JPH08201146A - Float type water level transmitter with malfunction detecting function - Google Patents

Abstract

PURPOSE: To provide a float type water level transmitter having a malfunction detecting function which can judge by itself whether the detected water level data is accurately or not by using the one float type water level transmitter. CONSTITUTION: The float type water level transmitter with a malfunction detecting function comprises a water level detector which has an unbalance float 1 and a wire 3 suspended with a weight 4 from its one end, wound at the intermediate on a pulley 2 rotating integrally with a rotary shaft, and mounted at the other end at the float 1 to float the float 1 at the water level in balance, a water level signal converter (potentiometer) 5 rotated by the rotary shaft to output a water level signal responsive to the changer of a water level, and a malfunction detector for detecting the malfunction of the detector depending upon whether there is an electric continuity among three electrodes provided at the float 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention detects the water level in a regulating pond or a water tank of a hydroelectric power plant and sends the detection result to a generator control panel installed in the building of the hydroelectric power plant. The improvement of the float type water level transmitter that is displayed on the water level gauge of the generator control panel, especially when an abnormality occurs in the float type water level transmitter, the abnormality is detected and an alarm is issued as necessary. The present invention relates to a float type water level transmitter having an abnormality detecting function.

[0002]

2. Description of the Related Art In a hydroelectric power plant, running water is introduced from a dam, a regulating pond or a water tank into a water turbine through a hydraulic pipe to rotate the water turbine, and a generator directly connected to the water turbine generates electricity. Flow rate of water to be introduced into the turbine (approximately the output power of the generator)
Is controlled according to the amount of flowing water flowing into the dam, the regulating pond or the water tank, etc., and generally, the water level adjusting control is performed to keep the water level of the dam, the regulating pond, the water tank or the like substantially constant.

For this reason, in a hydroelectric power plant, it is necessary to provide a water level transmitter for detecting the water level in a regulating pond or the like. Normally, a float type water level transmitter is installed in the hydroelectric power plant. It is an extremely important device for the control of.

FIG. 4 is a schematic diagram showing the principle of a conventional float type water level transmitter.

In FIG. 4, reference numeral 1 denotes a float, which floats above the water surface of a dam, a regulating pond or a water tank, and moves up and down in response to rising and falling of the water surface to detect the water surface water level. Acts as a detector. The outer shape is obtained by joining two hollow right circular cones having the same shape to each other at the peripheral edges of the respective bottom surfaces.

Reference numeral 2 is a pulley, which is supported by a bearing (not shown) at the center thereof and which is integral with the pulley 2.
Although not shown, a groove for winding a wire, which will be described later, is provided. Reference numeral 3 is a wire, a weight 4 is suspended at one end thereof, an intermediate portion is wound around the groove of the pulley 2 for half a circumference, and the other end is attached to the top end of the float 1.

Therefore, in the float 1 floating on the water surface,
The upward force generated by the weight 4 always acts on the wire 3, and the wire 3 does not loosen. Therefore, when the float 1 moves up or down according to the rise or fall of the water surface level, Due to the movement of the wire 3, the pulley 2 rotates counterclockwise together with the rotating shaft 2a when the water level rises.

Reference numeral 5 denotes a potentiometer, which has terminals at both ends thereof and which is formed in a circular shape with the rotating shaft 2a as a center, and a resistor 5a located at the center of the resistor 5a and having The pulley 2 comprises a slider 5b made of a conductor which is mounted coaxially with the rotating shaft 2a extended and which is rotated by the rotation of the rotating shaft 2a and slides on the resistor 5a. The terminal 5c is also provided at the base end of the child 5b.

The potentiometer 5 having the above-described structure is applied with an appropriate DC voltage through the lead wires 6 and 6 connected to both terminals of the resistor 5a, so that the float 1 which responds to the rise and fall of the water surface level can be The rotation of the rotary shaft 2a accompanying the rotation of the pulley 2 due to the downward movement causes the slider 5b to move to the resistor 5a.
The upper surface is rotated while slidingly contacting it to convert the mechanical motion into an electric signal, and a water level voltage signal corresponding to the water surface water level is obtained from a terminal 5a provided at the base end thereof.

The water level voltage signal thus obtained is
It is transmitted to the generator control panel installed in the building of the hydroelectric power plant via the lead wire 6a connected to the terminal 5a, and the water level is displayed on the water level gauge of the generator control panel.

The potentiometer 5 in this case is
Although it acts as a water level signal converter that converts mechanical motion into an electric signal, a Celsine oscillator may be used as the water level signal converter in addition to the potentiometer.

[0012]

As described above, the water level signal converter (potentiometer or celsin transmitter) of the float type water level transmitter has a float functioning mechanically from the function of detecting the water level. 1 or a pulley 2 etc. is required, but due to driftwood floating on the water surface, fallen leaves in the autumn, or freezing of the water surface in the winter, the float 1 may be inoperable despite the rise and fall of the water surface, Alternatively, the rotation of the pulley 2 may be hindered by dust or the like. And the float type water level transmitter
For the above reason, there is a problem in that even if a malfunction occurs in which the water surface level cannot be accurately transmitted, it cannot be detected.

Therefore, conventionally, as shown in FIG. 4, two float type water level transmitters including a float, a wire, a pulley and a potentiometer are provided and the water level data transmitted from each water level transmitter is monitored. Then
If the two data did not match, it was determined that the water level transmitter was defective.

However, providing two float type water level transmitters and a monitoring device for constantly monitoring two data is problematic in terms of cost, and moreover, a lot of manpower is required for maintenance and inspection of those devices. It took time and it was a problem.

The present invention has been made in view of the above circumstances, and an object thereof is to use one float type water level transmitter and to judge by itself whether or not the detected water level data is accurate. Another object of the present invention is to provide a float type water level transmitter having an abnormality detecting function.

[0016]

In order to achieve the above-mentioned object, the present invention is a float that is unbalanced by itself and floats above the water surface, and a weight is hung at one end,
Water level detection with a wire whose middle part is wound around a pulley that has a rotating shaft and rotates integrally with this rotating shaft, and whose other end is attached to the float to keep the float balanced and float on the water surface. And a rotary shaft that rotates together with the rotation of the pulley due to the up / down movement of the float in response to the rise / fall of the water surface,
A water level signal converter that outputs a water level signal in response to changes in the water level of the water surface, a first electrode that is attached to the float and is always submerged under the water surface, and is attached to the float, and this float maintains balance. The second electrode is attached to the float and the second electrode that comes into contact with the water surface when it floats above the water surface and is out of balance and floats above the water surface. Is connected to the third electrode, which is above the water surface when floating above, and is submerged below the water surface when unbalanced and above the water surface, and the first, second and third electrodes, An abnormality detection circuit device for detecting an abnormality of the water level detector based on the presence or absence of electrical conduction between the electrodes and the second and third electrodes;
It is characterized by consisting of.

[0017]

[Function] As a float for detecting the water level, when the water level detector is abnormal, the balance is lost and floats on the water surface, but when the water level detector is normal, the float floats on the water surface while maintaining the balance. Using this, three electrodes are attached to this float for detecting whether or not the float maintains balance, and the balance state of the float is detected by the presence or absence of electrical conduction between these three electrodes. Since the abnormality detection circuit device is provided and the balance state of the float is detected by this abnormality detection circuit device, it is possible to judge whether or not the detected water level data is accurate by using one float type water level transmitter. Becomes

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 1 is a schematic view showing an embodiment of the present invention, FIG. 2 is a developed connection diagram of an abnormality detection circuit device provided in a generator control panel (not shown) for detecting an abnormality of the present invention device, and FIG. It is explanatory drawing for demonstrating the external shape of the float of invention, an abnormal condition, and operation | movement of this invention apparatus. Note that, in FIG. 1, the same portions as those in FIG. 4 are denoted by the same reference numerals as those in FIG. 4, and thus detailed description thereof is omitted.

In FIG. 1, 1 is a float, 2 is a pulley, 2a is a rotating shaft of the pulley 2, 3 is a wire, and 4 is a weight. Reference numeral 5 denotes a potentiometer which operates as a water level signal converter, and has a resistor 5a having terminals at both ends thereof.
And a slider 5b having a terminal 5c at its base end, and 6,6,6a are lead wires respectively connected to the above-mentioned terminals. A Celsin oscillator may be used as the water level signal converter.

1 differs from FIG. 4 only in the float 1 which operates as a water level detector for detecting the water surface level. Since the float 1 differs from the conventional float in the following two points, the float 1 will be described below. The details will be described.

(1) In order to detect an abnormality of the float type water level transmitter, the float 1 is independently floating on the water surface regardless of the shape of its outer shape.
As shown in Figure 1, one side is made so that it is submerged in water and the balance is lost. Then, in the use state, the wire 3 is displaced from the top end and attached so as to maintain the balance and float on the water surface as shown in FIG.

As a method of breaking the balance of the float 1, as shown in FIG. 4 above, two hollow right circular cones having the same outer shape are joined to each other at the peripheral edges of their bottom surfaces. As shown in FIG. 1, a weight 1a having an appropriate weight is attached to one side of the inside so that the position of the center of gravity is biased to one side.

Alternatively, as shown in FIG.
The left and right sides may be manufactured asymmetrically to make one side heavier and the center of gravity may be biased to one side.

When using the float 1, as shown in FIG.
As shown in, the mounting position of the wire 3 is appropriately selected so as to float on the water surface while maintaining the balance.

(2) Three electrodes A, B and C satisfying the following conditions are further attached to the float 1 in which the position of the center of gravity is biased to one side.

(A) The first electrode [A] (see FIGS. 1 and 3) which is always submerged below the water surface regardless of the balance state of the float 1 floating above the water surface. (B) The second electrode [B] (FIG. 1, FIG. 3) which is always in contact with the water surface when the float 1 floating on the water surface maintains the balance state, and which appears on the water surface when the balance is lost. reference). (C) The third electrode [C] (FIG. 1, FIG. 3) that is floated above the water surface is always on the water surface when the balance state is maintained, and is submerged below the water surface when the balance is lost. reference).

Next, referring to FIG. 2, an abnormality of the float type water level transmitter using the three electrodes of the above-mentioned first electrode A, second electrode B and third electrode C is detected. An abnormality detection circuit device for doing so will be described.

FIG. 2 is a developed connection diagram of the abnormality detection circuit device 8 described above. In FIG. 2, P and N are control power supply buses and A
Is a first electrode, B is a second electrode, C is a third electrode, X,
Each Y is an auxiliary relay.

Reference numeral T denotes a time delay relay, which operates after a predetermined time elapses when an operation command signal is input. This time delay relay T, when the wave is generated on the water surface by the wind, even if the float 1 maintains a balanced state,
The above-mentioned three electrodes may be misjudged to be out of balance and may malfunction during abnormality detection. Therefore, these three electrodes are provided to prevent malfunction.

The first, second and third electrodes, A,
B and C are connected as shown in FIG. 2, drawn out by the lead wire 9 and guided to the abnormality detection circuit device 8. Further, the auxiliary relays, X, Y, and the time delay relay T, and the contacts of these relays, X, Y, T, are connected to the control power bus P,
Connected between N as shown.

By the way, these first, second and third
From the above conditions for the three electrodes A, B and C of
When float 1 is in balance,
The electrode A and the second electrode B are in a conductive state via “water”, and the first electrode A and the third electrode C are in a non-conductive state (see FIG. 1). ).

When the float 1 is out of balance, the first electrode A and the second electrode B are not electrically connected to each other, and the first electrode A and the third electrode C are not connected to each other. In between
It becomes conductive through “water” (see FIG. 3).

Here, for convenience of explanation, and in order to facilitate understanding of the abnormality detection circuit device, the float 1 is regarded as an auxiliary relay F and "water" is regarded as a movable contactor of the auxiliary relay. When the balance state is maintained, the auxiliary relay F is considered to be inoperative, and when the balance is lost, the auxiliary relay F is considered to be operational.
Between the electrodes B of, the normally closed contact (b contact) of the auxiliary relay F
(Hereinafter referred to as Fb), the first electrode A and the third electrode
Between the electrodes C of, the normally open contact (a contact) of the auxiliary relay F
(Hereinafter referred to as Fa) can be regarded as equivalent to.

For the above reason, in the expanded connection diagram of the abnormality detection circuit device shown in FIG. 2, the three electrode portions of the first, second and third A, B and C are used as the movable contacts of the auxiliary relay. The symbols Fa and F
b is attached.

The structure of the present invention has been described above. Next, the operation of the device of the present invention will be described with reference to FIGS. 1, 2 and 3.

There is no abnormality on the water surface, the float 1 keeps a balanced state and floats on the water surface, and the pulley 2, its rotating shaft 2a and the slider 5b of the potentiometer 5 which rotates with this rotating shaft 2a are normal. If so, the float 1 moves upward and downward while maintaining a balanced state in response to the rise and fall of the water surface level.

The upward and downward movements of the float 1 are transmitted to the pulley 2 via the wire 3, and together with the pulley 2, its rotation shaft 2a and the slider 5b of the potentiometer 5.
Rotate counterclockwise / clockwise to lead wires 6, 6a
A water level voltage signal corresponding to the water surface level is transmitted via.

As described above, when the float type water level transmitter is operating normally without any abnormality, the auxiliary relay F (float 1) is in the inoperative state, and therefore the normally closed contact Fb thereof is provided.
The circuit (between electrodes A and B) is closed, and the normally open contact Fa (electrodes A and C)
(Between) is open circuit.

Therefore, since the open / closed states of the contacts Fb, Fa in the expanded connection diagram of the abnormality detection circuit device shown in FIG. 2 are as shown in the drawing, the auxiliary relay X operates and the normally closed contact Xb opens. Further, the auxiliary relay Y does not operate and its normally open contact Ya is also open.

Therefore, since the time delay relay T does not operate and its normally open time limit contact Ta is not closed, no alarm command signal is issued.

On the other hand, if the pulley 2 cannot rotate due to driftwood floating on the water surface, fallen leaves in the autumn, freezing of the water surface in the winter, or due to dust or the like, the float 1 moves even if the water surface level drops. It becomes impossible to follow the drop in water level. Therefore, the float 1 floats and is suspended by the wire 3, and the electrode B that was in contact with the water surface is separated from the water surface, so that the electrodes B and A are not electrically connected to each other. That is, auxiliary relay F
(Float 1) is activated and its normally closed contact Fb
The circuit (between electrodes A and B) is opened.

That is, in the expanded connection diagram, the normally closed contact Fb is opened, the auxiliary relay X is deactivated, and the normally closed contact Xb is closed, so that the time delay relay T operates.
Therefore, the normally-open time limit contact Ta is closed after a predetermined time to issue an alarm command signal to an alarm device (not shown) to give an alarm.

On the contrary, when the water level rises and the pulley 2 is not rotatable due to dust or the like, the float 1 rises as the water level rises.
Slack occurs in the. Therefore, the float 1 that is manufactured by itself being out of balance tilts as shown in FIG. 3, the electrode B in contact with the water surface separates from the water surface, and the electrode C on the water surface sinks below the water surface. become. Therefore, the electrode B and the electrode A are in a non-conductive state, and the electrode A and the electrode C are in a conductive state. That is, the auxiliary relay F (float 1) is in an operating state, and its normally closed contact Fb (electrode A
・ B) is opened, and normally open contact Fa (between electrodes A and C) is closed.

That is, in the expanded connection diagram, the open / closed states of the normally closed contact Fb and the normally open contact Fa are opposite to those shown in the drawing, so that the auxiliary relay X is inoperative and the normally closed contact Xb is closed. Further, the auxiliary relay Y operates to close the normally open contact Ya as well.

Therefore, the time delay relay T operates and the normally open time limit contact Ta closes after a predetermined time, so an alarm command signal is issued to an alarm device (not shown) to give an alarm. In this way, according to the present invention, it is possible to detect an abnormality in the float type water level transmitter regardless of whether the water level rises or falls.

[0046]

The present invention has been described in detail above. However, according to the present invention, the float of the water level detector is itself unbalanced, and when an abnormality occurs in the water level detector or the water surface, it is unbalanced. Therefore, the imbalance of the float is detected by the three electrodes provided on the float. Therefore, if one float type water level transmitter is used, whether or not the detected water level data is accurate. The advantage of being able to obtain a float type water level transmitter with an abnormality detection function that can detect not only the abnormality of the water level detector but also the abnormal operation of the water level detector caused by the abnormality of the water surface is there.

[Brief description of drawings]

FIG. 1 is a schematic view showing an embodiment of the present invention.

FIG. 2 is a developed connection diagram of an abnormality detection circuit device for detecting an abnormality of the device of the present invention.

FIG. 3 is an explanatory diagram for explaining the outer shape of the float of the present invention, an abnormal state, and the operation of the device of the present invention.

FIG. 4 is a schematic view showing the principle of a conventional float type water level transmitter.

[Explanation of symbols]

 1 Float 2 Pulley 2a Rotary shaft of pulley 3 Wire 4 Weight 5 Potentiometer 5a Resistor 5b Slider 6 Lead wire 6a Lead wire 8 Abnormality detection circuit device 9 Lead wire

Claims (1)

[Claims] 1. A float that floats on the surface of the water by itself losing its balance, and a weight is suspended at one end,
Water level detection with a wire whose middle part is wound around a pulley that has a rotating shaft and rotates integrally with this rotating shaft, and whose other end is attached to the float to keep the float balanced and float on the water surface. And a rotary shaft that rotates together with the rotation of the pulley due to the up / down movement of the float in response to the rise / fall of the water surface,
A water level signal converter that outputs a water level signal in response to changes in the water level of the water surface, a first electrode that is attached to the float and is always submerged under the water surface, and is attached to the float, and this float maintains balance. The second electrode is attached to the float and the second electrode that comes into contact with the water surface when it floats above the water surface and is out of balance and floats above the water surface. Is connected to the third electrode, which is above the water surface when floating above, and is submerged below the water surface when unbalanced and above the water surface, and the first, second and third electrodes, An abnormality detection circuit device for detecting an abnormality of the water level detector based on the presence or absence of electrical conduction between the electrodes and the second and third electrodes;
A float type water level transmitter having an abnormality detecting function.