detection device 100 rises only for respiration.

(D) Since the oscillation circuit 105 is mounted exclusively for the levitation detection device 100, the mounting area (the number of parts) of the levitation detection device 100 increases, which is a difficulty in downsizing the levitation detection device 100.

  Impurities and slimes adhere to the surfaces of the electrodes 111 and 112 as the service period becomes longer, and in fact, current may flow between the electrodes 111 and 112 regardless of the flying period. This means that the Ph line in FIG. 8 moves downward. As a result, Vhb also decreases, and the above problems (a) and (b) become noticeable.

  An object of the present invention is to provide a water detection device that overcomes each problem and a wireless device equipped with the water detection device.

The water detector of the present invention has the following.
A pair of spaced electrodes,
A potential output means for outputting a potential corresponding to the conductivity between the electrodes of the electrode pair as a detection potential;
An identification means for identifying whether the electrode pair is in water or on the water based on the comparison between the detection potential and the threshold;
Temperature detecting means for detecting the ambient temperature of the electrode pair, and threshold changing means for changing the threshold based on the ambient temperature.

The wireless device of the present invention has the following.
The above-described water detection device, and communication execution means for executing wireless communication during a period when it is determined that the electrode pair is on the water based on the output of the water detection device.

  According to the present invention, the threshold value to be compared with the detection potential corresponding to the conductivity between the electrodes is controlled in relation to the ambient temperature. As a result, the threshold value accurately distinguishes between water and water regardless of the ambient temperature. The value can be adjusted to an appropriate value so that the accuracy of identifying whether the electrode pair is in water or on water can be improved.

  FIG. 1 is a circuit diagram of the levitation detection apparatus 10. The levitation detection device 10 is installed in a wireless device attached to the marine life, for example, in order to monitor the position of the marine life. The levitation detection device 10 is also installed as a predetermined height at a place where the water level increases or decreases, and can be used as a device for detecting whether the installation position is below or above the water surface.

  The electrode pair 11 includes electrodes 12 and 13 that are spaced apart by a predetermined dimension. The electrodes 12 and 13 are connected to electrode connection terminals 16 and 17 through lead wires 14 and 15, respectively.

  The clock pulse signal input terminal 20 receives a clock pulse signal used as a processing timing pulse in the CPU from a controller including a CPU (not shown. The controller is, for example, a controller installed in a wireless device). Supplied. The CPU is always operating, and the clock pulse signal is always generated. The clock pulse signal input terminal 20 is connected to the electrode connection terminal 17 via a resistor 21 and a capacitor 22. The electrode connection terminal 16 is connected to the positive-phase side input terminal of the comparator 26 through the rectifying unit 24 and the smoothing unit 25. The output terminal of the comparator 26 is connected to the comparison result output terminal 29, and the negative phase side input terminal of the comparator 26 is connected to the threshold value input terminal 30.

  The voltages at the positive phase side input terminal and the negative phase side input terminal of the comparator 26 are defined as TP1 and TP2, respectively. The comparison result output terminal 29 is connected to the input terminal of the I / O port of the controller, and the threshold input terminal 30 receives TP2 from the controller via a D / A converter (not shown).

  The temperature sensor 32 is supplied with a voltage from the DC voltage terminal 33 and outputs an analog voltage related to the ambient temperature to the temperature output terminal 34. The temperature output terminal 34 is connected to the input terminal of the controller via an A / D converter (not shown).

  FIG. 2 is a characteristic graph regarding the threshold value (= TP2) of the comparator 26 of the levitation detection apparatus 10. Pla, Pha, Plb, Phb, Plc, and Pha are the same as those described in FIG. Also in FIG. 2, Vla and Vlb are set to 0V.

  TP2 is set on a characteristic line connecting average values of Ph and Pl in the vertical axis direction at each water temperature. That is, at each water temperature, the difference between Ph-TP2 and the difference between Pl-TP2 are substantially the same. In order to cope with the future increase in conductivity between the electrodes 12-13 due to the adhesion of the slime to the surfaces of the electrodes 12, 13 with the increase in the period of use, the bias is initially slightly shifted to the Pl side from the average value. It is also possible to set the value to

  TP2 set as shown in FIG. 2 is stored as a profile in a predetermined storage device. When executing the program (software), the CPU of the controller reads TP2 corresponding to the water temperature detected from the output of the temperature sensor 32 from the profile and supplies a predetermined digital value so that the TP2 is supplied to the threshold input terminal 30. Is output to the D / A converter upstream of the threshold input terminal 30.

  The operation of the levitation detection device 10 will be described.

  The temperature sensor 32 detects the ambient temperature of the levitation detection device 10, that is, the water temperature. As shown in FIG. 2, the controller relates to the temperature detected by the temperature sensor 32 for TP2 supplied to the negative phase side input terminal of the comparator 26 via the D / A converter and the threshold input terminal 30. I have control.

  During the period when the levitation detector 10 is levitated, the electrodes 12-13 are insulated from each other by air, and the electrodes 12-13 are electrically cut off. As a result, both the electrodes 12 and 13 are in an open state, and TP1 is in a low level state, that is, TP1 <TP2, and the output voltage of the comparator 26 is maintained at a low level.

  On the other hand, during the period when the levitation detection device 10 is submerged, water fills between the electrodes 12-13, and the electrical resistance between the electrodes 12-13 is low. As a result, the direct current component of the clock pulse signal having a predetermined frequency at the clock pulse signal input terminal 20 is removed by the capacitor 22, and the remaining alternating current component reaches the electrode connection terminal 16 through the electrode 13 and the electrode 12.

  The alternating current of the electrode connection terminal 16 is sent to the rectification unit 24, and the negative part of the alternating current signal flows to the ground side due to the conduction of the diode 41 of the rectification part 24, and only the positive part passes through the diode 40 of the rectification part 24. To the smoothing unit 25.

  The smoothing unit 25 includes a resistor 43 and a capacitor 44, and the output from the rectifying unit 24 charges the capacitor 44 via the resistor 43 and is smoothed. The voltage of the capacitor 44 is sent to the positive phase side input terminal of the comparator 26 as TP1, and TP1 ≧ TP2. As a result, the comparator 26 produces a high level output voltage.

  Since TP2 is controlled as shown in FIG. 2, the output of the comparator 26 qualifies the submerged state and the floating state regardless of the adhesion of impurities and slime on the surfaces of the electrodes 12 and 13 and the change in water temperature. Will be identified.

  In the conventional levitation detection device 100 (FIG. 7), the oscillation circuit 105 starts and ends operation by switching the power supply state and the power supply stop state in accordance with switching between conduction and non-conduction between the electrodes 111 and 112. The operation start and operation end of the oscillation circuit 105 are delayed with respect to the start and end of conduction between the electrodes 111 and 112. Therefore, the levitation detection device 100 has difficulty in accurately detecting a short levitation period. On the other hand, in the levitation detection apparatus 10, since the clock pulse signal of the CPU is applied to the clock pulse signal input terminal 20 before the conduction between the electrodes 12-13 is started, the electrodes 12-13 are electrically connected. As a result, an alternating current immediately flows between the electrodes 12-13. Thereby, the followability of TP1 with respect to switching between conduction and non-conduction between the electrodes 111-112 is improved.

  In the levitation detection device 10, the mounting of the oscillation circuit 105 in the levitation detection device 100 can be omitted, so that the mounting area (the number of parts) of the levitation detection device 10 increases and the levitation detection device 10 can be downsized.

  When the levitation detection device 10 is installed in a wireless device that monitors the position of marine organisms, the wireless device detects that the antenna of the wireless device is moved to the atmosphere above the sea surface based on the output of the levitation detection device 10. The radio communication operation state is switched only to the exposed period, for example, radio waves from GPS satellites are received, and various information collected about marine life is transmitted to observation satellites or the like. The wireless device is operated by the battery power, but the wireless communication operation time is limited to the period when the antenna is above the sea surface as the marine life rises, so the unnecessary operation time of the wireless device is eliminated. In addition, the time until the battery is out of power can be extended sufficiently.

  FIG. 3 is a circuit diagram of another levitation detector 49. In the levitation detection device 49, the same elements as those in the levitation detection device 10 of FIG. 1 are designated by the same reference numerals, description thereof will be omitted, and only differences will be described.

  The levitation detection device 49 includes an oscillation circuit 50, and uses the oscillation output of the oscillation circuit 50 in place of the clock pulse signal. The oscillation circuit 50 has a well-known configuration and includes an inverter 51, a resistor 52, and a capacitor 53. The oscillation circuit 50 oscillates regardless of conduction or non-conduction between the electrodes 12-13.

  When the levitation detector 49 is in the levitation state, no current flows between the electrodes 12-13, TP1 <TP2, and the output of the comparator 26 is maintained at a low level. On the other hand, when the levitation detecting device 49 is in a submerged state, the AC component of the oscillation output of the oscillation circuit 50 reaches the electrode 12 via the capacitor 22 and the electrode 13. As a result, TP1 ≧ TP2, and the output of the comparator 26 is at a high level.

  In the levitation detection device 49, the oscillation circuit 50 is oscillating before the electrodes 12-13 are in a conductive state. Therefore, an alternating current caused by oscillation of the oscillation circuit 50 is generated between the electrodes 12-13. As soon as conduction starts, it immediately flows between the electrodes 12-13. Thereby, the followability of TP1 with respect to the change in conductivity between the electrodes 12-13 is improved.

  FIG. 4 is a circuit diagram of still another levitation detector 56. In the levitation detection device 56, the same elements as those in the levitation detection device 10 of FIG. 1 are designated by the same reference numerals, description thereof will be omitted, and only differences will be described.

  In the levitation detection device 56, the comparator 26 (FIGS. 1 and 3) is omitted, and the output of the smoothing unit 25 is sent to the detection voltage output unit 57 as the output of the levitation detection device 56. In the ascent detection device 56, the function of the comparator 26 is replaced by execution of a CPU program. That is, the output of the detection voltage output unit 57 is different from the A / D converter (A / D1; hereinafter referred to as “first A / D converter”) present on the controller side of the temperature output terminal 34. The A / D converter (A / D2; hereinafter referred to as “second A / D converter”) is sent to the controller.

  In the controller program, TP2 on the characteristic line in FIG. 2 is read from the profile based on the output of the first A / D converter. Further, TP2 and TP1 calculated based on the output of the second A / D converter are compared by a comparison step on the program. When a result corresponding to TP1 ≧ TP2 is obtained, it is determined that the water is in a submerged state. When a result corresponding to TP1 <TP2 is obtained, it is determined that the vehicle is in a floating state.

  The levitation detector 56 can be further downsized than the levitation detector 10 (FIG. 1) because the comparator 26 (FIG. 1) is omitted.

  FIG. 5 is a block diagram of the water detection device 63. The above-described levitation detection devices 10, 49, and 56 are examples of the water detection device 63. The use of the water detection device 63 is not limited to detecting whether the marine life is submerged or floating when attached to a marine life for ecological observation. The water detection device 63 is installed at a predetermined height. And may be used for detecting whether the installation location is below or above the water surface. The water detection device 63 is installed at a predetermined point, and can also be used for detecting whether or not water is present at the point.

  The water detection device 63 includes an electrode pair 64, a potential output means 65, an identification means 66, a temperature detection means 67, and a threshold value changing means 68.

  The electrodes of the electrode pair 64 are spaced apart. The potential output means 65 outputs a potential corresponding to the conductivity between the electrodes of the electrode pair 64 as a detection potential. The identification unit 66 determines whether the electrode pair 64 is in water or on the water based on the comparison between the detection potential and the threshold value.

  The temperature detection unit 67 detects the ambient temperature of the electrode pair 64. The threshold changing unit 68 changes the threshold based on the ambient temperature. The detection potential and the threshold correspond to TP1 and TP2 in the levitation detection device 10 and the like, respectively.

  An example of the electrode pair 64 is the electrode pair 11 (FIG. 1). Examples of the potential output means 65 are all the elements related to the generation of TP1 in the levitation detection device 10, and are the clock pulse signal input terminal 20, the resistor 21, the capacitor 22, the rectifying unit 24, and the smoothing unit 25.

  An example of the identification unit 66 is the comparator 26 in the levitation detection devices 10 and 49, and is realized by a program in the levitation detection device 56. An example of the temperature detection means 67 is the temperature sensor 32. The example of the threshold value changing means 68 is all elements related to the generation of TP2 in the ascent detection device 10 and the like, and these are realized by a program.

  In the water detection device 63, the threshold value is not fixed and is changed in relation to the temperature. As a result, the threshold value is controlled to a value that can clearly identify the conductive state and the non-conductive state of the electrode pair 64 at each temperature. In this way, the identification unit 66 can accurately determine the conductive state and the non-conductive state of the electrode pair 64 based on the comparison between the threshold value and the detection potential, regardless of the change in the detection potential due to temperature.

  FIG. 6 is a block diagram of a specific example of the potential output means 65. The potential output unit 65 includes a supply unit 71 and an output unit 72. The supply means 71 supplies an alternating current between the electrodes of the electrode pair 64 when the electrode pair 64 is conductive. The output unit 72 uses a potential generated based on an alternating current flowing between the electrodes of the electrode pair 64 as a detection potential.

  For example, the supply unit 71 generates an alternating current based on a clock pulse signal of the CPU. The clock pulse signal input terminal 20 (FIG. 1) of the above-described levitation detection apparatus 10 is supplied with a CPU clock pulse signal, and an AC signal flowing between the electrodes 12-13 is generated from the clock pulse signal.

  Since the clock pulse signal of the CPU is generated before conduction between the electrodes of the electrode pair 64, an alternating current flows quickly between the electrodes of the electrode pair 64 as soon as the electrodes of the electrode pair 64 become conductive. The followability of the detection potential with respect to the start of conduction between the electrodes can be satisfactorily maintained.

  The supply means 71 may also include an oscillation circuit whose output side is connected to one electrode and generates an oscillation signal that is the basis of the alternating current regardless of the conduction between the electrodes of the electrode pair 64. Then, an alternating current flowing between the electrodes of the electrode pair 64 may be acquired from the other electrode side, and a detection potential may be generated based on the acquired current.

  An example of such an oscillating circuit is the oscillating circuit 50 (FIG. 3) of the levitation detector 49 described above. In the levitation detection device 49, the output side of the oscillation circuit 50 is connected to the electrode 13, and TP1 is generated based on the alternating current acquired from the electrode 12 side.

  The oscillation circuit having the output side connected to one of the electrodes can start operation prior to conduction between the electrodes of the electrode pair 64. Therefore, as soon as the electrodes of the electrode pair 64 become conductive, an alternating current is generated between the electrodes of the electrode pair 64. The detection potential can be improved in response to the start of conduction between the electrodes of the electrode pair 64.

  The water detection device 63 is equipped in the wireless device, and can save power of the wireless device. That is, the wireless device includes a water detection device 63 and a communication execution unit that performs wireless communication during a period in which the electrode pair 64 is determined to be on the water based on the output of the water detection device 63.

  Thus, the wireless device operates wirelessly during the period when the antenna is on the water, and stops the wireless operation when the antenna is underwater, so that the power of the battery equipped with the wireless device can be kept long.

  Although various embodiments of the present invention have been described, it is needless to say that the present invention is not limited thereto and can be implemented in various forms within the scope of the gist.

It is a circuit diagram of a levitation detector. It is a characteristic graph about the threshold value of the comparator of a levitation detector. It is a circuit diagram of another levitation detector. It is a circuit diagram of still another levitation detection device. It is a block diagram of a water detection apparatus. It is a block diagram of the specific example of an electric potential output means. It is a circuit diagram of the prior art example of a levitation detector. It is a graph explaining how to set a threshold value in a conventional levitation detection device.

Explanation of symbols

63: Water detection device, 64: Electrode pair, 65: Potential output means, 66: Identification means, 67: Temperature detection means, 68: Threshold change means, 71: Supply means, 72: Output unit

Claims (5)

A pair of spaced electrodes,
A potential output means for outputting a potential corresponding to the conductivity between the electrodes of the electrode pair as a detection potential;
Identification means for identifying whether the electrode pair is in water or on the water based on a comparison between the detection potential and a threshold;
Temperature detecting means for detecting the ambient temperature of the electrode pair; and threshold changing means for changing the threshold based on the ambient temperature;
The water detection apparatus characterized by having.   The potential output means is a supply means for supplying an alternating current between the electrodes of the electrode pair when the electrode pair is conducting, and a potential generated based on the alternating current flowing between the electrodes of the electrode pair as the detection potential. The water detection apparatus according to claim 1, further comprising an output unit.   The water detector according to claim 2, wherein the supply unit generates the alternating current based on a clock pulse signal of a CPU. The supply means includes an oscillation circuit that generates an oscillation signal that is connected to one electrode on the output side and serves as a basis for an alternating current regardless of conduction between the electrodes of the electrode pair,
The water detection apparatus according to claim 2, wherein the output unit acquires an alternating current flowing between the electrodes of the electrode pair from the other electrode side and generates the detection potential based on the acquired current. The water detection apparatus according to any one of claims 1 to 4, and a communication execution means for performing wireless communication during a period in which the electrode pair is determined to be on the water based on an output of the water detection apparatus,
A wireless device characterized by comprising:

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