JPH0932051A - Control device for water supply facility - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a control device for a water supply facility that can perform control with only two wires regardless of the number of electrode rods. [Structure] The water tank 1 has electrode rods 12a to 12 having different lengths.
d and the common electrode rod 12e are inserted. Common electrode 1
2e is connected to the wiring 21 via the connecting portion 15, and the electrode rods 12a to 12d are connected to the impedance device 20 via the connecting portion 15. The impedance device 20 is composed of impedances connected to the electrode rods 12a to 12d, and the parallel connection ends of these impedances are connected to the wiring 2
2 is connected. The controller 23 is provided with a detection impedance connected to the wiring 21 and a power supply connected between this and the wiring 22. Depending on the number of electrode rods inserted in the water in the water tank 1, the impedance device 20
Of the water tank 1 can be detected by detecting this change as a voltage drop in the detection impedance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water supply facility control device for a water supply facility which detects the water level in the water tank and performs a required control.

[0002]

2. Description of the Related Art A control system for a water supply facility detects a water level in a water tank and, in response to this, drives a pump to supply water from the water tank to a water pipe or to output an alarm signal or a display signal. Is. A control device for such a water supply facility is shown in FIG.
This will be described with reference to FIG.

FIG. 13 is a system diagram of a water supply facility using a conventional control device. In this figure, 1 is a water tank, 2 is a water supply pipe from a water main, 3 is a water pipe, 4 is a customer, 5 is a customer 4
It is a water faucet used by. 6 is a pump that sucks water from the discharge pipe of the water tank 1 and supplies it to the pipe 3, 8 is a check valve, and 9 is a check valve.
Is a pressure tank for applying pressure to the water supplied through the pipe 3, and 10 is a pressure switch for detecting the pressure in the pipe 3 (the same as the pressure in the pressure tank 9). The pressure switch 10 is turned on at the first set pressure and turned off at the second set pressure higher than the first set pressure.

Reference numeral 12 denotes an electrode rod group inserted in the water tank 1. The electrode rod group 12 includes electrode rods 12a to 12d and a common electrode rod 12e. The tip of the electrode rod 12a has a full water level L
Up to ₁ , the tip of the electrode rod 12b has a level L ₂
Until (described later), the tip of the electrode rod 12c until slipping prevention level L ₃ (described later), the tip of the electrode rod 12d extends to the water reducing the level L _4. Note that L ₀ indicates the overflow level. The tip of the common electrode rod 12e extends to the vicinity of the bottom of the water tank 1.

Reference numeral 13 is a controller for performing various controls, the details of which will be described later with reference to FIG. Reference numeral 14 is a wiring connected to each electrode rod of the electrode rod group 12, and 15 is a connecting portion between each electrode rod and the wiring 14. Reference numeral 16 denotes a ball tap, which detects when the water level in the water tank 1 has dropped to the water supply start level L _S1 and supplies water to the water tank 1, and when the water level in the water tank 1 reaches the water supply stop level L _S2. When this is detected, the water supply to the water tank 1 is stopped.

FIG. 14 is a block diagram of the controller 13. In this figure, T _a through T _e is the electrode rod 12 a to 12 d,
The terminals are connected to the common electrode rod 12e via the wiring 14 and the connecting portion 15, respectively. 6 is the same pump as shown in FIG. 130 is an AC power supply, 131 is a transformer, 132a, 132d, 132b are rectifiers 133a, 133d, 133b connected between the secondary side of the transformer 131 and the terminals T _a , T _d , T _b. It is a drive circuit. 134C _a coil of the relay, 134S _a relay contact which is switched to a contact side by the excitation of the coils 134C _a, 134C _d is the coil of the relay, 134S _d relay contact is switched to a contact side by the exciting coil 134C _d, 134C _b is a relay coil, 134S
_b1 is the relay contact is switched to a contact side by the excitation of the coil 134C _b. Reference numeral 135 denotes a pump drive circuit, which includes a switch 135S and a coil 13 which are switched and closed by an ON signal of the pressure switch 10 shown in FIG.
It is composed of a relay contact 134S _b2 which is switched to the a contact side by excitation of 4C _b . Reference numeral 136 is an electromagnetic switch that opens and closes the three-phase AC power supply of the pump 6.

Next, the operation of the controller 13 and FIG.
The operation of the water supply facility shown in 3 will be described. If the water level in the water tank 1 is below the water reducing levels L _4, a state where only the common electrode rod 12e is inserted into the water, because there is no connection between the terminal T _e and the other of the terminals, relay contacts 134S _d is shown The water level warning signal is output in the connected state. When the water is supplied from this state and the water level exceeds the water reduction level L ₄ , the electrode rod 12d is inserted into the water, and the common electrode rod 12e and the electrode rod 12d (the terminals T _e and T _c ) become water. Connected via electrical resistance. As a result, the voltage on the secondary side of the transformer 131 is applied to the rectifier 132d,
This is rectified and input to the relay drive circuit 133d,
The relay drive circuit 133d excites the coil 134C _d ,
The relay contact 134S _d is switched to the a contact side, and the output of the water reduction warning signal is stopped.

When the water supply is further continued and the water level exceeds the idling prevention level L ₃ , the electrode rod 12c is put in the water, and the common electrode rod 12e and the electrode rod 12c (terminal T).
_e and the terminal T _c ) are connected via the electrical resistance of water.
However, since the relay contact 134S _b1 is not switched, the state does not change. Is continued water supply, the water level exceeds the idling prevention cancellation level L _2, a state in which the electrode rod 12b is inserted into the water, the common electrode rod 12e and the electrode rod 12b (terminal T _e and the terminal T _b) Togamizu Connected via electrical resistance. As a result, the voltage on the secondary side of the transformer 131 is applied to the rectifier 132b, rectified and input to the relay drive circuit 133b, and the relay drive circuit 133b.
Will energize the coil 134C _b, the relay contact 134S _b1,
Each of 134S _b2 is switched to the a contact side. By switching the relay contact 134S _b2 , one phase of the three-phase power source is connected to the switch 135S.

When the water supply is further continued and the water level exceeds the full water level L ₁ , the electrode rod 12a is inserted in the water, and the common electrode rod 12e and the electrode rod 12a (terminal T _e and terminal T _a ) are separated from each other. It is connected through the electrical resistance of water. Thus, the rectifier 132a voltage on the secondary side of the transformer 131 is applied to, is rectified is inputted to a relay drive circuit 133a, the relay drive circuit 133a will energize the coils 134C _a, the relay contact 134S _a is a contact It is switched to the side and the full water alarm signal is output.

In this state, when water is used in the faucet 5 of the customer 4 and the pressure in the pipe 3 decreases below a predetermined pressure, the pressure switch 10 is turned on, and the switch 13 is activated by the signal.
5S closes. As a result, the electromagnetic contactor 136 is operated via the relay contact 134S _b2 that is already closed and the switch 135S, the pump 6 is driven, and the water in the water tank 1 is supplied to the pipe 3.

On the other hand, when the water level in the water tank 1 drops below the full water level L ₁ , the connection between the common electrode rod 12e and the electrode rod 12a via water is cut off, the relay coil 134C _a becomes non-excited, and the relay contact 134S. _a is reversed and returned to the original state, and the full water alarm signal is no longer output. Furthermore, when the water level drops below the level I _{2 for} preventing slipping, the common electrode rod 1
2e and electrode rod 12b are disconnected, but relay contact 1
Since 34S _b1 is switched, the coil 134C _b remains excited via the electrode rod 12c, and the state does not change. Further water level connection via water between the common electrode rod 12e and the electrode rod 12c and drops below the idling prevention level L ₃ is cut off, the relay coil 134C _b is deenergized, the relay contacts 134S _b1 and relay contacts 134S _b2 is inverted Then, even if the pressure of the pipe 3 is lowered in this state, the pump 6 is not driven because the relay contact 134S _b2 is cut off. Further water is cut off the connection via the water between the common electrode rod 12e and the electrode rod 12d and falls below the water reducing level L _4, relay coil 134C _d is deenergized, the return to the original relay contacts 134S _d is inverted, A low water warning signal is output.

During the above operation, the idling prevention level L ₃ is such that when the water tank 1 is at a lower level as described above, the water in the water tank 1 runs out when water is supplied by the pump 6.
The pump 6 is prevented from idling and the sliding portion thereof is prevented from seizing. The idling prevention release level L ₂ is the water reduction level L.
It is intended to prevent the pump 6 from supplying water to the pipe 3 when water is being supplied from ₄ to the water tank 1. The full water alarm signal and the low water alarm signal are used as a display on the display, an alarm by the alarm, or a notification signal to an administrator who manages this water supply facility at a remote location.

[0013]

The above-mentioned water supply facility is installed in a high-rise building (building), and usually the water tank 1 is arranged underground in order to effectively use the floor area of the building. Further, the controller 13 is arranged in the machine room or the manager's room of the building. For this reason, the water tank 1 and the controller 13 are located far away from each other, and the larger the building, the greater the distance between the two. By the way, in the above conventional water supply facility, the five wires 14 are connected to the water tank 1 and the controller 13.
Since a long distance must be provided between them, an error in the connection between them is likely to occur, and a wiring accident such as a disconnection is likely to occur in proportion to the number of wirings. In addition, when adding more electrode rods to a facility equipped with only common electrode rods and electrode rods filled and filled with water, there is a problem in that long-distance wiring must be performed by the number of electrode rods to be added. there were.

An object of the present invention is to solve the above-mentioned problems in the prior art and to provide a controller for a water supply facility that can perform control with only two wirings regardless of the number of electrode rods. .

[0015]

In order to achieve the above object, the present invention relates to a water tank, a common electrode rod inserted up to the vicinity of the bottom of the water tank, and a water level in the water tank inserted into the water tank. Accordingly, in a water supply facility comprising the common electrode rod and an electrode rod group composed of a plurality of other electrode rods each having a different length connected through water, one end of each of the other electrode rods is provided. Connected to each impedance of a predetermined value, a first wiring in which the other ends of these impedances are connected in parallel, a second wiring connected to the common electrode rod, the first wiring and the first wiring. An AC power supply and a detection impedance connected in series between the wiring 2 and
Water level detection means for detecting the water level based on the output of the detection impedance that changes according to the water level in the water tank is provided.

[0016]

The connection between the common electrode rod and the other electrode rods is determined by the water level in the water tank. Therefore, the value of the composite impedance by each impedance connected to another electrode rod changes according to the connection of the other electrode rod connected according to the water level in the water tank. The detection impedance detects a voltage or current determined by the value of the combined impedance, and each water level in the water tank is detected based on the detected voltage or current. The wiring between the water tank and the control device is only two, that is, the first wiring and the second wiring, and even if the electrode rod is added, the impedance for this is added and the wiring does not increase.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. FIG. 1 is a system diagram of a water supply facility using a control device according to an embodiment of the present invention. In this figure, parts that are the same as or equivalent to the parts shown in FIG. 20 is an impedance device, 21 and 22 are wirings, 2
3 is a controller. The other parts are the same as those shown in FIG. Here, the impedance device 20 will be described with reference to FIG.

FIG. 2 shows the impedance device 20 shown in FIG.
It is a block diagram of. In this figure, 20a is an electrode rod 12a.
Impedance of value Z ₁ connected to the electrode rod, 20b is impedance of value Z ₂ connected to the electrode rod 12b, 20c is impedance of value Z ₃ connected to the electrode rod 12c, 2
0d is the impedance of the value Z ₄ connected to the electrode rod 12d, and each is connected to each electrode rod via the connection portion 15. T _22O is an output terminal of the impedance device 20, to which the other _ends of the impedances 20a to 20d are connected, and the wiring 22 shown in FIG. 1 is connected to this terminal T _22O . Hereinafter, these impedances Z _{1 to} Z
₄ of the values with reference to FIGS. 3 and 4 will be described.

FIG. 3 is an explanatory diagram of the value of each impedance shown in FIG. In this figure, 12a to 12d and 12e are electrode rods and common electrode rods shown in FIG. 1, 20a to 20d are impedances shown in FIG. 2, 230, 231, and 232 are AC power sources and transformers provided in a controller 23 described later. And impedance for detection. The detection impedance 232 is connected to the common electrode rod 12e via the wiring 21. When any of the electrode rods 12a to 12d is connected to the common electrode rod 12e via water, an alternating current passes through the electrode rod in the connected state, its impedance, the detection impedance 232, and the common electrode rod 12e. flow,
A voltage drop occurs in the detection impedance 232.
The magnitude of this voltage drop is related to the number of electrode rods electrically connected in parallel according to each water level in the water tank 1. In this embodiment, the detection impedance 232 is set so that the change in the voltage drop changes in proportion to the number of electrode rods connected in parallel.
And the size of the impedances 20a to 20d are set.

In order to set the magnitude of each impedance as described above, the longest electrode rod 12 after the common electrode rod 12e.
The value of the impedance 20d connected to d is set to the value Z as shown in FIG.
The value of 0c is Z / x and the value of impedance 20b is Z / x.
y, the value of the impedance 20a is Z / z, and the value of the detection impedance 232 is αZ.

Here, the water level in the water tank rises and each electrode rod 1
The magnitudes of the voltage drops occurring in the detection impedance 232 when 2d to 12a are sequentially connected to the common electrode rod 12e via water are v ₁ , v ₂ , v ₃ , and v ₄ , respectively,
Letting the voltage of the AC power supply 230 be e, the voltage drops v ₁ , v
₂ , v ₃ and v ₄ are respectively represented by the following equations. v ₁ / e = α / (1 + α) ……………… (1) v ₂ / e = α (1 + x) / [1 + α (1 + x)] ……… (2) v ₃ / e = α ( 1 + x + y) / [1 + α (1 + x + y)] ... (3) v ₄ / e = α (1 + x + y + z) / [1 + α (1 + x + y + z)] (4) By the way, in the actual control, the above voltage drops v _{1 to} v _Four
The widths of mutual changes are made equal, that is, v ₂ = 2v ₁ , v
It is desirable that ₃ = 3v ₁ and v ₄ = 4v ₁ . As a condition therefor, the relationship between the values x, y, z and the value α may be set as in the following equation. x = (1 + α) / (1-α) ………… (5) y = (1 + α) / [(1-α) ・ (1-2α)] ………… (6) z = (1 + α) / [(1-2α) · (1-3α)] (7) From the above equations (5), (6), and (7), the impedance value Z ₀ of the detection impedance 232 and the impedance device 20 If the impedance values Z _{1 to} Z ₄ are selected according to the following equation, the variation range of the voltage drop when the electrode rods are sequentially connected to the common electrode rod 12e through water is represented by the value v.
Can be equal to ₁ . Z ₀ = αZ (8) Z ₁ = (1-2α) (1-3α) Z / (1 + α) (9) Z ₂ = (1-α) (1-2α ) Z / (1 + α) ………… (10) Z ₃ = (1-α) Z / (1 + α) ………… (11) Z ₄ = Z ……………… (12) The values of the impedances Z _{0 to} Z ₄ are uniquely determined by setting the above values Z and α. Normally, the water resistance of tap water is several tens of kΩ when the tip of the electrode rod begins to come into contact with water, but when the electrode rod is inserted about 1 cm,
It becomes about 100 Ω and decreases exponentially thereafter. Therefore, if the above-mentioned value Z is selected to be several kΩ, it will be a sufficiently large value in comparison with fluctuations in water resistance and changes in the magnitude of water resistance due to changes in water quality and temperature in the water tank, and the control will not be affected by these fluctuations and changes. It will not be affected. Further, the coefficient α is expressed by the equation (9), (1
It may be selected so that the values Z ₁ , Z ₂ , and Z _{3 in the} expressions 0) and (11) do not become negative values.

FIG. 4 shows the coefficient α and the impedance Z ₄ (=
Z) for each impedance Z ₀ , Z ₁ , Z ₂ , Z ₃
2 is a graph showing the relationship with the ratio of, where the horizontal axis represents the coefficient α and the vertical axis represents the impedance ratio. For example, as shown in the figure, when the coefficient α is selected to be 0.2, Z ₀ /Z=0.2, Z
_{1 /Z=0.2, Z 2 /Z=0.4, Z} 3 /Z=0.667, become.

Next, the structure of the controller 23 shown in FIG. 1 will be described. FIG. 5 is a block diagram of the controller 23 according to the first embodiment of the present invention. In this figure, T _21i is an input terminal to which the wiring 21 (to which the common electrode rod 12e is connected) shown in FIG. 1 is connected, and T _22i is wiring 22 (to which the impedance device 20 is connected) shown in FIG. Exist)
Is an input terminal to which is connected. 230 is an AC power supply, 23
Reference numeral 1 is a transformer and 232 is a detection impedance, which are the same as those shown in FIG. 233 is a voltage determination circuit connected between both ends of the secondary side of the transformer 231. r _{1 to} r ₅ are also voltage dividing resistors connected between both ends of the secondary side of the transformer 231, and by these voltage dividing resistors,
A reference voltage for the voltage drop of each electrode rod that occurs in the detection impedance 232 when each electrode rod is connected to the common electrode rod 12e via water is set.

234a to 234d are the electrode rods 12a to 1
2d is a relay drive circuit provided corresponding to the voltage generated in the detection impedance 232 and the corresponding reference voltage set by the voltage dividing resistors r _{1 to} r ₅ for each relay drive circuit. The output signal of the determination circuit 233 is input. 235C _{a to} 235C _d are relay coils, 2
35S _{a to} 235S _d are corresponding coils 235C _a to 2
35C _d is a relay contact that is switched when energized. Incidentally, 13 denotes a controller of the same configuration as that shown in FIGS. 13 and _{14, T a, T b,} T c, T
_d is the same input terminal as shown in FIG.

The operation of this embodiment will be described below with reference to FIGS. First, the values α and Z in the equations (8) to (12) are set to appropriate values, and the impedances 20a to 20d of the impedance device 20 and the values Z _{0 to} Z ₄ of the detection impedance 232 are set to (8) to. (1
2) Set according to the formula. The water level in the aquarium 1 is L
When it is less than ₄ , none of the electrode rods 12a to 12d has a connection to the common electrode rod 12e through water, so that the circuit of the detection impedance 232 is cut off and no voltage is detected. In this case, the relay drive circuits 234a-23
No output from 4d, coils 235C _{a to} 235C _d
Is non-excited, the relay contacts 235S _{a to} 235S _d are not switched, the power supply in the controller 13 and the rectifier circuits 132a, 132d, 132b (see FIG. 14) are cut off, and a water reduction warning signal is output.

When the water exceeds the reduction level L ₄ , the electrode rod 1
Since 2d and the common electrode rod 12e are connected via water, the impedance 2 of the electrode rod 12d is connected in series with the detection impedance 232 in the secondary side circuit of the transformer 231.
0d is inserted, and a detection voltage is generated in the detection impedance 232. FIG. 6 is a waveform diagram showing an example of the detection voltage generated in the detection impedance 232. The horizontal axis represents time and the vertical axis represents voltage. In FIG. 6, E is a transformer 231.
The voltage on the secondary side of E _d , E _d , indicates the detection voltage of the detection impedance 232 when the impedance 20 d is inserted. The voltage waveforms E _{a to} E _c will be described later. This detection voltage E _d is input to each of the relay drive circuits 234a to 234d. On the other hand, each of the relay drive circuits 234a to 234
The corresponding reference voltage set by the voltage dividing resistors r _{1 to} r ₅ is always input to d. Further, the signals of the voltage determination circuit 233 are also input to each of the relay drive circuits 234a to 234d as shown in FIG.

FIG. 7 is a diagram for explaining the output signal of the voltage determination circuit 233, in which the horizontal axis represents time and the vertical axis represents voltage. E is the same voltage on the secondary side of the transformer 231 as shown in FIG. The voltage determination circuit 233 is the transformer 23.
While the voltage E on the secondary side of 1 is input, the signal e ₂₃₃ having a constant level is output while the voltage E is equal to or higher than the value E ₀ . In the illustrated case, the output period of this signal e ₂₃₃ is the time t ₁
~ T ₂ . As described above, the signal e ₂₃₃ is input to each of the relay drive circuits 234a to 234d.

The relay drive circuits 234a to 234d are
Only when the signal e ₂₃₃ is input, the detection voltage detected by the detection impedance 232 is compared with the reference voltage, and when the detection voltage exceeds the reference voltage, the exciting current is output to the coil of the corresponding relay. To do. The detection voltage E _d compared with the reference voltage in this way is shown in FIG. In FIG. 8, the horizontal axis represents time and the vertical axis represents voltage. E is the same voltage on the secondary side of the transformer 231 as shown in FIG. As shown in the figure, the detected voltages E _d to be compared are the times t _{1 to} t _2.
Is the detection voltage E _d shown in FIG. Will be described later detects the voltage E _a to E _c.

When the detection voltage E _d is detected as described above, this detection voltage E _d is detected by each relay drive circuit 234a.
~ 234d is compared with each reference voltage, the relay drive circuit 2
Only in 34d, it is judged that the reference voltage is exceeded, and the exciting current is output to the coil 235C _d . As a result, the relay contact 235S _d is switched, the terminal T _d and the terminal T _{e of} the controller 13 are connected, the relay contact 134S _a (see FIG. 14) of the controller 13 is switched, and the output of the water reduction warning signal is stopped. It

Similarly, when the water exceeds the idling prevention level L ₃ , the impedance of the impedance device 20 20d, 2
0c is a state of being inserted in parallel, the detection voltage E _c shown in FIG. 6 is detected at the detection impedance 232, which are compared with each relay driving circuit 234a~234d as a detection voltage E _c shown in FIG. 8, as a result , The excitation current is output from the relay drive circuits 234c and 234d,
Between the terminals T _e and T _{c of the} controller 13 and the terminal T
_e and T _d are connected. When the water exceeds the idling prevention release level L ₂ , the impedances 20d, 20c and 20b of the impedance device 20 are inserted in parallel, and the detection voltage E _b shown in FIG. are compared with each relay driving circuit 234a~234d as a detection voltage E _b shown in FIG. 8, the relay driving circuit 234b, 234c, the exciting current is output from 234d, the terminal T _e of the controller 13, between T _c, the terminal T _e, The T _d and the terminals T _e and T _b are connected. Furthermore, when the water exceeds the full level L ₁ , the impedances 20d, 20c, 20 of the impedance device 20 are
b and 20a are inserted in parallel, the detection voltage E _a shown in FIG. 6 is detected by the detection impedance 232, and this is compared as the detection voltage E _a shown in FIG. 8 in each of the relay drive circuits 234a to 234d, Relay drive circuit 2
Exciting currents are output from 34a, 234b, 234c, and 234d, and the terminal T _{e of the} controller 13 and all other terminals are connected. The operation after connecting the terminals of the controller 13 is the same as the operation of the conventional apparatus.

FIG. 9 is a diagram showing an example of changes in each detected voltage with respect to the water level, in which the horizontal axis represents the water level and the vertical axis represents the detection level. As described above, the influence of water resistance appears at the start of contact between the electrode rod and water. Thus, for example (while the water level rises to a depth L ₃₀₎ electrode rod 12c at the level L ₃ may be inserted into the water, while the tip of the electrode rod 12c is inserted to a depth L _30, the detection level is given Does not reach the value of. But,
When the depth exceeds L ₃₀ , the detection level becomes a predetermined value. From FIG. 9, it can be seen that the fluctuation range of each detection level is constant (0.167 in the illustrated case).

As described above, in this embodiment, the impedance is connected to each electrode rod and the common electrode rod, and the detection impedance is provided to the controller, and each electrode rod is connected to the common electrode rod through water. The change in the combined impedance at that time is detected as a change in the voltage drop that occurs in the detection impedance, and this is compared with the reference voltage to detect the water level corresponding to each electrode rod. Regardless of whether or not the wiring is controlled by two wires, it is possible to prevent an error in the connection between the water tank and the controller, reduce wiring accidents such as disconnection, and further Wiring for new installation can be eliminated.

Since the values of the impedances connected to the electrode rods, the impedances connected to the common electrode rod, and the detection impedance are selected as described above,
The change width of the detection voltage can be made equal, and control can be performed easily and reliably. Furthermore, the determination circuit performs the comparison with the reference voltage when the detected voltage has a large value, so that the comparison can be performed accurately, and thus the detection can be performed accurately.

FIG. 10 is a block diagram of a controller according to the second embodiment of the present invention. In this figure, the same or equivalent parts as those shown in FIG. Reference numeral 24 represents the controller of this embodiment. The controller 23 shown in FIG. 5 uses the conventional controller 13, whereas the controller 24 does not. Two
4C is a relay coil that is excited when the relay contact 235S _C is switched, 24S ₁ is a relay contact that is switched by excitation of the coil 24C, and 241 is a pump drive circuit. This pump drive circuit 241 has a coil 24C.
Is constituted by a relay contact 24S _{2 which is} switched when excited, and a switch 241S which is switched by an ON signal of the pressure switch 10. An electromagnetic switch 242 opens and closes the three-phase AC power source of the pump 6.

Unlike the controller 23 shown in FIG. 5, the controller 24 has relay contacts 235S _a and 235S _b.
Is used to directly control the full water alarm signal and the low water alarm signal, and the pump drive circuit 241 is also directly controlled without using the conventional controller 13. That is, the coil 24C is energized when the relay drive circuit 234c is excited coil 235C _c, but switches the relay contact 24S ₁ by the excitation, the relay driving circuit 234d is switched to relay contacts 235S _d in this case, the coil 24
C is also excited by the relay drive circuit 234d.

Therefore, even when the relay circuit 234d excites the coil 235C _d at the time when the water level in the water tank 1 rises from the reduced water level L ₄ and exceeds the idling prevention level L ₃ , the relay contact 24S ₁ remains open. The coil 24C is not excited, but after the water level once exceeds the idling prevention release level L ₂ (after the coil 24C is once energized), the water level is idling even if the water level becomes less than the idling prevention release level L _2. As long as it is between the prevention release level L ₂ and the idling prevention level L ₃ , the coil 24C is excited via the relay contact 235S _d and the relay contact 24S ₁ , so that the pump 6 can be operated. With this configuration, the control 24 of the present embodiment can omit the use of the conventional control 13 and can simplify the configuration.

FIG. 11 is a block diagram of a controller according to the third embodiment of the present invention. In this figure, the same or equivalent parts as those shown in FIG. Reference numeral 25 denotes the controller of this embodiment. The controller 25 is configured by using a microcomputer. 253 is an A / D converter for converting the secondary voltage of the transformer 231 into a digital value, 254 is an A / D converter for converting the detection voltage of the detection impedance into a digital value, and 255 is a central processing unit of a microcomputer. (CPU) 256a, 256b, 256c are output ports of the microcomputer, respectively. 257 is a relay drive circuit, and 258C is a relay coil excited by the relay drive circuit 257. A pump drive circuit 259 is composed of a relay contact 258S that is switched when the coil 258C is excited and a switch 259S that is switched by an ON signal of the pressure switch 10. An electromagnetic switch 260 opens and closes the three-phase AC power supply of the pump 6.

The operation of the controller 25 will be described with reference to the flowchart shown in FIG. First, the reference voltage of each water level (each electrode rod) to be compared with the detection voltage detected by the detection impedance 232, that is, the resistors r ₁ , r ₂ , r ₃ , r ₄ , r ₅ shown in FIG. A reference voltage corresponding to the reference voltage determined by is stored in a memory (not shown) of the microcomputer. Next, the CPU 255 takes in the values of the A / D converters 253 and 254 (step S ₁ shown in FIG. 12). Next, the CPU 255 compares the power supply voltage (secondary side voltage of the transformer 231) taken from the A / D converter 253 with the determination start voltage (voltage E ₀ shown in FIG. 7) (step S ₂ ). When it is determined that the power supply voltage is equal to or higher than the determination start voltage, the CPU 255 compares the detection voltage fetched from the A / D converter 254 with the reference voltage stored in the memory (step S ₃ ), and the water tank 1. Determine the water level within 1, that is, which electrode rod is under water. And the CPU 255
Sets the output signal (determination signal) according to the water level (procedure S
₄ ), output ports 256a-2 corresponding to this determination signal
Outputs a signal to 56c (Step S _5). If it is determined in step S ₂ that the power supply voltage is less than the determination start voltage, CP
U255 outputs a signal of the same signal set by the processing of steps S ₄ to the previous to the corresponding output port (Step S _5).

When a signal is output to the output port 256a, it becomes a full signal, when it is output to the output port 256b it becomes a water reduction signal, and when it is output to the output port 256c it becomes a drive signal for the relay drive circuit 257. When a signal is output to the relay drive circuit 257, the coil 258C is excited, the pump drive circuit 259 enters a standby state, and when the pressure switch 10 outputs an ON signal, the pump 6 is driven. By using a microcomputer as the control 25 of this embodiment, the configuration can be further simplified as compared with the controller 24.

In the description of each of the above-mentioned embodiments, the water tank 1 is arranged underground and the water in the water tank 1 is supplied to the pipe 3 by the pump 6, and the water pressure in the pipe 3 is adjusted to a predetermined pressure in the pressure tank 9. The example of applying the control device to the water supply facility of the retained type has been described. However, the control device of the present invention is not applied only to the water supply facility of such a system, and is a water supply facility that detects the level of the water tank and performs the required control based on the detected level. It can be applied to any water supply facility. This is clear from the fact that the present invention detects the level in the water tank according to the electrode rod provided in the water tank.

For example, there is a system in which water tanks are provided in the basement and on the roof of the building respectively, and water is temporarily stored in the underground water tank, and the stored water is pumped to the water tank on the roof by a pump if necessary. It is also applicable to water supply facilities (no pressure tanks and pressure switches are used in this scheme).
In this case, the electrode rod group 1 according to the above-mentioned embodiment is added to the roof water tank.
2, a full water alarm and a low water alarm are output by the same means as in the above embodiment, and the pumping pump is driven. The pumping pump is driven, for example, when the level of the roof water tank becomes less than the level L ₃ in the above embodiment, and when the level reaches L ₂ , the driving is stopped.

Further, in the description of the above-mentioned embodiment, an example in which the change widths of the respective detection voltages are made the same has been explained, but it is not always necessary to make them the same, and even if the change widths of the voltages are different, the electrode bars of the electrode rods are different. It suffices that the length relationship and the detection voltage magnitude relationship (the longer the electrode rod, the smaller the corresponding detection voltage) match.

[0043]

As described above, according to the present invention, impedance is connected to each of the other electrode rods and the common electrode rod, and the detection impedance is provided in the controller, and the other electrode rod is the common electrode rod. Since the change in the combined impedance when connected to water via water is detected as the change in the voltage drop that occurs in the detection impedance, and the water level is detected based on this voltage drop, the number of other electrode rods Regardless of the above, control can be performed with two wires, which can prevent an error in the connection between the aquarium and the controller, reduce wiring accidents such as disconnection, and further Wiring can be eliminated when a new rod is installed.

[Brief description of drawings]

FIG. 1 is a system diagram of a water supply facility using a control device according to an embodiment of the present invention.

FIG. 2 is a block diagram of the impedance device shown in FIG.

FIG. 3 is an explanatory diagram of the value of each impedance shown in FIG.

FIG. 4 is a diagram showing the relationship between the impedance coefficient α shown in FIG. 3 and the ratio of each impedance to the reference impedance.

FIG. 5 is a block diagram of a control device according to the first embodiment of the present invention.

FIG. 6 is a waveform diagram illustrating a detection voltage.

7 is a diagram illustrating an output signal of the determination circuit shown in FIG.

FIG. 8 is a diagram illustrating a detection voltage compared with a reference voltage.

FIG. 9 is a diagram showing an example of changes in each detection voltage with respect to the water level.

FIG. 10 is a block diagram of a control device according to a second embodiment of the present invention.

FIG. 11 is a block diagram of a control device according to a third embodiment of the present invention.

FIG. 12 is a flowchart illustrating an operation of the control device shown in FIG.

FIG. 13 is a system diagram of a water supply facility using a conventional control device.

FIG. 14 is a block diagram of the controller shown in FIG.

[Explanation of symbols]

 1 Water Tank 3 Piping 4 Customer 6 Pump 9 Pressure Tank 10 Pressure Switch 12 Electrode Rod Group 15 Connection 20 Impedance Device 21, 22 Wiring

Claims (5)

[Claims] 1. A water tank, a common electrode rod inserted up to near the bottom of the water tank, and a common electrode rod inserted into the water tank and selectively connected to the common electrode rod through water according to the water level in the water tank. In a water supply facility provided with an electrode rod group consisting of a plurality of other electrode rods each having a different length, each impedance of a predetermined value with one end connected to each of the other electrode rods, and the impedance of each of these impedances. A first wire having the other end connected in parallel, a second wire connected to the common electrode rod, and an AC power supply and detection connected in series between the first wire and the second wire. Impedance for
A control device for a water supply facility, comprising: a water level detection unit that detects the water level based on the output of the detection impedance that changes according to the water level in the water tank. 2. The impedance according to claim 1, wherein each impedance has a reference value as an impedance connected to an electrode rod having a length next to the common electrode rod, and the other impedances have predetermined different coefficients with respect to the reference value. A control device for a water supply facility, which is set to a multiplied value. 3. The water level detection means according to claim 1 or 2, wherein each set voltage corresponding to each of the electrode rods,
Water supply characterized by comprising a comparison means for comparing each of these set voltages with the output of the detection impedance and a signal output means for outputting a predetermined signal according to the comparison result of the comparison means. Facility control equipment. 4. The comparison device according to claim 3, wherein the comparison is performed within a predetermined period centered on at least one of a maximum value and a minimum value within one cycle of the AC power supply. Control equipment for water supply facilities. 5. The water level detected by the water level detecting means according to claim 1, wherein the water level is a full water level, a reduced water level,
And at least one other water level.