JPS6199055A - Control circuit for electric water heater - Google Patents

Abstract

PURPOSE:To improve the economical property of the water heater much more by a method wherein the time of conduction of a daytime electric heater is permitted to set so as to conform with the actual using condition of an user. CONSTITUTION:When midnight electric power is stopped, a midnight electric power detecting circuit 10 outputs midnight electric power stopping signal. A midnight electric heater control circuit 19 opens a relay 20 to stop the conduction of a night electric heater 4 and, at the same time, a timer circuit 16 starts the operation of a timer. A daytime electric heater control circuit 17 controls the conduction of a daytime electric heater 5 as far as the midnight electric power stopping signal from the detecting circuit 10 and the timer operating signal from the timer circuit 16 are existing. When the timer circuit 16 outputs the timer stopping signal, a control circuit 17 holds the relay 18 in an opened condition and stops the conduction of the daytime electric heater 5. The conduction time of the daytime electric heater 4 may be elongated by increasing the operating volume of a time setting unit 21 while it may be shortened by decreasing the same.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention includes a nighttime electric heater that heats water in a hot water storage tank using late-night electricity, and a daytime electric heater that heats water using daytime electricity. 2 Load 2 A daytime electric heater that uses daytime electricity is installed in the conventional electric water heater that uses late-night electricity for the purpose of downsizing the hot water storage tank and saving energy. 2
In an electric water heater with two load power sources, the daytime electric heater is used to replenish the small amount of hot water used for cooking in the morning. The most effective time to apply electricity is in the morning, from the time the electricity is cut off at midnight until the evening. After that, you can save energy by turning on the power late at night. For example, if a large amount of hot water in the hot water storage tank is used for taking a bath at 8 p.m., water is supplied to the hot water storage tank and the electric heater is energized during the day until the midnight electricity starts. However, if the power is turned on after 8 p.m., it will not be possible to use it that day, and there is no point in turning on the power. Moreover, daytime electricity is more expensive than late-night electricity, making it less economical, and heating up earlier, resulting in greater heat dissipation loss, which goes against energy conservation.

This has the following problem.

A possible solution to this problem is to provide the daytime electric heater with a timer circuit so that the daytime electric heater can only be energized within a certain period of time. However, since this timer time is a fixed time, it is very inconvenient for users to use. For example, if a timer circuit is used to set the 11 hours from 7 a.m. to 6 p.m., when power is cut off at midnight, as the daytime electric heater's energization time, the daytime electric heater will not be energized when hot water is supplied after 6 p.m. Therefore, the problem of wasted daytime power supply does not occur. However, if a large amount of hot water is used for bathing or the like at 4 p.m., the electric heater will remain energized during the day until 6 p.m., which poses a problem that is not economical. Since bathing times vary from user to user, even if you simply shorten the energization time of the electric heater during the day, there is a problem in that for users who take a bath after 6 pm, the ability of the electric heater during the day will decrease. It is.

Purpose of the Invention In view of the above-mentioned conventional problems, the present invention has been made to reduce daytime electric power by allowing a timer circuit to energize a daytime electric heater that heats water in a hot water storage tank using daytime electric power. This eliminates wasteful energization and improves economic efficiency, and also solves the problem that the boiling time is too early, which goes against energy conservation. In addition, it is equipped with an operation panel that adjusts the timer time of the timer circuit and changes the energization time of the electric heater during the day, making it possible to set the energization time according to the user's actual usage, further increasing economic efficiency. It is.

Structure of the Invention The basic structure of the present invention to achieve the above object is to include a nighttime electric heater that heats the water in the hot water storage tank using late-night electricity, and a nighttime electric heater that heats the water in the hot water storage tank using daytime electricity. 1, a timer circuit that enables the daytime electric heater to be energized only for a certain period of time; and 1, a time setting section that adjusts the timer time, the timer time of the timer circuit being freely variable. It is configured to do this.

DESCRIPTION OF THE EMBODIMENTS FIG. 1 is a block diagram of a two-load, two-source electric water heater. It is equipped with a nighttime electric heater 4 that heats up by electricity during the daytime, a daytime electric heater 5 that heats up by daytime electricity, and a boiling sensor 6 that detects the temperature of hot water in a hot water storage tank, and a control circuit 7 that controls the energization of the heaters.

FIG. 2 shows a block diagram of the circuit of this embodiment.

8 is a late-night power supply that is turned on for a certain period of time in the middle of the night, 9 is an earth leakage breaker, and 10 is a late-night power detection circuit that outputs a signal to turn on and stop the late-night power. 4 is an electric heater at night,
Electricity is supplied by the operation of the relay 20. 11 is the relay 2
0 contact point. 12 is constantly energized by daytime power supply. 13 is an earth leakage breaker, and 5 is a daytime electric heater, which is energized by the operation of a relay 18. 14 is a contact point of the relay 18. 15 is a power supply circuit that generates a DC voltage used for control signals. 16 is a timer circuit, which starts timer operation in response to a signal from the late-night power detection circuit to stop the late-night power supply; 17 is a daytime electric heater control circuit that opens and closes the relay 18 only while the timer circuit 16 is operating; I do. While the timer operation is stopped and while the late-night power detection circuit 1° is detecting the late-night power, the relay 18 remains open. Reference numeral 19 denotes a nighttime electric heater control circuit, which opens and closes the relay 20 while the nighttime power detection circuit 10 detects the latenight power. The relay 20 remains open during the midnight power outage. Reference numeral 21 denotes a time setting section which is represented by, for example, a volume, and can be arbitrarily changed by the user. This makes it possible to freely set the energization time of the electric heater during the daytime.

Fig. 3 Kfil] shows the operating state. fal is a conventional example, and there is a possibility that the daytime electric heater is constantly energized while the electric power is stopped in the middle of the night, depending on the boiling state of the hot water storage tank. f
bl is for this example. When the late-night power is stopped at 7 am, the late-night power detection circuit 10 outputs a late-night power stop signal. This signal causes the night electric heater control circuit 19 to
The relay 20 is opened to stop energizing the electric heater 4 at night. At the same time, the timer circuit 16 starts timer operation and outputs a signal indicating that the timer is operating to the daytime electric heater control circuit 17. In this example, the timer operation time is T1, which is Vi10 hours. Daytime electric heat control circuit 17
The relay 18 is activated due to the boiling state in the hot water storage tank while there is a signal to stop power at night from the late night power detection circuit 10 and a timer operation signal from the timer circuit 16.
is opened and closed to control energization of the electric heater 5 during the daytime.

After 10 hours, the afternoon S hour timer circuit 16 times up and outputs a signal to stop the timer. In response to this signal, the daytime electric heater control circuit 17 holds the relay 18 in an open state and stops energizing the daytime electric heater 5.

This saves wasted daytime power in the hatched area shown in FIG. 3 (bl).

Late-night power detection circuit 1 is activated by turning on late-night power at 11 p.m.
0 outputs a signal for late-night power supply. Late-night electric heater control circuit 1
9 opens and closes the relay 2o to control energization of the electric heater 4 at night. This state continues until 17:00 on the next day, after which the same operation as described above is repeated.

The energization time of the electric heater 4 during the daytime can be made longer by increasing the operation volume of the time setting section 21, and can be made shorter by decreasing it.

FIG. 3(0) is an example in which the energization time is shortened.

Effects of the Invention As described above, according to the present invention, by enabling the electric heater to be energized during the daytime only for a certain period of time, it is possible to improve economic efficiency by eliminating unnecessary use of daytime power, and to avoid unnecessary boiling. It can also prevent the fuel from heating up too quickly and improve energy savings. Furthermore, by setting the energization time of the electric heater during the day according to the user's actual deafness, economical efficiency can be further improved.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of a two-load, two-power electric water heater; Fig. 2 is a block diagram of a circuit according to an embodiment of the present invention; Fig. 3 -
FIG. 3 is a sequence diagram of a C-turning operation. 1...Hot water storage tank, 4...Night electric heater, 5...
・Daytime electric heater, 16...Timer circuit, 21...
...Time setting section. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 3

Claims (1)

[Claims] A nighttime electric heater that heats the water in the hot water storage tank using late-night electricity, a daytime electric heater that uses daytime electricity to heat the water in the hot water storage tank, and energizing the daytime electric heater only for a certain period of time. What is claimed is: 1. A control circuit for an electric water heater, comprising: a timer circuit that enables the timer circuit; and a time setting section that adjusts the timer time; the control circuit is configured to arbitrarily set the timer time of the timer circuit.