JPH026980B2 - - Google Patents

Info

Publication number
JPH026980B2
JPH026980B2 JP14080883A JP14080883A JPH026980B2 JP H026980 B2 JPH026980 B2 JP H026980B2 JP 14080883 A JP14080883 A JP 14080883A JP 14080883 A JP14080883 A JP 14080883A JP H026980 B2 JPH026980 B2 JP H026980B2
Authority
JP
Japan
Prior art keywords
hot water
amount
temperature
heat
data
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
JP14080883A
Other languages
Japanese (ja)
Other versions
JPS6030940A (en
Inventor
Hideji Kubota
Kazuo Hara
Yoshikazu Ito
Hiroshi Yamaguchi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsubishi Electric Corp
Original Assignee
Mitsubishi Electric Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Mitsubishi Electric Corp filed Critical Mitsubishi Electric Corp
Priority to JP58140808A priority Critical patent/JPS6030940A/en
Publication of JPS6030940A publication Critical patent/JPS6030940A/en
Publication of JPH026980B2 publication Critical patent/JPH026980B2/ja
Granted legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G05CONTROLLING; REGULATING
    • G05DSYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
    • G05D23/00Control of temperature
    • G05D23/19Control of temperature characterised by the use of electric means
    • G05D23/1919Control of temperature characterised by the use of electric means characterised by the type of controller
    • G05D23/1923Control of temperature characterised by the use of electric means characterised by the type of controller using thermal energy, the cost of which varies in function of time

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Automation & Control Theory (AREA)
  • Heat-Pump Type And Storage Water Heaters (AREA)

Description

【発明の詳細な説明】 この発明は、深夜電力を利用する貯湯式電気温
水器の制御装置に関し、使用者側の湯量使用の実
績に基づいて貯湯タンク内に貯えておくべき所要
熱量を算出するようにして、従来、固定であつた
貯湯式電気温水器の能力を使用者側の実体に合わ
せて使用できるようにすることを目的としてい
る。
[Detailed Description of the Invention] The present invention relates to a control device for a hot water storage type electric water heater that uses late-night electricity, and calculates the required amount of heat to be stored in a hot water storage tank based on the user's actual hot water usage. In this way, the purpose of the present invention is to enable the user to use the capacity of a hot water storage type electric water heater, which has conventionally been fixed, in accordance with the actual situation of the user.

第1図は一般的な貯湯式電気温水器の構成図
で、第2図は従来の貯湯式電気温水器の主要電気
回路図を示す。
FIG. 1 is a block diagram of a general hot water storage type electric water heater, and FIG. 2 is a main electrical circuit diagram of a conventional hot water storage type electric water heater.

これらの図において、1は貯湯タンク、2は給
水管、3は給湯管、4は出湯栓、5は発熱体、6
は自動温度調節器、7は電源、8は深夜電力用の
タイムスイツチで、その通電時間帯は一般には23
時から翌朝の7時までの8時間である。
In these figures, 1 is a hot water storage tank, 2 is a water supply pipe, 3 is a hot water supply pipe, 4 is a hot water tap, 5 is a heating element, 6
is an automatic temperature controller, 7 is a power supply, and 8 is a time switch for late-night power, which is generally turned on around 23:00.
8 hours from 7:00 to 7:00 the next morning.

次に上記構成よりなる従来例の動作を説明す
る。深夜電力の通電開始時刻になると、タイムス
イツチ8の接点が閉成して、発熱体5への通電が
開始される。そして貯湯タンク1内の湯温が85℃
になると、自動温度調節器6の接点が開成して発
熱体5への通電が停止される。その後は自動温度
調節器6の開閉により湯温が85℃に保たれ、この
ようにして毎朝貯湯量全部が85℃に沸き上つてい
る。
Next, the operation of the conventional example having the above configuration will be explained. When the time to start supplying late-night power comes, the contact of the time switch 8 is closed and the supply of electricity to the heating element 5 is started. And the water temperature in hot water storage tank 1 is 85℃.
When this happens, the contacts of the automatic temperature regulator 6 are opened and the power supply to the heating element 5 is stopped. Thereafter, the water temperature is maintained at 85°C by opening and closing the automatic temperature controller 6, and in this way, the entire stored hot water is heated to 85°C every morning.

このように、貯湯式電気温水器では貯湯効率を
高めるため、沸き上り温度をできる限り高温に設
定し、その設定温度に達すると加熱を停止する構
造となつている。しかし、使用者は高温湯のまま
使用するのではなく、水と混合して40〜45℃前後
の混合湯として使用する。その得られる混合湯量
を求める式は次の通りである。
In this way, in order to increase the efficiency of hot water storage, electric hot water heaters are designed to set the boiling temperature as high as possible, and stop heating when the set temperature is reached. However, users do not use high-temperature hot water as it is, but mix it with water and use it as a mixed hot water at around 40 to 45 degrees Celsius. The formula for determining the amount of mixed hot water obtained is as follows.

今、貯湯タンク容量をVt()、貯湯タンク1
内の沸き上り温度をTo(℃)、得ようとする混合
湯の温度をTm(℃)、混ぜ合わせる水の温度(給
水温度)をTi(℃)とすると、混合湯量Vm()
は、 Vm=Vt×To−Ti/Tm−Ti() で表わせる。
Now, the hot water storage tank capacity is Vt (), hot water storage tank 1
If the boiling temperature in the water is To (℃), the temperature of the mixed water to be obtained is Tm (℃), and the temperature of the water to be mixed (water supply temperature) is Ti (℃), the mixed hot water volume Vm ()
can be expressed as Vm=Vt×To−Ti/Tm−Ti().

この算式において、給水温度Tiは季節によつ
て大きく変動する。東京では冬は5℃位から、夏
には27℃位にまで達する。このため、適温の混合
湯として得られる湯量は、冬期には少なく、夏期
には多いということになる。すなわち、沸き上り
温度Toを85℃として、給水温度Tiが5℃の時に
対して、27℃の時に得られる混合湯量Vmは1.6倍
にも達する。
In this formula, the water supply temperature Ti varies greatly depending on the season. In Tokyo, temperatures range from around 5°C in winter to around 27°C in summer. Therefore, the amount of hot water that can be obtained as mixed hot water at an appropriate temperature is small in the winter and large in the summer. That is, when the boiling temperature To is 85°C, the amount of mixed hot water Vm obtained when the water supply temperature Ti is 5°C is 1.6 times that obtained when the water supply temperature Ti is 27°C.

一方、湯の使用量は年間ほぼ一定か、むしろ夏
期の方が低温湯で使用するため、実質的な使用量
が低下するのが一般的であり、冬期よりも夏期の
残湯量が多くなる。さらに、使用者によつては家
族数の減少などによつて定格の1/2とか、2/3とか
しか使用せず、毎日多くの湯を残す使い方をす
る。
On the other hand, the amount of hot water used is almost constant throughout the year, or rather, the actual amount used is generally lower in the summer because hot water is used at a lower temperature, and the amount of hot water remaining in the summer is larger than in the winter. Furthermore, some users use only 1/2 or 2/3 of the rated amount due to a decrease in the number of family members, leaving a large amount of hot water available each day.

このように、給水温度Tiが高かつたり残湯が
あると、沸き上りも早く、高温湯を長時間使用に
供さないで放置することになる。
In this way, if the water supply temperature Ti is high and there is residual hot water, the hot water will boil quickly and the hot water will be left unused for a long time.

このように、不必要に高い温度の湯を長時間使
用に供さないで放置することは、貯湯タンク1か
らの自然放熱および配管内の滞留した温水の放熱
等による熱ロスが大きくなるという欠点があつ
た。
In this way, leaving unnecessarily high-temperature hot water unused for a long time has the disadvantage of increasing heat loss due to natural heat radiation from the hot water storage tank 1 and heat radiation from hot water stagnant in the pipes. It was hot.

この発明は、これらの欠点を解消しようとする
もので、記憶装置に湯量の使用実績、例えば過去
10日間の使用湯量を熱量のデータとして記憶し、
このデータは毎日、その日の使用湯量により更新
するように、すなわち学習機能を有するように
し、このデータに基づいて所要の混合湯量が常に
得られるよう、発熱体への所要通電時間を算出
し、発熱体への電力の供給が深夜電力の供給開始
から供給終了までの全時間に亘つて平準化して行
われるように制御することにより、残湯量を少な
くするとともに沸き上り後の熱ロスをできるだけ
排除するようにしたものである。
This invention attempts to eliminate these drawbacks, and stores information on the amount of hot water used in the storage device, for example, in the past.
The amount of hot water used for 10 days is stored as heat value data,
This data is updated every day based on the amount of hot water used that day, that is, it has a learning function.Based on this data, the required time for energizing the heating element is calculated so that the required amount of mixed hot water is always obtained. By controlling the power supply to the body to be leveled over the entire period from the start of the late-night power supply until the end of the supply, the amount of remaining hot water is reduced and heat loss after boiling is eliminated as much as possible. This is how it was done.

以下、この発明の一実施例を第3図の全体構成
図、第4図の制御フローチヤートに基づいて説明
する。
Hereinafter, one embodiment of the present invention will be described based on the overall configuration diagram in FIG. 3 and the control flowchart in FIG. 4.

第3図において、符号1〜5,7,8は第1
図、第2図と同じものを示す。9はサーミスタな
どの温度検出手段(以下温度センサという)で、
貯湯タンク1内に給水管2より給水された水の温
度を連続的に検知するとともに、沸き上りの湯の
温度も検知するものであり、貯湯タンク1の下部
に設けてある。なお、この温度センサ9は水の温
度と湯の温度をそれぞれ検出するよう別個に設け
てもよい。10は前記発熱体5への通電を制御す
るスイツチで、この例ではタイムスイツチ8のオ
ン時には閉じ、後述の制御部の操作により開とな
る。11は前記した制御部で、記憶装置12、演
算装置13、通電率制御装置14、使用熱量演算
装置15および通電制御装置16からなる。17
は前記給水管2に設けた量水器で、貯湯タンク1
への給水流量を計測する。これには、例えば流量
に応じて回動する計量用プロペラにエンコーダを
取り付け、流量に応じたパルス数を発生するもの
が用いられる。なお、量水器17は給湯管3側に
設けてもよい。
In Fig. 3, symbols 1 to 5, 7, and 8 are the first
Figure 2 shows the same thing as Figure 2. 9 is a temperature detection means such as a thermistor (hereinafter referred to as a temperature sensor);
It continuously detects the temperature of water supplied into the hot water storage tank 1 from the water supply pipe 2, and also detects the temperature of boiling hot water, and is provided at the bottom of the hot water storage tank 1. Note that this temperature sensor 9 may be provided separately to detect the temperature of water and the temperature of hot water, respectively. Reference numeral 10 denotes a switch for controlling the supply of electricity to the heating element 5. In this example, it is closed when the time switch 8 is turned on, and is opened by the operation of a control section, which will be described later. Reference numeral 11 denotes the above-mentioned control unit, which includes a storage device 12, a calculation device 13, an energization rate control device 14, a used heat amount calculation device 15, and an energization control device 16. 17
is a water meter installed in the water supply pipe 2, which is connected to the hot water storage tank 1.
Measure the water supply flow rate to. For this purpose, for example, an encoder is attached to a metering propeller that rotates in accordance with the flow rate to generate a number of pulses in accordance with the flow rate. Note that the water meter 17 may be provided on the hot water supply pipe 3 side.

記憶装置12は、使用熱量演算装置15で演算
された使用湯量の熱量を、その数日分の実績KG
をデータとして記憶しておく。このデータは、例
えば10日というように固定日数とし、常に最新デ
ータを保存するようにする。
The storage device 12 stores the heat value of the amount of hot water used calculated by the heat amount used calculation device 15, and records the result KG for several days.
is stored as data. This data should be stored for a fixed number of days, such as 10 days, so that the latest data is always saved.

演算装置13は、例えば記憶装置12からその
内に記憶されているデータ中(上記の例では10日
間のうち)最大値KGmaxを呼び出し、余裕率を
見た定数C(例えば、余裕率10%の場合は1.1とな
る)を乗じて、貯湯タンク1内に貯えておく所要
熱量Ks(kcal)を、 Ks=KGmax×C として算出する。
The arithmetic unit 13 calls, for example, the maximum value KGmax of the data stored therein (for 10 days in the above example) from the storage device 12, and calculates a constant C (for example, a margin rate of 10%) based on the margin rate. 1.1) to calculate the required amount of heat Ks (kcal) to be stored in the hot water storage tank 1 as Ks=KGmax×C.

さらに、演算装置13は、貯湯タンク容量Vt
()、所要熱量Ks(kcal)、および給水温度Ti
(℃)から、沸き上り温度To(℃)を下式から求
める。
Furthermore, the arithmetic unit 13 calculates the hot water storage tank capacity Vt
(), required amount of heat Ks (kcal), and water supply temperature Ti
(°C), calculate the boiling temperature To (°C) using the formula below.

To=Ks/Vt+Ti さらに、演算装置13は発熱体5の通電電力Q
(KW)を設定する。すなわち、深夜電力供給時
間帯は8時間なので、 Q=Ks/8×860 となる。
To=Ks/Vt+Ti Furthermore, the arithmetic unit 13 calculates the energizing power Q of the heating element 5.
(KW). In other words, since the late-night power supply period is 8 hours, Q=Ks/8×860.

通電率制御装置14は、演算装置13で求めた
通電電力Q(KW)になるように、発熱体5への
電力を制御する。これには、例えばトライアツク
を用い、そのゲートを位相制御することにより行
う。
The energization rate control device 14 controls the power to the heating element 5 so that the energization power Q (KW) obtained by the arithmetic device 13 is obtained. This is done by using, for example, a triax and controlling the phase of its gate.

使用熱量演算装置15は、量水器17による使
用湯量をv()、給水温度をTi(℃)、前日の沸
き上り温度をTo(℃)とすると、前日の使用熱量
KGを、 KG=v×(To−Ti) として求める。
The amount of heat used calculation device 15 calculates the amount of heat used on the previous day, assuming that the amount of hot water used by the water meter 17 is v (), the temperature of the water supply is Ti (℃), and the previous day's boiling temperature is To (℃).
Find KG as KG=v×(To−Ti).

通電制御装置16は、温度センサ9が検出した
温度が、沸き上り温度Toに達したときスイツチ
10をオフとするものである。
The energization control device 16 turns off the switch 10 when the temperature detected by the temperature sensor 9 reaches the boiling temperature To.

次に第3図の実施例の動作について第4図を参
照して説明する。なお、第4図の(1)〜(14)は各
ステツプを表わす。
Next, the operation of the embodiment shown in FIG. 3 will be explained with reference to FIG. 4. Note that (1) to (14) in FIG. 4 represent each step.

スタートし(1)、1日の湯の使用が終つた時点、
すなわち、電気温水器に深夜電力が供給されるま
でに当日の使用湯量に対する使用熱量KGが、使
用熱量演算装置15によつて求められ(2)、このデ
ータが記憶装置12へ入力されて、あらかじめ貯
えられたデータが更新される(3)。
When you start (1) and finish using the hot water for the day,
That is, before midnight power is supplied to the electric water heater, the amount of heat KG used for the amount of hot water used that day is determined by the amount of heat used calculation device 15 (2), and this data is input into the storage device 12 and stored in advance. The stored data is updated (3).

したがつて、深夜、例えば23時になるとタイム
スイツチ8がオンする(4)。この通電と同時に制御
が開始されると、まず、記憶装置12から最新の
データのうち最大のものKGmaxを呼び出し(5)、
演算装置13において、KGmaxに余裕率を見た
定数Cを乗じて所要熱量Ksを設定する(6)。また、
同時に温度センサ9によつて貯湯タンク1内の給
水温度Tiを測定し(7)、さらに、演算装置13に
おいて通電電力Q(KW)を求め、次いで、通電
時間Hs、給水温度Ti、貯湯タンク容量Vt、所要
熱量Ksから沸き上り温度Toを算出し設定する
(8)。
Therefore, at midnight, for example at 23:00, the time switch 8 is turned on (4). When control is started at the same time as this energization, first, the largest KGmax of the latest data is called from the storage device 12 (5),
In the arithmetic unit 13, the required amount of heat Ks is set by multiplying KGmax by a constant C based on the margin rate (6). Also,
At the same time, the temperature sensor 9 measures the water supply temperature Ti in the hot water storage tank 1 (7), and the arithmetic unit 13 calculates the energizing power Q (KW), and then calculates the energization time Hs, the water supply temperature Ti, and the hot water tank capacity. Calculate and set the boiling temperature To from Vt and the required heat amount Ks
(8).

このようにして得られた通電電力Q(KW)の
データを通電率制御装置14に入力すると、深夜
電力の供給時間内での発熱体5に供給される単位
時間あたりの平均電力が算出され通電率が定めら
れ(9)、発熱体5に通電される(10)。そして、湯温が
あらかじめ設定された沸き上り温度Toに達する
と(11)、通電制御装置16が動作してスイツチ10
をオフとして発熱体5への通電をオフとする(12)。
When the data of the energized power Q (KW) obtained in this way is inputted to the energization rate control device 14, the average power per unit time supplied to the heating element 5 during the late night power supply time is calculated and energized. The rate is determined (9), and the heating element 5 is energized (10). When the water temperature reaches the preset boiling temperature To (11), the energization control device 16 operates and the switch 10 is activated.
is turned off to turn off the power to the heating element 5 (12).

さらに、深夜電力供給時間終了時刻、例えば7
時になると、タイムスイツチ8がオフとなり
(13)、シーケンスはストツプとなる(14)。
Furthermore, the late-night power supply time end time, for example, 7
When the time comes, the time switch 8 is turned off (13) and the sequence is stopped (14).

なお、上記の実施例では演算装置13で所要熱
量Ksの算出に、記憶装置12内のデータ中、最
大のKGmaxを利用したが、この他、固定日数中
の平均を用いたり、他のデータを用いてもよい。
また、制御部11として中央処理装置(CPU)
を備えたマイクロコンピユータを用いることがで
きる。
In the above embodiment, the calculation unit 13 uses the maximum KGmax of the data in the storage device 12 to calculate the required amount of heat Ks, but in addition, the average over a fixed number of days or other data may be used. May be used.
In addition, a central processing unit (CPU) is used as the control unit 11.
A microcomputer can be used.

以上詳細に説明したように、この発明は記憶装
置に過去の実績として使用湯量に対する熱量の最
新のデータを貯えておき、このデータに基づいて
発熱体に供給する電力量を決定するようにし、か
つ、電力の供給を深夜電力供給帯の全体に亘つて
平準化して行うようにしたので、使用者の実状に
応じた湯量が毎日得られるので、残湯量が少なく
なり、したがつて、沸き上り後の放熱ロスが減少
して維持費が安くなる。また、記憶装置のデータ
は毎回更新される。つまり学習機能を有するの
で、日々変化する湯の使用量に十分対応すること
ができる利点を有する。
As explained in detail above, the present invention stores the latest data on the amount of heat relative to the amount of hot water used as past results in a storage device, and determines the amount of electric power to be supplied to the heating element based on this data. Since the electric power supply is leveled over the entire late-night power supply zone, the amount of hot water that is available every day according to the actual situation of the user is reduced, and the amount of hot water left after boiling is reduced. Reduces heat loss and reduces maintenance costs. Furthermore, the data in the storage device is updated every time. In other words, since it has a learning function, it has the advantage of being able to adequately respond to the daily changing amount of hot water used.

【図面の簡単な説明】[Brief explanation of drawings]

第1図は一般的な貯湯式電気温水器の構成図、
第2図は従来の貯湯式電気温水器における主要電
気回路図、第3図はこの発明の一実施例を示す全
体構成図、第4図は同じくその制御フローチヤー
トを示す。 図中、1は貯湯タンク、2は給水管、3は給湯
管、4は出湯栓、5は発熱体、7は電源、8はタ
イムスイツチ、9は温度センサ、10はスイツ
チ、11は制御部、12は記憶装置、13は演算
装置、14は通電率制御装置、15は使用熱量演
算装置、16は通電制御装置、17は量水器であ
る。なお、図中の同一符号は同一または相当部分
を示す。
Figure 1 is a configuration diagram of a typical hot water storage type electric water heater.
FIG. 2 is a main electrical circuit diagram of a conventional hot water storage type electric water heater, FIG. 3 is an overall configuration diagram showing an embodiment of the present invention, and FIG. 4 is a control flow chart thereof. In the figure, 1 is a hot water storage tank, 2 is a water supply pipe, 3 is a hot water supply pipe, 4 is a hot water tap, 5 is a heating element, 7 is a power supply, 8 is a time switch, 9 is a temperature sensor, 10 is a switch, and 11 is a control unit , 12 is a storage device, 13 is a calculation device, 14 is an energization rate control device, 15 is a used heat amount calculation device, 16 is an energization control device, and 17 is a water meter. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

【特許請求の範囲】[Claims] 1 深夜電力を利用して発熱体に通電し貯湯タン
ク内の水を加熱する電気温水器において、過去の
複数日の使用湯量の実績を熱量のデータとして貯
えておく記憶装置と、前記データに基づいて前記
貯湯タンク内に貯えておく所要熱量と前記発熱体
への通電電力を算出する演算装置と、前記通電電
力を深夜電力通電時間帯に平均して供給するため
の通電率制御装置と、使用した熱量を算出しその
値を前記記憶装置へ入力して前記データの更新を
行わせる使用熱量演算装置とを具備せしめたこと
を特徴とする貯湯式電気温水器の制御装置。
1. In an electric water heater that heats water in a hot water storage tank by energizing a heating element using late-night electricity, there is a storage device that stores the amount of hot water used over multiple days in the past as heat amount data, and a an arithmetic device for calculating the required amount of heat to be stored in the hot water storage tank and the power to be applied to the heating element; 1. A control device for a hot water storage type electric water heater, comprising: a used heat amount calculation device that calculates the amount of heat generated and inputs the value into the storage device to update the data.
JP58140808A 1983-08-01 1983-08-01 Control device of hot-water storage type electric hot- water heater Granted JPS6030940A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP58140808A JPS6030940A (en) 1983-08-01 1983-08-01 Control device of hot-water storage type electric hot- water heater

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP58140808A JPS6030940A (en) 1983-08-01 1983-08-01 Control device of hot-water storage type electric hot- water heater

Publications (2)

Publication Number Publication Date
JPS6030940A JPS6030940A (en) 1985-02-16
JPH026980B2 true JPH026980B2 (en) 1990-02-14

Family

ID=15277215

Family Applications (1)

Application Number Title Priority Date Filing Date
JP58140808A Granted JPS6030940A (en) 1983-08-01 1983-08-01 Control device of hot-water storage type electric hot- water heater

Country Status (1)

Country Link
JP (1) JPS6030940A (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6252360A (en) * 1985-09-02 1987-03-07 Becker Kk Control device for filling hot-water into hot-water reserving type electric water heater

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS57202446A (en) * 1981-06-05 1982-12-11 Omron Tateisi Electronics Co Controlling device of water heater using midnight electric power supply
JPS58142145A (en) * 1982-02-17 1983-08-23 Hasegawa Komuten Co Ltd Electric water heater utilizing midnight powor supply

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS57202446A (en) * 1981-06-05 1982-12-11 Omron Tateisi Electronics Co Controlling device of water heater using midnight electric power supply
JPS58142145A (en) * 1982-02-17 1983-08-23 Hasegawa Komuten Co Ltd Electric water heater utilizing midnight powor supply

Also Published As

Publication number Publication date
JPS6030940A (en) 1985-02-16

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