CN206191933U - Take electric water heater control system of relay fault feedback function - Google Patents

Abstract

The utility model discloses an electric water heater control system with a relay fault feedback function, comprising: a three-pole electric leakage protection plug power cord that can be automatically disconnected and reset, a single-chip microcomputer, an electric heater, and a relay, which are used to realize strong and weak current isolation and An isolated communication module for communication, and a relay feedback circuit; the power line of the three-pole leakage protection plug is connected to the power supply line of the electric water heater; the relay is connected between the power line of the three-pole leakage protection plug and the electric heater; The single-chip microcomputer is connected with the relay signal through the drive circuit to control the pull-in or disconnection of the relay; the isolated communication module is connected with the single-chip microcomputer and the three-pole leakage protection plug power line signal; the relay feedback circuit is connected between the relay and the single-chip microcomputer . When the relay fails to be disconnected normally during use, it will automatically cut off the power supply of the electric water heater to ensure the safety of users.

Description

A Control System of Electric Water Heater with Relay Fault Feedback Function

technical field

The utility model relates to the technical field of electric hot water control, in particular to an electric water heater control system with relay fault feedback function.

Background technique

In the prior art, the pull-in or disconnection of the relay is realized by controlling the driving circuit of the single-chip microcomputer, and the electric heater is connected to the input and output terminals of the relay. with off. However, when the load is switched on instantaneously, an inrush current several times higher than the working current will be generated. The inrush current will easily cause the contacts of the relay to melt and stick, causing the load to be uncontrolled and unable to be disconnected normally, posing a safety hazard.

Utility model content

Aiming at the problems existing in the prior art, the purpose of the utility model is to provide an electric water heater control system with good safety and relay fault feedback function.

In order to achieve the above object, the utility model adopts the following technical solutions.

An electric water heater control system with a relay fault feedback function is characterized in that it includes: a three-pole leakage protection plug power cord that can be automatically disconnected and reset, a single-chip microcomputer, an electric heater, and a relay to realize the isolation of strong and weak currents and communication isolation communication module, and a relay feedback circuit; the power cord of the three-pole leakage protection plug is connected to the power supply line of the electric water heater; the relay is connected between the power cord of the three-pole leakage protection plug and the electric heater for Control the on-off circuit of the electric heater; the single-chip microcomputer is connected with the relay signal through the drive circuit to control the pull-in or disconnection of the relay; the isolated communication module is connected with the single-chip microcomputer and the three-pole leakage protection plug power line signal, and The three poles of the power line of the three-pole leakage protection plug are controlled to be disconnected or closed according to the instructions sent by the single-chip computer; the relay feedback circuit is connected between the relay and the single-chip computer.

As an improvement, the relay includes a first relay and a second relay, the first relay is connected between the L pole of the power cord of the three-pole leakage protection plug and the positive pole of the electric heater, and the second relay is connected between the three-pole Between the N pole of the leakage protection plug power line and the negative pole of the electric heater, the single-chip microcomputer is connected to the first relay and the second relay signal through the drive circuit, and is used to control the pull-in or disconnection of the first relay and the second relay, The relay feedback circuit is connected with the first relay and the second relay at the same time.

As an improvement, the isolation communication module is a photocoupler capable of isolation and communication of strong and weak electricity.

As an improvement, the isolated communication module is connected with the single-chip microcomputer and the power cord of the three-pole leakage protection plug through a communication line; or, the communication between the isolated communication module and the single-chip microcomputer and the power cord of the three-pole leakage protection plug is through a wireless communication module .

As an improvement, the isolation communication module is arranged on the body of the electric water heater or on the power line of the three-pole leakage protection plug or integrated on the single-chip microcomputer.

As an improvement, the wireless communication module is an RF radio frequency module, a Modbus communication module, a ZigBee communication module, a Bluetooth communication module or a WiFi communication module.

As an improvement, a display screen and a main control board are connected to the single-chip microcomputer, and buttons for human-computer interaction and an infrared remote control signal receiving head are arranged on the main control board.

As an improvement, when the relay is working normally, the single-chip microcomputer controls the relay to pull in through the driving circuit. After the relay is pulled in, the relay feedback circuit sends a feedback signal to the single-chip microcomputer, and the electric water heater control system works normally; when the single-chip microcomputer turns off the relay through the driving circuit, the relay After the disconnection, the feedback signal of the relay disappears, and the single-chip microcomputer determines that the system is in a normal working state after detection; when the relay contacts are sticky, the single-chip microcomputer controls the relay to disconnect through the drive circuit, and the relay cannot be disconnected due to the sticky contacts, and the relay feedback The circuit continues to send feedback signals to the single-chip microcomputer. After the single-chip microcomputer detects it, it determines that the electric water heater system is in an abnormal working state. Through the communication between the isolated communication module and the power line of the three-pole leakage protection plug, the power line of the three-pole leakage protection plug is tripped, and the power supply of the water heater is three-pole. disconnect.

The beneficial effects of the utility model are:

By setting the relay feedback circuit and the leakage protection plug that is automatically cut off; when the relay fails to be disconnected normally during use, the feedback circuit transmits a signal to the single-chip microcomputer. After the single-chip microcomputer detects the signal, it sends a power-off command to the leakage protection. Tripping, cutting off the power supply of the electric water heater, effectively preventing accidents such as electric shock and fire, and improving the safety performance of users when using it.

Description of drawings

Fig. 1 is a schematic structural diagram of the electric water heater control system provided by the utility model.

Explanation of reference signs:

1: Three-pole leakage protection plug power cord, 2: Single-chip microcomputer, 3: Electric heater, 4: Relay, 5: Isolated communication module, 6: Relay feedback circuit, 7: Power supply line, 8: Display screen and main control board.

4-1: first relay, 4-2: second relay.

detailed description

In order to facilitate those skilled in the art to better understand the essence of the utility model, the specific implementation of the utility model will be described in detail below in conjunction with the accompanying drawings.

As shown in Figure 1, an electric water heater control system with a relay fault feedback function includes: a three-pole leakage protection plug power cord 1 that can be automatically disconnected and reset, a single-chip microcomputer 2, an electric heater 3, and a relay 4 for An isolation communication module 5 and a relay feedback circuit 6 for realizing strong and weak current isolation and communication.

Wherein, the power line 1 of the three-pole leakage protection plug is connected to the power supply line 7 of the electric water heater. The relay 4 is connected between the three-pole leakage protection plug power line 1 and the electric heater 3, and is used to control the electric heater 3 on and off. The single-chip microcomputer 2 is connected to the relay 4 through a drive circuit for signal connection, and is used to control the pull-in or disconnection of the relay 4 . The isolated communication module 5 is connected to the signal of the single-chip microcomputer 2 and the three-pole leakage protection plug power line 1, and controls the three poles of the three-pole leakage protection plug power line 1 to be disconnected or closed according to the instructions issued by the single-chip microcomputer 2; the relay feedback circuit 6 is connected between the relay 4 and the single-chip microcomputer 2, and is used to feedback the working state of the relay 4.

During actual work, the single-chip microcomputer 2 controls the relay 4 to pull in through the driving circuit. After the relay 4 is pulled in, the relay feedback circuit 6 sends a feedback signal to the single-chip microcomputer 2, and the electric water heater control system works normally. When the single-chip microcomputer 2 disconnects the relay 4 through the driving circuit, the relay feedback signal disappears after the relay 4 is disconnected, and after the single-chip microcomputer 2 detects it, it is judged that the system is in a normal working state; The control relay 4 is disconnected, and the relay 4 cannot be disconnected due to sticky contacts. The relay feedback circuit 6 continues to send a feedback signal to the single-chip microcomputer 2. After the single-chip microcomputer 2 detects it, it determines that the electric water heater system is in an abnormal working state. The power line 1 of the three-pole leakage protection plug communicates with each other, so that the power line 1 of the three-pole leakage protection plug trips, and the three poles of the water heater power supply are disconnected, so as to ensure the safe use of the water heater.

In this embodiment, preferably the relay 4 includes a first relay 4-1 and a second relay 4-2, and the first relay 4-1 is connected between the L pole of the three-pole leakage protection plug power line and the positive pole of the electric heater , the second relay 4-2 is connected between the N pole of the power cord of the three-pole leakage protection plug and the negative pole of the electric heater, and the single-chip microcomputer 2 communicates with the first relay 4-1 and the second relay 4-2 through the driving circuit The signal connection is used to control the pull-in or disconnection of the first relay 4-1 and the second relay 4-2, and the relay feedback circuit 6 is connected to the first relay 4-1 and the second relay 4-2 at the same time. Here, the advantage of combining two relays is to effectively improve the safety and the service life of the electric hot water.

The isolation communication module 5 is an optocoupler capable of isolation and communication between strong and weak currents. By triggering the isolation communication module 5 to send a power-off signal or a closing signal, the leakage protection plug power cord 1 is disconnected or closed, and the trigger signal of the isolation communication module 5 can be sent by the single-chip microcomputer. device, body button or remote control terminal.

In order to avoid complicated connection, the isolated communication module 5 is set on the body of the electric water heater. The isolated communication module 5 communicates wirelessly with the single-chip microcomputer 2 and the power cord 1 of the three-pole leakage protection plug through a WiFi module. In other embodiments, the isolated communication module is set on the power line of the three-pole leakage protection plug or integrated on the single-chip microcomputer; the communication line, Communication with other wireless communication modules such as a Bluetooth module, a Modbus module, and a ZigBee module is not limited to this embodiment.

Further, a display screen and a main control board 8 are connected to the single-chip microcomputer 2, and buttons for human-computer interaction and an infrared remote control signal receiving head are arranged on the main control board, so as to realize manual control of the electric water heater.

The above specific embodiments have described the essence of the utility model in detail, but the protection scope of the utility model cannot be limited by this. Obviously, under the enlightenment of the essence of the utility model, those skilled in the art can also make many improvements and modifications. It should be noted that these improvements and modifications all fall within the protection scope of the claims of the utility model.

Claims (7)

1. An electric water heater control system with a relay fault feedback function, characterized in that it includes: a three-pole leakage protection plug power cord that can be automatically disconnected and reset, a single-chip microcomputer, an electric heater, and a relay to realize strong and weak current Isolated communication module for isolation and communication, and relay feedback circuit; The power cord of the three-pole leakage protection plug is connected to the power supply line of the electric water heater; The relay is connected between the power line of the three-pole leakage protection plug and the electric heater, and is used to control the circuit on-off of the electric heater; The single-chip microcomputer is connected with the relay signal through the driving circuit, and is used to control the pull-in or disconnection of the relay; The isolated communication module is connected with the single-chip microcomputer and the three-pole leakage protection plug power line signal, and controls the three poles of the three-pole leakage protection plug power line to be disconnected or closed according to the instructions sent by the single-chip computer; The relay feedback circuit is connected between the relay and the single-chip microcomputer. 2. A control system for an electric water heater according to claim 1, wherein the relay comprises a first relay and a second relay, and the first relay is connected between the L pole and the power cord of the three-pole leakage protection plug. Between the positive poles of the electric heater, the second relay is connected between the N pole of the power cord of the three-pole leakage protection plug and the negative pole of the electric heater, and the single-chip microcomputer is connected with the first relay and the second relay signal through the driving circuit. To control the pull-in or disconnection of the first relay and the second relay, the relay feedback circuit is connected with the first relay and the second relay at the same time. 3 . The electric water heater control system according to claim 1 , wherein the isolation communication module is a photocoupler capable of isolation and communication of strong and weak currents. 4 . 4. A control system for an electric water heater according to claim 1, wherein the isolated communication module is connected to the single-chip microcomputer and the power cord of the three-pole leakage protection plug through a communication line; Or, the isolated communication module communicates with the single-chip microcomputer and the power cord of the three-pole leakage protection plug through the wireless communication module. 5. A control system for an electric water heater according to claim 1, wherein the isolation communication module is set on the body of the electric water heater or on the power line of the three-pole leakage protection plug or integrated on a single-chip microcomputer. 6 . The electric water heater control system according to claim 4 , wherein the wireless communication module is an RF radio frequency module, a Modbus communication module, a ZigBee communication module, a Bluetooth communication module or a WiFi communication module. 7. A control system for an electric water heater according to claim 1, characterized in that a display screen and a main control board are connected to the single-chip microcomputer, and buttons for human-computer interaction and infrared remote control signal reception are arranged on the main control board. head.