JPH08134968A - Control device for water feed device of building - Google Patents

Abstract

PURPOSE: To improve accuracy of the previw of failure of a water feed system by detecting electric conductivity between electrodes for detecting a water level lower than a fixed level at every fixed cycle by direct current voltage, and detecting continuity/non-continuity oppositely to the fixed period by alternating current voltage. CONSTITUTION: A microcomputer 30 outputs a changeover signal to a changeover switch 20 at a fixed cycle. In this case in which a changeover signal exists, the terminals 21, 23 of the changeover switch 20 are connected together so as to impress the voltage of a direct current power source 44 between electrodes 16, 18. The output signals of detectors 25, 24 of voltage and current are taken in through a A/D converter 28. Direct current voltage is impressed only in a short time so as to make the signal taken in the microcomputer 30 to be a direct current quantity, and electric conductivity is computed at high speed and in high accuracy. Hereby, a failure is foreknown while specifying a feed water supply system, and the improvement plan can be beforehand made by obtaining warning output in the stage of deteriorated performance before the custmary detecting operation for a failure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water supply system for a building, and more particularly to a control system for a water supply system for a building used for predicting deterioration of equipment.

[0002]

2. Description of the Related Art For the purpose of safe and hygienic water supply of a building water supply facility, an electrode rod is provided in a water receiving tank to detect fullness and low water, and an alarm panel notifying that a failure has occurred in a valve or a pump is provided. It is provided. In this case, since an alarm is issued after a failure occurs, there is a problem that it takes time to restore the failed equipment. Therefore, an apparatus having a function of predicting equipment failure has been proposed. Further, as a method of energizing between the electrode rods, direct current or alternating current is considered, but alternating current has been used because of the problem of life due to electrolytic corrosion of the electrode rods.

[0003]

However, this requires a sensor for predicting equipment failure, and it is difficult to install the sensor in the equipment of an existing building and what kind of sensor is to be provided. It is necessary to have knowledge of sensor signals and prediction of failure or experience of a manager, and there is a problem that the system is complicated and difficult to apply. Also, when measuring the conductivity between the electrode rods,
In order to detect at high speed using an AC voltage, it is necessary to have a frequency higher than the commercial power supply frequency, and a high-speed A / D converter is required to capture such a high-frequency signal into a microcomputer. There is a problem.

The object of the present invention is to solve the above-mentioned problems of the prior art and to predict the failure of the water supply system in the existing building without adding a new sensor to the existing electrode rod. It is to provide a control device for a water supply device.

[0005]

In order to achieve the above object, in a controller for a water supply system of a building, which monitors the water level of a water tank and controls a pump by a plurality of electrode rods having different lengths, a constant water tank is defined. A means for detecting the conductivity between the common electrode rod paired with the electrode rod for detecting a low water level with respect to the water level position at a predetermined cycle using a DC voltage, and conduction and non-conduction of the electrode rod. Means for detecting the use of an AC voltage in a reciprocal relationship with the predetermined cycle, and means for predicting the deterioration of the water supply equipment based on the output of the means for detecting the conductivity between the electrode rods and outputting an alarm. Is provided.

[0006]

As described above, the control device for the water supply system of the building according to the present invention has the conductivity between the common electrode rod paired with the electrode rod for detecting the low water level relative to the constant water level position of the existing water tank. It is possible to alternately switch between a means for detecting at a predetermined cycle using a DC voltage and a means for detecting conduction and non-conduction of the electrode rod by using an AC voltage in a reciprocal relationship with the predetermined cycle. Therefore, it is possible to continuously detect the change in the water level from the change in the electrical conductivity between the electrode rods by utilizing the function of the conventional alarm panel that informs that a failure has occurred in the valve or the pump. Further, since the conductivity between the electrode rods is performed by using the DC voltage, the conductivity is small compared with the number of data of the AC voltage taken in, and high-speed and highly accurate detection can be performed. From this continuous water level, the change in the fluctuation range of the water level during constant water level operation of the valve is detected, and when the upper limit of the water level in the fluctuation range tends to increase, it is judged that the water stopping capacity of the valve has deteriorated. To issue a failure prediction signal. On the contrary, when the lower limit of the water level in the fluctuation range is decreasing, it is judged that the water supply capacity of the valve is deteriorated, that is, the auxiliary valve (flow valve) that controls the water supply of the valve is deteriorated and failure prediction is performed. Signal a signal.

Further, it is judged that the pumping capacity of the pump has deteriorated from the decreasing tendency of the water level change time from the upper limit of the constant water level to the lower limit of the electrode rod, and a failure prediction signal is issued. In this way, it is possible to predict a failure of the water supply system equipment by using the existing electrode rod in the existing building without providing a special sensor.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.

FIG. 2 is a schematic block diagram showing a controller of a water supply system for a building according to an embodiment of the present invention.

The building water supply system comprises a water receiving tank 2 and an elevated water tank 3 installed in a building 1. A water supply pipe 9 for supplying water is connected to the water receiving tank 2 through a constant water level valve 8, while
A water supply pipe 6 and a plurality of water taps 7 arranged in the building 1 are connected to the elevated water tank 3, and the water receiving tank 2 and the elevated water tank 3 are connected by a pipe 4 via a pump 5. Inside the water receiving tank 2, a sub valve 12 of a constant water level valve 8 whose opening and closing is controlled by a ball tap 11 and an electrode rod 13 for electrically detecting the water level of the water receiving tank 2 from electrical continuity and non-conduction are provided. On the other hand, in the elevated water tank 3, an electrode rod 14 for electrically detecting the water level of the elevated water tank 3 from electrical continuity and non-conduction is provided. The signals of the electrode rods 13 and 14 are input to the control device 10, and the control device 10 is configured to control the pump 5 based on this signal.

FIG. 1 is a block diagram of a portion of the above-described control device 10 relating to the present invention.

The control device 10 comprises a first control device 26 and a second control device 27. First control device 26
Receives the output voltage of the AC transformer 15 as an input, converts the signal of the electrode rod 13 for detecting the water level from electrically conducting and non-conducting into a DC signal through the rectifiers 34, 35, 36, and converts this signal. It is composed of amplifiers 37, 38 and 39 which amplify and output to the output terminals 40, 41 and 42. The capacitor 33 is provided in addition to the rectifier 36 so that the output voltage of the rectifiers 34 and 35 not connected to the changeover switch 20 becomes twice or more the holding time. This allows the switch 20 to maintain a sufficient output voltage for the period in which the input of the rectifier 36 is released. The second control device 27 includes a changeover switch 20 and a DC power source 44 applied to the electrode rods 16 and 18.
A for taking in the signals of the voltage detector 25 for measuring this DC voltage and the current detector 24 for measuring the DC current flowing between these electrode rods to the microcomputer 30.
/ D converter 28, a DO port 29 for outputting a switching signal of the microcomputer 30 to the changeover switch 20, and a display device 3 for displaying a failure prediction signal.
1 and a DO port 32 for outputting a failure prediction signal. The electrode rod 18 is connected to the terminal 21 of the changeover switch 20, the terminal 22 is connected to the rectifier 36, the terminal 23 is connected to the current detector 24, and the terminal 21 is one of the terminals 22 and 23 depending on the output signal of the DO port 29. To be connected to.

Next, the concrete calculation contents of the second control device 27 relating to the present invention will be explained with reference to FIGS.

FIG. 3 shows a flowchart for explaining the processing contents of the water receiving tank 2 of the second control device 27. The second control device 27 uses the changeover switch 2 in block 102.
A signal for controlling 0 switching is calculated. As shown in FIG. 4, the switching signal is periodically output, and in synchronization with this, in block 103, the output signals of the voltage detector 25 and the current detector 24 are fetched from the A / D converter 28. In block 104, the conductivity (current / voltage) is calculated from the acquired voltage and current. In block 105, the conductivity is converted into the water level using the relationship of the conductivity between the electrode rod 18 and the electrode rod 16 with respect to the water level in the water receiving tank 2. Block 1
At 06, the water level change before the previous time is compared with the current water level to calculate the water level change. When the water level change is equal to or larger than a predetermined value, the block 107 determines that the water level is changing and executes the block 112. Otherwise, the constant water level valve 8 determines that the water level is in a stopped state, that is, the water level is constant. Execute block 108. This predetermined size is for separating the change in conductivity and the change in actual water level due to changes in water temperature and water quality of the water receiving tank.
In order to enable such a determination, the length of the electrode rod 18 may be set longer than the water level at which the ball tap 11 starts water supply. The block 108 calculates the maximum and minimum water levels by comparing the current water level data in the constant water level state and the previous constant water level data, and uses the maximum data in daily, weekly or monthly units as data for grasping the trend. , The minimum value is stored in the memory as the upper limit and the lower limit. A block 109 calculates the upper limit slope of the constant water level stored on a daily, weekly or monthly basis, and if there is an increasing tendency, determines that the constant water level valve 8 or the ball tap 11 has deteriorated and displays an alarm or output at block 111. To do. If the tendency is not increasing, block 110 calculates the lower limit slope of the constant water level stored on a daily, weekly, or monthly basis. Alarm display or output with. Block 10
If the change in water level is greater than or equal to a predetermined value in step 7, block 112 is determined to be changing and block 112 is executed.
Returns to block 102 and repeats a series of processing while the water level change is rising. Also, during the period when the water level change is falling,
In block 113, the time to reach the water level from the constant water level to the lower limit of the electrode rod 18 is measured. The measured time is stored in the memory on a daily, weekly or monthly basis as data for grasping the tendency. A block 114 calculates the inclination of the time stored in units of this day, week, or month, and when it has an increasing tendency, judges that the pumping capacity of the pump 5 has deteriorated and displays an alarm or outputs it in a block 111. If there is no increasing tendency, the process returns to block 102 and repeats a series of processes.

Next, with reference to FIG. 4, a brief description will be given of the data taken into the microcomputer 30 and the operational relationship of the conductivity measurement between the electrode rods 16 and 18. In the microcomputer 30, the changeover signal 201 is output to the changeover switch 20 at a predetermined cycle, and the terminal of the changeover switch 20 is applied so that the voltage of the DC power supply 44 is applied between the electrode rods 18 and 16 when the changeover signal is present. 21 and the terminal 23 are connected. In synchronization with this timing, the output signals of the voltage detector 25 and the current detector 24 are sent to the A / D converter 2
It takes in like 202 and 203 via 8, respectively. The ratio of these signals is calculated to obtain the conductivity 204. As described above, in the present invention, since the DC voltage is applied to the microcomputer 30 by applying the DC voltage for a very short time, the conductivity can be calculated at high speed and with high accuracy. The capacitor 33 shown in FIG. 1 is configured to be able to hold the output of the rectifier 36 at a predetermined value or more for a period equal to or longer than the time width of the switching signal 201 shown in FIG. This period can be shortened by using the DC power supply, and as a result, the capacitance of the capacitor 33 can be reduced.

As described above, according to the present invention, since it is possible to specify a water supply facility and predict a failure, an alarm output can be obtained at the stage of performance deterioration before the conventional failure detection operates. Can be made in advance.

[0017]

As described above, according to the present invention, it is possible to predict failure of a water supply system in an existing building at high speed and with high accuracy using an existing electrode rod without adding a new sensor. A control device for a water supply system of a building can be provided.

[Brief description of drawings]

FIG. 1 is a block diagram showing a control device for a building water supply facility according to an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram showing a control device of a water supply device for a building according to an embodiment of the present invention.

FIG. 3 is a flowchart for explaining processing contents for failure prediction by the control device shown in FIG.

FIG. 4 is a waveform diagram illustrating a calculation result of a switching signal, a captured voltage, a current, and a conductivity by the control device illustrated in FIG.

[Explanation of symbols]

 5 Pump 8 Constant Water Level Valve 11 Ball Tap 12 Sub-valve 13 Electrode Rod 20 Changeover Switch 24 Current Detector 25 Voltage Detector 26 First Control Device 27 Second Control Device 33 Capacitor 44 DC Power Supply

Claims (1)

[Claims] 1. A controller for a water supply system of a building, which monitors a water level in a water tank and controls a pump by a plurality of electrode rods having different lengths, wherein the electrode detects a low water level with respect to a constant water level position in the water tank. A means for detecting the conductivity between a common electrode bar paired with the bar at a predetermined cycle by using a direct current voltage, and the conduction and non-conduction of the electrode bar by using an alternating voltage, which is opposite to the predetermined cycle. A water supply apparatus for a building, comprising: a means for detecting the deterioration of the water supply equipment based on the output of the means for detecting the conductivity between the electrode rods and a means for outputting an alarm. Control device.