CN2724272Y - General electricity proof wall device for electric heating water boiler controlled by monolithic computer - Google Patents

Abstract

The utility model relates to an electricity preventing wall device for electric heating boiling water heaters, which is controlled by a single-chip microcomputer and belongs to the technology application field of the single-chip microcomputer, particularly the electricity preventing wall technology which can protect personal safety when an earth wire and the basic insulation of the electric heating boiling water heater fail simultaneously. The utility model is composed of a null earth wire electrical potential difference detecting device, a central processing unit and a relay executive circuit which are connected in order. The utility model is characterized in that a transformer or a resistance-capacity pressure reducing circuit is arranged between the earth wire and the null wire, and I/O input ports of the single-chip microcomputer are connected through a switching tube. The single-chip microcomputer receives the voltage difference signals between the null wire and the earth wire, and the earth and the power supply of the electric heating boiling water heater are cut off in real time when the earth wire is provided with electricity. The utility model is suitable for every controlling way of every kind of electric heating boiling water heater, and the aim of the electricity preventing wall technology provided by the utility model is to protect the personal safety under the condition of unreliable earthing or failed earth wire.

Description

The general electricity-preventing wall device of monolithic processor controlled electrothermal water boiling stove

Anti-electric wall technology when technical field the invention belongs to microchip technology field and is particularly related to electrothermal water boiling stove ground wire and basic insulation and lost efficacy simultaneously.

Background technology is well-known, and it must be reliably that electrothermal water boiling stove product standard requires the ground connection in the user family, and the standard plug that the band ground wire also is housed in its product is for linking to each other good with assurance ground connection with ground wire in the socket.And in China, power utilization environment is poor, and the ground connection of many buildings is insecure, or even lack.In this case, qualified electrothermal water boiling stove can not guarantee user's safety.The anti-electric wall technology that the invention relates to is special in China's actual conditions, is intended to guarantee under unsafe power utilization environment user's safety.And before the invention applying date, the electrothermal water boiling stove does not have the personal safety protector that cut off ground wire and electrothermal water boiling stove power supply when ground wire and basic insulation lost efficacy simultaneously in real time, brings potential safety hazard for the user who does not have good earth.

The purpose of summary of the invention the invention is exactly to overcome the shortcoming that the above-mentioned prior art of electrothermal water boiling stove exists, providing a kind of had when this electrothermal water boiling stove ground wire and basic insulation lost efficacy simultaneously, can cut off the power supply of ground wire and electrothermal water boiling stove in real time, even under dangerous power utilization environment, also can guarantee user's safety.The relay circuit of the invention guarantees that simultaneously the electrothermal water boiling stove recovers or do not influence normal use when ground wire is not charged.

The invention solves the technical scheme that its technical problem adopts: the invention is provided with cross-over connection in ground wire E _INAnd the potential difference detecting device between zero line N (1), this device provides ground wire normal or charged logical signal to central processing unit (2) I/O input port, and central processing unit (2) is by the break-make of I/O output port control relay executive circuit.Relay executive circuit (3) is by drive circuit Q ₁, Q ₂And relay J ₁, J ₂Form, be serially connected with ground wire E respectively at its normally-closed contact, normally opened contact _IN, E _OUTAnd electrothermal water boiling stove power supply L _IN, L _OUTRelay executive circuit (3) is controlled by central processing unit (2), cuts off being serially connected in relay J when ground wire electrification ₁, J ₂Ground wire and electrothermal water boiling stove power supply.Under normal circumstances, the relay normally-closed contact is guaranteed ground wire E _IN,, E _OUTAnd electrothermal water boiling stove power supply L _IN, L _OUTConnection.

The advantage of the invention is simple in structure, and highly versatile is suitable for all kinds of electrothermal water boiling stoves and installs, and effect is obvious, does not influence the use under the ground wire normal condition, its central processing unit also can with electrothermal water boiling stove single chip machine controlling circuit shared resource.

Description of drawings Fig. 1 is the circuit structure block diagram of the invention.Wherein (1) is that zero grounding potential difference detector set (2) is central processing unit, and (3) carry out the electrothermal water boiling stove for relay.

Fig. 2 is the electrical schematic diagram of the invention.E among the figure _INBe ground wire end of incoming cables, E _OUTBe the ground wire leading-out terminal, promptly link to each other with electrothermal water boiling stove earth terminal; L _INBe live wire end of incoming cables, L _OUTBe the live wire leading-out terminal, promptly link to each other with electrothermal water boiling stove fire line end; N is a zero line, and 12V is the 12V DC power supply.

Embodiment the invention embodiment central processing unit adopts PIC16C54 (PIC16C57) chip microprocessor able to programme, and as previously mentioned, this chip microprocessor can be shared with the single chip machine controlling circuit of electrothermal water boiling stove.Cross-over connection is in zero line N and ground wire E _INBetween potential difference detecting device by transformer T or resistance-capacitance circuit R ₁C ₁(among Fig. 2 shown in the dotted line) step-down, D ₁～D ₄Diode rectification, capacitor C ₀, voltage-stabiliser tube the DW voltage stabilizing circuit and the switching tube Q that form ₀Form switching tube Q ₀Be connected in central processing unit I/O input port, I/O output port control relay executive circuit Q ₁, Q ₂, J ₁, J ₂The relay normally-closed contact connects ground wire E _INAnd E _OUT, normally opened contact connects electrothermal water boiling stove L _INAnd L _OUT

Operation principle summary: the electrothermal water boiling stove under the situation that ground connection and basic insulation lost efficacy simultaneously, zero line N and ground wire E _INBetween voltage between 36V-220V, cross-over connection is in zero line N and ground wire E _INOn transformer reduction voltage circuit or resistance-capacitance depressurization circuit produce the 1.5-6V dc pulse voltage by rectification circuit, make switching tube Q ₀Conducting is to central processing unit output low level signal.Q in the relay executive circuit ₁, Q ₂Be respectively J ₁, J ₂Drive circuit.When the I/O output makes Q ₁Or Q ₂During for low level, the actuating of relay disconnects the ground wire E that is connected on its normally-closed contact _INAnd E _OUTAnd the L of normally opened contact (being normally-closed contact during work) _INAnd L _OUT

Claims (4)

1, the general electricity-preventing wall device of a kind of monolithic processor controlled electrothermal water boiling stove, its principal character is the potential difference detecting device (1) that is provided with between cross-over connection ground wire E and zero line N, this device provides potential difference signal between ground wire and zero line to central processing unit (2) I/O input port, central processing unit (2) cuts off the ground wire E that is connected on the relay normally-closed contact in real time by the break-make of I/O output port control relay executive circuit (3) when ground wire electrification _OUTAnd the power supply L of electrothermal water boiling stove _OUT

2, the general electricity-preventing wall device of monolithic processor controlled electrothermal water boiling stove according to claim 1 is characterized in that cross-over connection is in zero line N and ground wire E _INBetween potential difference detecting device (1) by transformer T or resistance-capacitance circuit R ₁C ₁Step-down, D ₁～D ₄Diode rectification, capacitor C ₀, voltage-stabiliser tube the DW voltage stabilizing circuit and the switching tube Q that form ₀Form switching tube Q when ground wire electrification ₀Provide logical signal (present embodiment is a low level) to central processing unit (2) I/O input port.

3, the general electricity-preventing wall device of monolithic processor controlled electrothermal water boiling stove according to claim 1 is characterized in that (a) central processing unit (2) is a programmable microprocessor; (b) zero line N and ground wire E _INBetween potential difference detecting device (1) output signal connect the I/O input port of central processing unit (2); (c) switching tube Q in the relay executive circuit (3) ₁, Q ₂The I/O output port that is controlled by central processing unit (2), relay J ₁, J ₂Be controlled by switching tube Q ₁, Q ₂And control the break-make of ground wire and electrothermal water boiling stove power supply respectively.

4, the general electricity-preventing wall device of monolithic processor controlled electrothermal water boiling stove according to claim 1, it is characterized in that described central processing unit (2) can be provided with separately also can with the central processing unit shared resource in the electrothermal water boiling stove control circuit.