CN111623521A - Electric continuous heater and method for operating an electric continuous heater of this type - Google Patents

Electric continuous heater and method for operating an electric continuous heater of this type Download PDF

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Publication number
CN111623521A
CN111623521A CN202010129092.9A CN202010129092A CN111623521A CN 111623521 A CN111623521 A CN 111623521A CN 202010129092 A CN202010129092 A CN 202010129092A CN 111623521 A CN111623521 A CN 111623521A
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CN
China
Prior art keywords
control electronics
display device
display
voltage
continuous heater
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.)
Pending
Application number
CN202010129092.9A
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Chinese (zh)
Inventor
C.科克
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.)
Golders Holdings Co ltd
Gerdes Holding GmbH and Co KG
Original Assignee
Golders Holdings Co ltd
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 Golders Holdings Co ltd filed Critical Golders Holdings Co ltd
Publication of CN111623521A publication Critical patent/CN111623521A/en
Pending legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H9/00—Details
    • F24H9/20—Arrangement or mounting of control or safety devices
    • F24H9/2007—Arrangement or mounting of control or safety devices for water heaters
    • F24H9/2014—Arrangement or mounting of control or safety devices for water heaters using electrical energy supply
    • F24H9/2028—Continuous-flow heaters
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H1/00—Water heaters, e.g. boilers, continuous-flow heaters or water-storage heaters
    • F24H1/10—Continuous-flow heaters, i.e. heaters in which heat is generated only while the water is flowing, e.g. with direct contact of the water with the heating medium
    • F24H1/101—Continuous-flow heaters, i.e. heaters in which heat is generated only while the water is flowing, e.g. with direct contact of the water with the heating medium using electric energy supply
    • F24H1/102—Continuous-flow heaters, i.e. heaters in which heat is generated only while the water is flowing, e.g. with direct contact of the water with the heating medium using electric energy supply with resistance
    • F24H1/103—Continuous-flow heaters, i.e. heaters in which heat is generated only while the water is flowing, e.g. with direct contact of the water with the heating medium using electric energy supply with resistance with bare resistances in direct contact with the fluid
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H15/00—Control of fluid heaters
    • F24H15/10—Control of fluid heaters characterised by the purpose of the control
    • F24H15/124—Preventing or detecting electric faults, e.g. electric leakage
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H15/00—Control of fluid heaters
    • F24H15/20—Control of fluid heaters characterised by control inputs
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H15/00—Control of fluid heaters
    • F24H15/30—Control of fluid heaters characterised by control outputs; characterised by the components to be controlled
    • F24H15/355—Control of heat-generating means in heaters
    • F24H15/37—Control of heat-generating means in heaters of electric heaters
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H15/00—Control of fluid heaters
    • F24H15/30—Control of fluid heaters characterised by control outputs; characterised by the components to be controlled
    • F24H15/395—Information to users, e.g. alarms
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H15/00—Control of fluid heaters
    • F24H15/40—Control of fluid heaters characterised by the type of controllers
    • F24H15/414—Control of fluid heaters characterised by the type of controllers using electronic processing, e.g. computer-based
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H9/00—Details
    • F24H9/18—Arrangement or mounting of grates or heating means
    • F24H9/1809—Arrangement or mounting of grates or heating means for water heaters
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H9/00—Details
    • F24H9/20—Arrangement or mounting of control or safety devices
    • F24H9/2007—Arrangement or mounting of control or safety devices for water heaters

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Computer Hardware Design (AREA)
  • Control Of Resistance Heating (AREA)
  • Control Of Indicators Other Than Cathode Ray Tubes (AREA)
  • Heat-Pump Type And Storage Water Heaters (AREA)

Abstract

The invention relates to an electronic continuous heater for heating a liquid, comprising: an electrically heatable heating channel assembly having at least one electrical heating element; control electronics comprising at least one microprocessor (10), said control electronics being provided for electrically operating the heating element; a display device (12) which is in connection with the aid of the control electronics and is characterized in that the display device (12) is constructed as a bistable digital display such that the display content remains visible even in the absence of a display supply voltage of the display device (12).

Description

Electric continuous heater and method for operating an electric continuous heater of this type
Technical Field
The present invention relates to an electronic continuous heater for heating a liquid, comprising: an electrically heatable heating channel assembly having at least one electrical heating element; control electronics comprising at least one microprocessor, which are provided for electrically actuating the heating element, and a display device connected thereto by means of the control electronics. The invention further relates to a method for operating such an electric continuous heater.
Background
A control and safety device for a continuous heater is known from DE 4416798 a 1. These documents disclose control devices provided with a voltage monitoring mechanism, which determine in a known manner the overvoltage or undervoltage of the supply voltage. The voltage monitoring mechanism is also connected to the RESET input of the microcontroller to cause the control device to RESET when a threshold value of the supply voltage is determined.
Although in this way the control device or the control electronics are reset into a defined state in the event of an undervoltage, it is generally possible, when a reset of the control electronics is carried out, for the connected display or display device to carry out the reset and thus to lose the previously displayed display content. After such an undervoltage event, it is no longer recognizable to the user, user or professional after the fact, for which reason a reset was carried out or why the continuous heater was not in a state of proper operation.
Disclosure of Invention
The object of the present invention is therefore to provide a continuous heater which displays information about the state of the respective device even in the currentless or mains voltage-free state. Furthermore, it is an object of the invention to provide a continuous heater which, in the event of undervoltage, provides an indication of an undervoltage and/or a fault event occurring. The invention is based on the object of specifying a corresponding method for operating such a continuous heater.
This object is achieved by an assembly having the features mentioned at the outset in that the display device is designed as a bistable digital display, so that the display content remains visible even in the absence of a display supply voltage of the display device. It is thus advantageously achieved that the display device of the continuous heater according to the invention always displays the display content even in the currentless or mains voltage-free state. In addition, the presence of an undervoltage can be detected on the continuous heater in this way for the user and/or the professional. In this way, such fault states can always be detected directly on the display of the display device and are independent of whether the continuous heater is supplied with the mains voltage as intended. According to an alternative embodiment of the invention, the display device is designed to display the display content also in grayscale or in color. Here, the display devices are respectively arranged such that the display content remains unchanged even in the currentless state of the display devices.
An advantageous development of the invention is characterized in that the display surface of the display device is formed by electronic paper. This provides the advantage that the display device always has to be written (beschreiben) only when the corresponding display content should be changed. Furthermore, the display content respectively finally written into the display device also remains visible when the display device is no longer supplied with the display supply voltage.
According to an advantageous further development, it is provided that the control electronics have at least one electrical energy store for buffering the operating voltage of the control electronics and that the control electronics have an undervoltage detection circuit for detecting an undervoltage of the mains voltage and/or of the heating element voltage. Advantageously, the operating voltage of the control electronics is maintained at least temporarily (even in the event of an undervoltage), so that the display device can be written with display content which gives information about the type of undervoltage occurring or the type of fault. Furthermore, the control electronics can thus be brought into a defined state before the supply voltage of the control electronics finally collapses.
A preferred embodiment of the invention is characterized in that the control electronics are provided to cause the display device to output an undervoltage notification if an undervoltage is detected by means of the undervoltage detection circuit. This offers the advantage that a corresponding undervoltage event can be recognized on its display even in the currentless state of the continuous heater.
The object is furthermore achieved by a corresponding method having the features mentioned at the outset, in which the display device is operated as a bistable digital display by means of a control device in such a way that the display content remains visible even in the absence of a display supply voltage of the display device.
According to an advantageous embodiment of the invention, the operating voltage of the control electronics is buffered by means of the control electronics and an undervoltage of the mains voltage and/or the heating element voltage is detected by means of an undervoltage detection circuit of the control electronics.
An advantageous embodiment is characterized in that, in the event of an undervoltage being detected by means of the undervoltage detection circuit, the control electronics cause the display device to output an undervoltage notification.
According to a further advantageous embodiment, it is provided that the control device is prompted on the factory side to write a display device with display content for marking the technical test performed on the continuous heater, before the continuous heater is switched to currentless after the test is completed. In this way, by means of the display device, it can be recognized, in particular in the currentless state of the continuous heater, whether the required technical functional check of the continuous heater has been successfully completed on the plant side. In addition, it can be recognized that this is a new device.
The advantages associated with the method according to the invention have been explained in detail in connection with the continuous heater according to the invention, which is incorporated herein by reference.
Drawings
Further preferred and/or expedient features and embodiments of the invention emerge from the dependent claims and the description. Particularly preferred embodiments are explained in detail with the aid of the drawings. Shown in the attached drawings:
figure 1 shows a block diagram of the control electronics of a continuous heater according to the invention,
figure 2 shows a flow chart of the way in which the control electronics or the method according to the invention functions,
figure 3 illustrates an exemplary first display,
FIG. 4 shows exemplary second display content, an
Fig. 5 illustrates an exemplary third display content.
Detailed Description
Fig. 1 shows a block diagram of the control electronics of a continuous heater according to the invention. The continuous heater, which is not shown in the figures, comprises an electrically heatable heating channel assembly having at least one electric heating element, which is preferably arranged as a bare wire heating coil. The control electronics comprise at least one microprocessor 10, which is provided for electrically actuating the heating element. For this purpose, the control device is electrically connected to power electronics 11, which are provided for switching the electric heating element on and off and for controlling its heating power. Such power electronics are sufficiently well known and will therefore not be described in detail here.
The control electronics are electrically connected to the display device 12. As shown in fig. 1, display device 12 is preferably electrically connected to microprocessor 10. The display device 12 is here constructed as a bistable digital display. The display content written once onto the display by means of the control electronics remains visible in this way even in the absence of the display supply voltage of the display device 12. Thus, writing to the display device 12 is always only required when the changed display content should be displayed.
Preferably, the display surface of the display device 12 is formed of electronic paper. In other words, the display device 12 is configured as an electronic paper display. The display device 12 is thus constructed as a passive display in which display content, such as text and/or graphics, is continuously displayed without the display supply voltage being present for this purpose. The display content displayed once is maintained for a long time even in the absence of a display supply voltage until a rewriting access is effected with different display contents by the control electronics.
Advantageously, the control electronics comprise at least one electrical energy accumulator 13 for buffering the operating voltage of the control electronics. The energy accumulator 13 preferably comprises at least one supercapacitor (english: supercapacitor) or an ultracapacitor. In the event of an undervoltage of the mains voltage or in the event of a phase failure, the energy store 13 serves as an intermediate storage in order to supply the control electronics with energy for a sufficiently long time in order to be able to carry out the required control steps before the operating voltage of the control electronics also becomes too low.
Furthermore, the control electronics comprise an undervoltage detection circuit for detecting or detecting an undervoltage of the mains voltage and/or of the heating element voltage. For this purpose, the microprocessor 10 of the control circuit is connected to the power electronics via an electrical line 14, via which the microprocessor 10 is supplied with signals for querying the mains voltage and/or the heating element voltage. The lines 14 and 15 shown in fig. 1 are used to symbolize the connection of the components to each other. The lines 14, 15 may be physically embodied as electrical signal lines or as a bus system.
The control electronics are further arranged to cause the display device to output an undervoltage notification in the event of an undervoltage being identified by means of the undervoltage detection circuit. The procedure when an/the undervoltage is detected is explained below with reference to the flow chart in fig. 2. If the undervoltage detection circuit detects in step 15 that the system voltage and/or the supply voltage of the power electronics is less than a predefined minimum voltage, the voltage supply of the control circuit, which includes the microprocessor 10 and the display device 12, is first ensured via the energy store 13. The energy store 13 optionally comprises the required circuit components in order to automatically switch to the supply by means of the energy store 13 in the event of a failure of the normal supply voltage of the control electronics. The handover is performed in step 16.
In step 17, the display device 12 is written with a display content that informs of the type of undervoltage. If it is determined by means of the undervoltage detection circuit that one of the undervoltage or grid phases is defective, the display device 12 is written, for example, with the display shown in fig. 3. If an undervoltage of the supply voltage of the heating element is determined by means of the undervoltage detection circuit, a display, for example, as shown in fig. 4, is output by means of the display device 12.
It is further preferred that the microprocessor 10 and the display device 12 are then placed in a "deep sleep mode" in step 18.
The method according to the invention has been explained in detail in connection with the above-described device according to the invention, so that, in order to avoid repetition, only selected aspects of the method according to the invention are discussed in more detail below.
The method according to the invention is used for operating the aforementioned electric continuous heater. The electrical actuation of the at least one electrical heating element is effected by means of a control device. The display device 12 is operated as a bistable digital display by means of a control device. This means that the display content is each written into the display device 12 only once by the microprocessor 10, since the display device 12-independently of whether the display supply voltage is supplied to it-holds the display content written once by means of the microprocessor. The display content thus remains visible at all times even in the absence of the display supply voltage of the display device 12.
After the continuous heater has passed all the necessary tests for technical functional capability and quality assurance on the test stand in the production line, the display device 12 is preferably written on the factory side with the third display shown in fig. 5. In other words, it is prompted on the factory side that the display device 12 is written with display content, i.e. the third mentioned display content, by means of the control device, which is used to mark the technical test performed of the continuous heater, before the continuous heater is switched to currentless after the test is completed. Advantageously, the mentioned display content is also kept in the currentless state. If the continuous heater is removed from its packaging, the installer can read directly on the display device 12 that he has obtained a new device that has been inspected and is in a defect free state. The control device is further preferably designed to display this third display content by means of the display device 12 only after the mentioned test has been successfully carried out. After the first commissioning is completed, the third display content is no longer displayed in any operational state.

Claims (8)

1. An electronic continuous heater for heating a liquid, comprising:
an electrically heatable heating channel assembly having at least one electrical heating element;
control electronics comprising at least one microprocessor (10), said control electronics being provided for electrically operating the heating element;
by means of a display device (12) in connection with the control electronics,
it is characterized in that the preparation method is characterized in that,
the display device (12) is configured as a bistable digital display such that the display content remains visible even in the absence of a display supply voltage of the display device (12).
2. Continuous heater according to claim 1, characterised in that the display surface of the display device (12) is formed by electronic paper.
3. Continuous heater according to claim 1 or 2, in which the control electronics have at least one electrical energy accumulator (13) for buffering the operating voltage of the control electronics, and the control electronics have an undervoltage detection circuit for detecting undervoltages of the mains voltage and/or of the heating element voltage.
4. Continuous heater according to claim 3, in which the control electronics are arranged to cause the display device (12) to output an under-voltage notification if an under-voltage is identified by means of the under-voltage detection circuit.
5. Method for operating an electronic continuous heater for heating a liquid, wherein the continuous heater comprises an electrically heatable heating channel assembly with at least one electric heating element, control electronics comprising at least one microprocessor (10) and a display device (12) in connection by means of the control electronics, the method comprising:
electrically actuating the at least one electric heating element by means of the control device,
it is characterized in that the preparation method is characterized in that,
the display device (12) as a bistable digital display is actuated by means of the control device in such a way that the display content remains visible even in the absence of a display supply voltage of the display device (12).
6. Method according to claim 5, characterized in that the operating voltage of the control electronics is buffered by means of the control electronics, and
an undervoltage of the mains voltage and/or of the heating element voltage is detected by means of an undervoltage detection circuit of the control electronics.
7. Method according to claim 6, characterized in that in case of an under-voltage being identified by means of the under-voltage detection circuit, the display device (12) is caused to output an under-voltage notification by means of the control electronics.
8. Method according to any of claims 5 to 7, characterized in that the control device is prompted at the factory side to write the display device (12) with the display content for marking the performed technical test of the continuous heater before the continuous heater is switched to no current after the test is completed.
CN202010129092.9A 2019-02-28 2020-02-28 Electric continuous heater and method for operating an electric continuous heater of this type Pending CN111623521A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP19160106.1 2019-02-28
EP19160106.1A EP3702694B1 (en) 2019-02-28 2019-02-28 Electronic continuous flow heater and method for operating same

Publications (1)

Publication Number Publication Date
CN111623521A true CN111623521A (en) 2020-09-04

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CN202010129092.9A Pending CN111623521A (en) 2019-02-28 2020-02-28 Electric continuous heater and method for operating an electric continuous heater of this type

Country Status (4)

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US (1) US20200278134A1 (en)
EP (1) EP3702694B1 (en)
CN (1) CN111623521A (en)
PL (1) PL3702694T3 (en)

Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4588989A (en) * 1983-02-22 1986-05-13 Mitutoyo Mfg. Co., Ltd. Supervisory device for wrong operation of varying quantity measuring apparatus
ATA30489A (en) * 1989-02-13 1991-06-15 Vaillant Gmbh FUEL HEATED DEVICE, e.g. WATER HEATER
DE4416798A1 (en) * 1994-05-07 1995-11-16 Clage Gmbh Electronic control and safety device for through-flow water heater
TW512920U (en) * 2001-11-13 2002-12-01 Pauden Scient & Amp Technologi Circuit capable of automatic disconnection under low battery voltage in a water heater
CN2567588Y (en) * 2002-08-17 2003-08-20 中国科学院长春光学精密机械与物理研究所 Testing instrument for display performance of liquid crystal display
US20050040250A1 (en) * 2003-08-18 2005-02-24 Wruck Richard A. Transfer of controller customizations
JP2010139751A (en) * 2008-12-11 2010-06-24 Sharp Corp Information display and information display method
US9263156B2 (en) * 2013-11-07 2016-02-16 Sandisk Enterprise Ip Llc System and method for adjusting trip points within a storage device
US20170059193A1 (en) * 2014-04-25 2017-03-02 Somfy Sas Device and a system for control and/or command
EP3190351A1 (en) * 2016-01-06 2017-07-12 Vaillant GmbH Heating display
CN107872212A (en) * 2016-09-26 2018-04-03 英飞凌科技股份有限公司 Control method, Power switching devices and switching device
US20180119988A1 (en) * 2016-10-27 2018-05-03 Stiebel Eltron Gmbh & Co. Kg Tankless Water Heater and Method of Controlling a Tankless Water Heater
CN109099585A (en) * 2018-08-27 2018-12-28 珠海格力电器股份有限公司 Air energy water heater thermo-electric generation control system, water heater and its control method

Patent Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4588989A (en) * 1983-02-22 1986-05-13 Mitutoyo Mfg. Co., Ltd. Supervisory device for wrong operation of varying quantity measuring apparatus
ATA30489A (en) * 1989-02-13 1991-06-15 Vaillant Gmbh FUEL HEATED DEVICE, e.g. WATER HEATER
DE4416798A1 (en) * 1994-05-07 1995-11-16 Clage Gmbh Electronic control and safety device for through-flow water heater
TW512920U (en) * 2001-11-13 2002-12-01 Pauden Scient & Amp Technologi Circuit capable of automatic disconnection under low battery voltage in a water heater
CN2567588Y (en) * 2002-08-17 2003-08-20 中国科学院长春光学精密机械与物理研究所 Testing instrument for display performance of liquid crystal display
US20050040250A1 (en) * 2003-08-18 2005-02-24 Wruck Richard A. Transfer of controller customizations
JP2010139751A (en) * 2008-12-11 2010-06-24 Sharp Corp Information display and information display method
US9263156B2 (en) * 2013-11-07 2016-02-16 Sandisk Enterprise Ip Llc System and method for adjusting trip points within a storage device
US20170059193A1 (en) * 2014-04-25 2017-03-02 Somfy Sas Device and a system for control and/or command
EP3190351A1 (en) * 2016-01-06 2017-07-12 Vaillant GmbH Heating display
CN107872212A (en) * 2016-09-26 2018-04-03 英飞凌科技股份有限公司 Control method, Power switching devices and switching device
US20180119988A1 (en) * 2016-10-27 2018-05-03 Stiebel Eltron Gmbh & Co. Kg Tankless Water Heater and Method of Controlling a Tankless Water Heater
CN109099585A (en) * 2018-08-27 2018-12-28 珠海格力电器股份有限公司 Air energy water heater thermo-electric generation control system, water heater and its control method

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US20200278134A1 (en) 2020-09-03
PL3702694T3 (en) 2023-10-30
EP3702694A1 (en) 2020-09-02
EP3702694B1 (en) 2023-06-07

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