JPH07158931A - Controller for air-conditioner - Google Patents

Abstract

PURPOSE:To detect failure in operation of a current transformer in an outdoor unit of an air-conditioner. CONSTITUTION:A value of an electric current flowing to a power circuit 2 which supplies power to a compressor 1 prior to and during the operation of the compressor 1 in an outdoor unit of an air-conditioner is detected by a current transformer 4, and the detected current value is inputted into a microcomputer 3. In this structure, the microcomputer 3 compares the inputted current value with a preset value and, when the microcomputer 3 ascertains abnormality of the inputted current value, it judges that the current transformer 4 is defective, and the operation of the compressor 1 is stopped, thereupon the malfunction of the current transformer 4 is displayed by an abnormality displaying LED 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for an air conditioner.

[0002]

2. Description of the Related Art In recent years, in a control device for an air conditioner, a current value flowing in a power circuit is detected by a current transformer during operation of a compressor, and the current value input to a microcomputer is previously stored under operating conditions at that time. When the input value is larger than the input value, the microcomputer mainly controls the power circuit so that the power circuit is not overloaded.

Conventionally, a control device for this type of air conditioner generally has a structure as shown in FIG. The configuration will be described below with reference to FIG.

As shown in the figure, it comprises a control board 105 having a compressor 101, a power circuit 102, and a current transformer 104 for detecting a current value flowing in the power circuit 102 and inputting it to a microcomputer 103. The microcomputer 103 controls the operating state of the compressor 101 based on the current value detected by the transformer 104.

[0005]

In such a conventional air conditioner controller, the current value detected by the current transformer 104 during operation of the compressor 101 is lower than a predetermined value under the operating conditions. The microcomputer 103 controls the operation of the compressor 101 when it is too large. However, the microcomputer 103 causes the compressor 101 to operate due to a failure of the current transformer 104 or disconnection of the wiring.
When the operation is continued without being able to detect the current value of the power circuit even during the operation of the compressor 101,
Even if the current value of the power circuit rises due to the overload, the operation continues as it is, leading to a problem of the air conditioner.

The present invention solves the above problems, and provides an air conditioner control device that detects a current control failure state due to a failure or disconnection of a current transformer during operation of a compressor and stops the compressor to notify an abnormality. That is the first purpose.

The second purpose is to detect the failure of the current transformer early.

[0008]

In order to achieve the above object, the control means for an air conditioner of the present invention has a first means, a power circuit for supplying electric power to a compressor, and a minimum current value during operation of the compressor. And a microcomputer for storing a current value flowing in the power circuit and transmitting the current value to the microcomputer, and an LED for indicating abnormality of the current transformer and peripheral circuits. When the current value input from the current transformer becomes smaller than the stored minimum current value, the compressor is stopped and the abnormality display LED is made to blink.

Further, in order to achieve the second object, the second
The means is that the microcomputer to which the current transformer operation confirmation mode is input executes the current transformer operation confirmation mode before the compressor is running, and the preset current is passed through the current transformer, and the detected current value at that time is detected. Is judged to be correct, and if it is not correct, the compressor is not operated and the LED for displaying an abnormality is made to blink.

[0010]

According to the present invention, by the construction of the above-mentioned first means, when the current value detected by the current transformer during the operation of the compressor and inputted to the microcomputer becomes smaller than the preset value, the microcomputer is operated. Determines that some abnormality has occurred in the peripheral circuit of the current transformer, stops the compressor, and displays the abnormality display LED.
Will be displayed by blinking.

Further, the configuration of the second means makes it possible to detect an abnormality before the current transformer completely fails.

[0012]

【Example】

(Embodiment 1) A first embodiment of the present invention will be described below with reference to FIGS. As shown in the figure, a power circuit 2 for supplying electric power to a compressor 1 provided in an outdoor unit of an air conditioner is provided, and the compressor 1
Of the minimum current value during operation of the microcomputer 3, and the current transformer 4 that detects the value of the current flowing through the power circuit 2 and transmits it to the microcomputer 3.
The control board 6 is provided with an abnormality display LED 5 for notifying an abnormality of the current transformer 4 and peripheral circuits.

With the above configuration, the microcomputer 3
Detects a failure of the peripheral circuit of the current transformer 4 by detecting the value of the current flowing through the power circuit 2 during operation of the compressor 1.

The means for detecting a failure in the peripheral circuit of the current transformer 4 will be described below with reference to the chart shown in FIG. First, the abnormality detecting mode of the current transformer 4 starts in the seventh step, the detection timer UP is started in the eighth step, the microcomputer 3 fetches the current value from the current transformer 4 in the ninth step, and fetches it in the tenth step. If the current value is small, the 11th current value is compared with the previously stored data.
In step 12, the compressor 1 is stopped, and in step 12, the abnormality display LED 5 blinks to display an abnormality and the air conditioner is controlled.

As described above, according to the controller of the air conditioner of the first embodiment of the present invention, the value lower than the current value that should be originally obtained during the operation of the compressor due to the abnormality of the current transformer and its peripheral circuit is micro. When input to the computer, it can be determined that the current transformer or the peripheral circuit is abnormal.

(Embodiment 2) Next, a second embodiment of the present invention will be described with reference to the chart shown in FIG. The same parts as those in the first embodiment are designated by the same reference numerals and detailed description thereof will be omitted. First, before starting the compressor 1, it starts from the operation confirmation mode of the current transformer 4 in the 13th step, a predetermined current is made to flow in the current transformer 4 in the 14th step, and the microcomputer 3 causes the current to flow in the 15th step. The current value is taken in from the transformer 4, the current value taken in the 16th step is compared with the previously stored data, and if they are not the same, the start of the compressor is stopped in the 17th step and the abnormal LED 5 blinks in the 18th step. The error is displayed.

With the above configuration, when a current value different from the current value originally obtained due to the abnormality of the current transformer 4 is input to the microcomputer 3, it is determined that the current transformer 4 is abnormal before the compressor 1 is operated. You can

As described above, according to the controller of the air conditioner of the second embodiment of the present invention, it is possible to detect the failure of the current transformer at an early stage.

[0019]

As is apparent from the above-described embodiments, according to the present invention, a microcomputer in which a minimum current value during compressor operation is stored in advance, and a current value flowing in a power circuit is detected and transmitted to the microcomputer. Since the current transformer and the LED for displaying the abnormality indicating the abnormality of the current transformer and the peripheral circuit are provided, the detected value of the current flowing through the power circuit during the operation of the compressor is a failure of the current transformer and its peripheral circuits. Therefore, even if it becomes an abnormally small value, the microcomputer judges that it is abnormal,
An air conditioner control device that can stop operation and prevent a failure of the air conditioner, and can shorten the time required for repair because it can be recognized as a failure of the current transformer by the display of the LED for displaying an abnormality. Can be provided.

Further, since the abnormality of the current transformer can be detected before the operation of the compressor and the operation of the compressor can be canceled, it is possible to provide the control device of the air conditioner which can prevent the failure of the air conditioner.

[Brief description of drawings]

FIG. 1 is a block diagram showing a control device for an air conditioner according to a first embodiment of the present invention.

FIG. 2 Same chart

FIG. 3 is a chart of the second embodiment.

FIG. 4 is a block diagram showing a control device for a conventional air conditioner.

[Explanation of symbols]

 1 Compressor 2 Power circuit 3 Microcomputer 4 Current transformer 5 LED for error indication

Claims (2)

[Claims] 1. A power circuit for supplying electric power to a compressor, a microcomputer in which a minimum current value during the operation of the compressor is stored in advance, and a current transformer which detects a current value flowing in the power circuit and transmits it to the microcomputer. An abnormality display LED for indicating an abnormality in the current transformer and peripheral circuits, and stops the compressor when the current value input from the current transformer to the microcomputer becomes smaller than the stored minimum current value. Then, the control device of the air conditioner configured to blink the LED for displaying the abnormality. 2. A microcomputer to which a current transformer operation confirmation mode is input executes the current transformer operation confirmation mode before the compressor is operated, and a preset current is supplied to the current transformer, and a current value at that time is supplied. 2. The control device for an air conditioner according to claim 1, wherein it is determined whether or not the detected value is correct, and if the detected value is not correct, the compressor is not operated and the LED for indicating abnormality is blinked.