JP2511951Y2 - Control device for electric water heater - Google Patents

Description

[Detailed description of the device]

[0001]

[Industrial application] This invention is an electric water heater in which the main body side of a single specification electric water heater can be commonly used for both the late-night electric power type and the hourly charge system type. Regarding the control device.

[0002]

2. Description of the Related Art A conventional electric water heater is a so-called late-night electric power utilizing device, in which a heater power is supplied only in a predetermined midnight electric power supply time zone, for example, a time zone from 23:00 midnight to 7:00 the next morning. It is supposed to be done. However, in this case, since the other general loads are always energized, the power demand in the daytime can be positively suppressed, the power demand in the nighttime cannot be evoked, and the effect of leveling the power load can also be obtained. It was not always possible to achieve enough.

Therefore, a constant-current type electric water heater has been studied. In this case, the electric water heater is always energized just like other general loads, while the electricity charge system is
For example, the night time zone, which is equivalent to the conventional midnight power energization time zone, is set at a lower price than the other daytime hours,
Such a fee system is called a time zone fee system. However, on the contrary, the charge during the daytime period is set to be somewhat higher than the power charge for the conventional general load. In this case, the electric water heater will be referred to as a time zone charge system device hereinafter.

On the other hand, the conventional electric water heater uses late-night electric power to boil hot water in a tank to a preset boiling temperature and use the hot water during the daytime. Therefore, when the amount of hot water used increases or decreases depending on the day, the amount of hot water may occasionally become insufficient.However, even in that case, the heater power is not supplied unless the midnight power energization period arrives. It had the serious drawback that it could not be fired and could not add the required hot water at all. Under the hourly charge system, the electric water heater is constantly energized, so it has the advantage that it can be reheated at any time and that it can easily cope with an unexpected increase in the amount of hot water used.

[0005]

According to such a conventional technique, the electric water heater requires two types, that is, a type corresponding to the late-night power and a type corresponding to the charge system according to the time zone, depending on the usage form, and therefore, There is a problem that it is extremely complicated in terms of production management. The time-rate-based fee system type requires a complicated control device to enable additional boiling operation during the daytime hours, in addition to the boiling operation during the nighttime hours, while it supports midnight power. This is because the shape only needs to perform the boiling operation in the midnight power energization time zone, and there is no need to realize such a complicated control function.

Therefore, in view of the problems of the prior art, the object of the present invention is to provide a common cable drawn from the main body side of a single-spec electric water heater with a late-night power controller and a time zone-specific controller. By selecting either one of the above and connecting it, it is possible to arbitrarily realize the late night electric power type and the time zone fee system compatible type, and to reduce the complexity of manufacturing and production management. It is to provide a control device for an electric water heater that can be significantly reduced.

[0007]

The structure of the present invention for achieving the above object is to provide an output cable from a plurality of temperature sensors arranged on a peripheral wall of a tank, a control cable for a heater incorporated in the tank, and a heater power supply. A common cable consisting of the output cable from the voltage detection circuit that detects the presence or absence of the electric cable The gist of the present invention is to enable connection by selecting either one of the time-division controllers that operate as the time-division fee system equipment.

The time zone controller can also be used as the midnight power controller.

[0009]

According to the structure of the present invention, the common cable drawn from the main body side is composed of the output cable from the temperature sensor, the heater control cable, and the output cable from the voltage detection circuit. Through the input / output signals on these cables, it is possible to realize both control as a device that uses late-night power and control as a device for a time zone charge system. For the former, the average temperature in the tank is calculated from the output of the temperature sensor, and by controlling the heater energization by monitoring the average temperature, boiling operation in the midnight power energization time zone is possible, and for the latter, Similarly, the boiling operation in the night time zone and the additional boiling operation in the day time zone are possible. Therefore, if the electric water heater is connected to this common cable with a controller for late-night power, it will be compatible with late-night power, and if it is connected with a controller for different time zones, it will be compatible with a charge system for different time zones. it can.

If the controller for each time zone is also used as the controller for late-night power, the former can be commonly used for both purposes, so that the whole production management system can be further simplified. it can.

[0011]

Embodiments Embodiments will be described below with reference to the drawings.

The controller of the electric water heater comprises a common cable CA drawn from the main body side and a time zone controller 10 connected to the common cable CA (FIG. 1).

A heater H is installed in a tank TK of the electric water heater, and a water supply pipe TK1 is provided on the bottom surface of the tank TK.
And a hot water supply pipe TK2 is provided on the upper surface. The water W supplied through the water supply pipe TK1 is stored in the tank T
Filled in K, heated by heater H to become hot water,
Hot water is supplied to the place of use via the hot water supply pipe TK2.

A plurality of temperature sensors S1, S1 ... Are arranged vertically on the peripheral wall of the tank TK, and a heater H is provided.
Is connected to the heater power supply AC via a contact MCa of the electromagnetic contactor MC for opening and closing. A voltage detection circuit UV for detecting the presence / absence of the heater power supply AC is connected to the heater power supply AC.

The time zone controller 10 is a judgment control means 1
1 and the nighttime hot water temperature setting device 1 attached to the judgment control means 11
2, equipped with an additional boiling setting device 13, a clock 14,
Between the additional boiling setting device 13 and the judgment control means 11,
A changeover switch SW for changing the mode between “midnight power” and “by time zone” is provided. Also, the judgment control means 11
A mode selector switch SW1 for selecting the "automatic" mode is connected to.

Temperature sensors S1, S1 ..., Electromagnetic contactor M
C, the voltage detection circuit UV, and the judgment control means 11 are connected via the output cable CA1, the control cable CA2, and the output cable CA3, respectively, and the output cables CA1, CA3, and the control cable CA2 are collectively. It is assumed that the common cable CA is formed.

The time zone controller 10 includes a changeover switch S.
Switch the W to the "by time zone" side to add the additional boiling setting device 13
Is connected to the judgment control means 11, the electric water heater can be operated as a device for a time zone charge system, and at that time, the heater power supply AC is always energized. Further, when the changeover switch SW is switched to the "midnight power" side and the additional boiling setting device 13 is disconnected from the judgment control means 11, the electric water heater operates as a device using the midnight power,
At that time, the heater power supply AC is connected to the commercial power supply via a timer for late-night power, which is not shown, and is energized only in a predetermined late-night power energization time zone.

The operation of the judgment control means 11 when the changeover switch SW is on the "midnight power" side can be represented, for example, by the program flow chart of FIG.

When the voltage detection circuit UV detects that the heater power supply AC has been energized at the start time of the midnight power energization time zone, the program detects the voltage detection circuit UV.
To launch via. The program first checks whether or not the mode changeover switch SW1 is "automatic" (step (1) in FIG. 2, hereinafter simply referred to as (1)). The boiling temperature To1 set in the hot water temperature setting device 12 is read (2).

When the mode changeover switch SW1 is "automatic" (1), the boiling temperature To1 is calculated by the following procedure (3), for example. That is, the maximum value max (X1i) of the hot water usage amount data X1i (i = 1, 2, ...) In the past several days may be used, and To1 = max (X1i) + Tw + α. However, the usage amount X1i is represented by the average temperature in the tank TK, and can be obtained as X1i = Ta1-Ta2 + a.th.

Here, Ta1 and Ta2 are temperature sensors S1 and
Average temperature T in the tank TK obtained from each output of S1 ...
av is read once a day at any designated time, and the average temperature Tav of the day is Tav = Ta1 and the average temperature Tav of the previous day is Tav = Ta2, where a is the tank TK per unit time when the heater H is energized. Is a constant that indicates the average temperature rise within.
Further, th is the energization time of the heater H in the past 24 hours from the specified time, and can be obtained by measuring the closing time of the electromagnetic contactor MC, and the water temperature Tw is the temperature sensor S1 at the bottom of the tank TK. Can be measured by α is a constant indicating a margin.

The boiling temperature To1 calculated in this way is compared with the maximum allowable boiling temperature Tmax allowed in the tank TK. When To1 <Tmax, To1 = To1 To1 ≧ Tmax In the case of, To1 = Tmax is set and the upper limit is clipped. However, Tmax is generally set to about Tmax = 88 (° C.).

Thereafter, the program turns on the electromagnetic contactor MC and energizes the heater H (4), and the average temperature Tav is Tav ≧
After waiting for To1 (5), the heater H is shut off (6).

When the changeover switch SW is on the "by time zone" side, the judgment control means 11 is activated at the start times of the daytime time zone and the nighttime time zone, for example, and its operation is the program of FIG. Follow the flow chart.

When the program is started, it is checked whether it is a daytime time zone (step (1) in FIG. 3, hereinafter simply referred to as (1)), and when it is a nighttime time zone. The boiling operation in the night time zone is executed according to the program flowchart of FIG. 2 (2).

During the daytime (1), the program first reads the set value Va of the additional boiling setting device 13 (3). Here, the set value Va represents the amount of additional boiling water in the daytime period, for example, by the amount of hot water Tx equivalent hot water, and the set value Va does not specifically indicate the amount of hot water, but simply It can also be specified as "maximum".

Therefore, when the set value Va is "maximum" (4), the program executes the automatic additional boiling operation in the daytime zone (5). Here, the automatic additional boiling operation means, for example, energization control of the heater H so as to maintain the average temperature Tav in the tank TK at the maximum allowable boiling temperature Tmax. Is equal to the maximum allowable boiling temperature Tmax, and the tank T
An amount of hot water equal to the volume Vo of K can be constantly boiled and prepared in the tank TK.

When the set value Va is not "maximum" (4), the manual additional boiling of hot water corresponding to the set value Va is performed (6). That is, first, the required energization time t2 of the heater H is calculated by the following equation. t2 = Va (Tx -Tw) / A A = 860 x KW xy where KW is the electric power capacity of the heater H and y is the heating efficiency. Then, the energization control of the heater H may be continued until the energization time th of the heater H becomes th ≥t2 within the range of Tav≤Tmax.

The set value Va is set by attaching a selection switch (not shown) to the additional boiling setting device 13.
The switching setting of "valid only on the current day", "valid only on the next day", and "valid every day after the next day" may be possible. At this time, the program of FIG. 3 is made to start each time the selection switch is operated or each time the additional boiling setting device 13 is set, and the latest set value Va is set to the latest selection switch setting. It is good to read it together with the status. Further, both the automatic additional boiling operation (5) and the manual additional boiling operation (6) of FIG. 3 are assumed to be stopped by the elapse of the daytime time zone.

As described above, the controller 10 for each time zone is
By switching the changeover switch SW to the "by time zone" side, the electric water heater can be operated as a device for a time zone charge system, and by switching to the "midnight power" side, the electric water heater can be operated at the midnight power. It can be operated as a utilization device. Therefore, this one also serves as the controller for the late-night power.

[0031]

[Other Embodiments] On the other hand, a late-night power controller 10a dedicated to late-night power can be connected to a common cable CA including the tank TK, the electromagnetic contactor MC, and the voltage detection circuit UV, which is pulled out from the main body side (Fig. 4). Midnight power controller 10a
Differs from the time zone-specific controller 10 in FIG. 1 in that it does not include the additional boiling setting device 13 and the changeover switch SW, and its operation is basically as shown in the program flowchart in FIG.

In this case, the controller 1 for each time zone shown in FIG.
0, or in FIG. 1, a separate controller for the time zone dedicated to the time zone charge system without the changeover switch SW is separately prepared, and when the electric water heater is used as the late-night power utilization device, the common cable CA is used. When the controller 10a for late-night power is connected and is used as a device for a time zone charge system, the time zone controller may be connected. Both can select and connect to the common cable CA through the same interface.

If the "automatic" mode for night boiling is not provided, step (1) in FIG.
(3) may be deleted. At this time, the mode changeover switch SW1 of FIGS. 1 and 4 may be deleted and the timepiece 14 of FIG. 4 may be deleted. Also, even if there is an "automatic" mode for night boiling, the heater H used there
Similarly, the clock 14 in FIG. 4 can be eliminated by measuring the energization time th of the above with a counter that operates based on the frequency of the heater power supply AC, for example. Further, the night boiling may include a so-called peak shift function, and even in this case, if the peak shift time is measured by the timer, the clock 14 in the midnight power controller 10a is not always essential.

[0034]

As described above, according to the present invention, the midnight power control is performed on the common cable including the output cable from the temperature sensor, the control cable for the heater, and the output cable from the voltage detection circuit. If you connect the controller for midnight power by selecting and connecting either the water heater or the controller for different time zones, you can operate the electric water heater as a device that uses power at night, and If a separate controller is connected, it can be operated as a device for time-of-day charge system. Since it can be commonly used for both, there is an excellent effect that complexity in production and production control can be significantly reduced.

Further, the controller for the midnight power is simpler in its structure, so that the cost is lower than that for the controller for each time zone, and the usage method is simple and easy to use. There is also a practical effect that even when changing to a different fee system compatible type, it can be easily handled by simply replacing only the controller.

[Brief description of drawings]

FIG. 1 is a block diagram of the overall configuration

FIG. 2 Program flow chart (1)

[Figure 3] Program flow chart (2)

FIG. 4 is a block diagram showing the main part of another embodiment.

[Explanation of symbols]

 TK ... Tank H ... Heater AC ... Heater power supply S1 ... Temperature sensor UV ... Voltage detection circuit CA ... Common cable CA1, CA3 ... Output cable CA2 ... Control cable 10 ... Time zone specific controller 10a ... Midnight power controller

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-1-239344 (JP, A) JP-A-2-219949 (JP, A)

Claims (2)

(57) [Scope of utility model registration request] 1. A common cable comprising an output cable from a plurality of temperature sensors arranged on a peripheral wall of a tank, a control cable of a heater incorporated in the tank, and an output cable from a voltage detection circuit for detecting the presence or absence of a heater power supply. From the main body side, with respect to the common cable, a controller for late-night power that operates the electric water heater as a device that uses late-night power,
A control device for an electric water heater, which can be connected by selecting either one of a time-division controller that operates the electric water heater as a time-division fee system device. 2. The controller for an electric water heater according to claim 1, wherein the controller for each time zone is also used as the controller for the midnight power.