JPH07322472A - Power short circuit protective relay for air conditioner - Google Patents

Abstract

PURPOSE:To improve the safety of equipment by stopping the supply of commercial power source to an indoor machine by an overcurrent detection and switch device when the dead short of power has occurred by the erroneous connection of a power line at work execution, etc. CONSTITUTION:A controller 8 digitalizes the voltage difference between the signal lines 7 of an overcurrent detector 4 by means of a transformer means 9, and compares it with the preset overcurrent set value 11.When the result as 11 or more in overcurrent set value by the mistaken connection 16 of the power line 109 by error in work execution, etc., the controller 8 sends a signal of continuation so that it may continue the connection between a CPM terminal 2 and an NC terminal 3, to an overcurrent detection and switch device 1 through a transmission means 12, which stops the supply of commercial power 101 to indoor machines 106a and 106b. Hereby the safety of equipment improves.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply short-circuit protection device for an air conditioner which is separated into a plurality of parts.

[0002]

2. Description of the Related Art In recent years, a separation type air conditioner is required to have safety so as not to be in an unsafe state such as smoke or fire of equipment due to dead short circuit of a power source.

Conventionally, a power supply short-circuit protection device such as a dead short-circuit for a power supply generally has a structure as shown in FIG.

As shown in FIGS. 8 and 9, the commercial power source 101 is
It is connected via a current protection device 103 (current fuse) of the outdoor unit 102 and supplies power to the outdoor control circuit 104 of the outdoor unit 102. Further, the commercial power source 101 is the power line a1.
Reference numeral 05 connects the indoor unit 106a and the indoor control circuit 107 of the indoor unit. The indoor unit 106a and the indoor unit 106b are connected by a power supply line b108, and the power source of the indoor unit 106b connected to the end is connected to the outdoor unit 102 by a power supply line c109. Also,
The current protection device 103 is generally blown using a current fuse in order to stop the power supply to the device when an overcurrent occurs. Further, it has been common to provide a DC power supply device in the outdoor unit and also provide a current protection device 103 between the DC power supply device and the commercial power supply in a device in which the indoor unit is driven by the DC power supply.

In the above structure, if the power supply line c109 is erroneously connected due to construction or the like as shown in FIG. 9, a dead short circuit will occur in the power supply, and an overcurrent 110 will flow and the current protection device 103 will flow.
Is melted and the power supply to the outdoor unit 102 and the indoor units 106a and 106b is stopped. In such an overcurrent protection device, each time the current protection device 103 melts, the current protection device 1
03 must be replaced, and the contractor must always carry maintenance parts to replace the current protection device 103, and correct the incorrectly connected power supply line c109 according to the construction manual. Correction time will occur. In addition, the internal parts of the outdoor unit 102 and the indoor units 106a and 106b may be destroyed.
There was also a big problem in safety such as ignition.

[0006]

In such a conventional power supply short-circuit protection device for overcurrent protection, a dead short circuit of the power supply due to a mistake in connection of the power supply line causes the current protection device to melt and the contractor is constantly It takes time to carry the maintenance parts, replace the current protection device, and properly change the power line. Moreover, in order to confirm whether the current protection device is blown, the panel of the outdoor unit must be removed, and it takes time to confirm the blowout. In addition, safety was a major issue so that the equipment would not be in an unsafe state such as smoke or fire.

The present invention is to solve the above-mentioned problems. When a dead short circuit occurs in the power supply due to an erroneous connection of the power supply line loop during construction or the like, power is supplied to the indoor unit without replacing the current protection device. The first purpose is to protect the outdoor unit and the indoor unit so that the equipment will not be in an unsafe state such as smoking or ignition.

A second object is to easily find the dead short circuit of the power source line when the dead short circuit occurs due to the incorrect loop connection of the power source line at the time of construction.

A third object is to automatically change the polarity of the power supply and supply the power to the equipment when a dead short circuit occurs due to the incorrect connection of the power supply line loop during construction or the like.
Wiring work can be done without considering the polarity of the power line.

A fourth object is to share a current detecting device for protecting a compressor provided in an outdoor unit and a current detecting device for detecting an overcurrent when a power supply line is erroneously connected, thereby reducing costs. To reduce the space.

A fifth object is that in an indoor unit operated by a DC power supply, wiring work can be performed without considering the polarity of the power supply line,
It is to be able to operate the equipment without destroying the parts of the indoor unit.

[0012]

In order to achieve the first object, the power supply short-circuit protection device for an air conditioner according to the present invention has a first means, which is connected to a commercial power supply, and is an overcurrent detection switching device. COM terminal and N of the overcurrent detection switching device
The C terminal receives an overcurrent detection device and the voltage of the overcurrent detection device and supplies power to a plurality of indoor units. Therefore, the control device that switches to the NO terminal of the overcurrent detection switching device and the inside of the control device , Comparing the voltage difference of the overcurrent detection device to a digital signal converted into a digital signal, the digital signal converted by the voltage conversion means, and an overcurrent set value for storing an overcurrent value in case of abnormality in advance A transmission means for transmitting a signal to the overcurrent detection switching device from the comparison calculation determination means and the comparison calculation result is provided, and the output of the overcurrent detection device and the NO terminal of the overcurrent detection switching device are connected,
The outdoor unit connected to the outdoor unit terminal block and the outdoor unit terminal block are connected to the indoor unit terminal block of the indoor unit by the power line a, and
The indoor unit terminal block of the indoor unit and the indoor unit terminal block of the next indoor unit are connected by a power line b, and the indoor unit terminal block of the last indoor unit and the outdoor unit terminal block of the outdoor unit are connected. Power line c
In this configuration, the commercial power supply to the indoor unit is stopped when a dead short circuit occurs due to the incorrect connection of the power supply loop.

In order to achieve the second object, the second
The means for comparing compares the preset overcurrent value at the time of abnormality with the digital signal converted by the voltage converting means by the comparison calculation determining means, and the result of the comparison calculation exceeds the overcurrent value at the time of abnormality. In this case, an abnormal signal transmitting means for outputting an abnormal signal is provided, and the abnormal signal transmitting means is connected to the abnormal display device by the signal line b, and when a dead short circuit occurs due to a wrong connection of the power source, a dead short circuit occurs. Is configured to display the occurrence of.

In order to achieve the third object, the third
The means for comparing compares the preset overcurrent value at the time of abnormality with the digital signal converted by the voltage converting means by the comparison calculation determining means, and the result of the comparison calculation exceeds the overcurrent value at the time of abnormality. In the case of, the phase change signal transmission means for transmitting a signal to the phase change device for changing the phase of the power supply is provided,
By changing the phase of the power supply line c, even if a dead short circuit occurs due to incorrect connection of the power supply loop, the device can operate normally without changing the wiring.

In order to achieve the fourth object, the fourth
In the outdoor unit, a low-voltage DC device that supplies power to a high-voltage DC rectifier connected to a commercial power source, a compressor driving inverter connected to the high-voltage DC rectifier, and a control circuit, An overcurrent detection switching device for selecting whether to detect an overcurrent flowing when a dead short occurs between the current detection device that detects a current between the commercial power supply and the high-voltage DC rectifier or to supply power to an indoor unit; and A rectifying / smoothing circuit for converting the AC voltage from the current detecting device into a DC voltage and the rectifying / smoothing circuit in the control device for controlling the overcurrent switching device and the control device receiving the AC voltage of the current detecting device. A to digitize the DC voltage of the circuit
A signal is sent from the D / A conversion circuit and the A / D conversion circuit to the overcurrent detection switching device based on the comparison operation determination means for comparing the overcurrent setting value that stores the overcurrent value at the time of abnormality in advance and the comparison operation determination result. The transmission means for transmitting is provided, and the detection of the overcurrent of the compressor and the detection of the dead short circuit due to the incorrect connection of the power supply loop are detected by the same current detection device.

Further, in order to achieve the fifth object,
Means for providing an input / output terminal A and an input / output terminal B in an outdoor unit and an indoor unit, in which a DC power supply for supplying a DC power to the indoor unit and an outdoor unit terminal block to which the output of the DC power supply is connected are provided. A polarity detecting device is connected to the indoor unit terminal block and the indoor unit terminal block, and the voltage polarities of the input / output terminal A and the input / output terminal B of the indoor unit are detected inside the polarity detecting device. Two photo couplers, input / output terminal A and input / output terminal B
The four signals of the power switching device for short-circuiting or opening the photo coupler and the photo coupler are received by four photo coupler receiving means inside the power control device, the output states of the four signals are compared by the comparing and determining means, and the comparing and determining means is ,
According to a predetermined condition set in advance, the power source switching transmission means for transmitting a signal for switching the terminals of the power source switching device, the input / output terminal A and the input / output terminal B are
The diode bridges are connected to each other, and the outputs of the diode bridges are connected to each other with the same polarity, connected to the indoor unit control circuit of the indoor unit and the power supply control device, and have different polarities between the indoor units and between the outdoor unit and the indoor unit. Even if a power source is connected, the equipment operates without problems.

[0017]

The present invention has the structure of the above-mentioned first means.
If a dead short circuit occurs in the power supply due to incorrect connection of the power supply line loop during construction, etc., a resistor provided inside the overcurrent detection device can provide a power supply short-circuit protection device that does not cause large current overcurrent to flow in the power supply line. .

Further, according to the structure of the second means, when a dead short circuit of the power source occurs due to a wrong connection of the power source line at the time of construction or the like, the abnormal connection of the power source can be easily confirmed by displaying the abnormality of the power source line. Can notify the change of the power line.

Further, according to the structure of the third means, when a dead short circuit of the power source occurs due to a wrong connection of the power source line loop during construction or the like, one of the two power source lines connected to the outdoor unit is By changing the phase of the power supply line with the phase change device, it is not necessary to rewire the power supply line as in the construction manual, and the power can be supplied to the indoor unit and the equipment can operate normally.

Further, according to the structure of the fourth means, the current detection device provided in the outdoor unit for overcurrent protection of the compressor detects the overcurrent flowing at the time of dead short circuit due to the incorrect connection of the power supply line. Sharing the detection device,
Cost and space can be reduced.

Further, according to the structure of the fifth means, in the indoor unit driven by the DC power source, when the power line is connected to the two sets of input / output terminals of the indoor unit terminal block provided in the indoor unit, two sets of input lines are connected. The power supply control device controls whether or not the output terminals are connected, and the power supplied to the indoor unit control circuit is the reverse voltage applied to the electrical components of the indoor unit by unifying the polarity of the input DC power supply with the diode bridge. Can be connected to the input / output terminals of the power supply line without applying the voltage.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIG.
This will be described with reference to 2. The same parts as those in the conventional example are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in the figure, in the outdoor unit 102, the COM terminal 2 of the overcurrent detection switching device 1 has a commercial power source 101.
It is connected to the. Further, the NC terminal 3 of the overcurrent detection switching device 1 is connected to the overcurrent detection device 4, and one side of the overcurrent detection device 4 has a NO terminal 5 of the overcurrent detection switching device 1 and an outdoor unit terminal of the outdoor unit 102. The platform 6 is connected. The overcurrent detection device 4 has a simple structure with an internal resistance, and the voltage difference detected by the overcurrent detection device 4 is transferred to the voltage conversion means 9 inside the control device 8 via the signal line a7. Is entered. The voltage conversion means 9 includes an operational amplifier and an A
A signal which is composed of a / D converter or the like, has a function of converting the input voltage difference into a digital signal, and is converted into a digital signal of the voltage difference detected by the resistance inside the overcurrent detection device 4,
The comparison calculation determination means 10 is provided with a transmission means 12 that performs a comparison calculation with a preset overcurrent setting value 11 and transmits a signal to the overcurrent detection switching device 1 according to the result. The outdoor unit terminal block 6 of the outdoor unit 102 is connected to the indoor unit terminal block 13a of the indoor unit 106a by a power line a105. In addition, the indoor unit terminal block 13 of the indoor unit 106a
a and the indoor unit terminal block 13b of the indoor unit 106b are connected to the power line b.
Further, the indoor unit terminal block 13b of the indoor unit 106b and the outdoor unit terminal block 6 of the outdoor unit 102 are connected by a power line c109, and the outdoor unit 102 and the indoor unit 106 are connected.
a and 106b are loop-connected. Indoor unit 106
The control circuits 14a and 14b for controlling a and 106b are connected to the indoor unit terminal blocks 13a and 13b and supplied with power.

With the above configuration, the overcurrent detection switching device 1 connects the COM terminal 2 to the NC terminal 3 in order to detect an overcurrent when the power is turned on. When the power supply line is connected as in the construction manual, the current flows from the NC terminal 3 of the overcurrent detection switching device 1 through the resistance of the overcurrent detection device 4 to the control circuits 14a, 14b of the indoor units 106a, 106b.
A current a15 that returns to the commercial power supply 101 through b flows.
For example, the power line c109 is erroneously connected due to a construction mistake, etc. 1
When the current is changed to 6, the current is the NC of the overcurrent detection switching device 1.
A current b17 that returns from the terminal 3 to the commercial power supply 101 through the overcurrent detection device 4 flows. Therefore, a large current b17 flows through the overcurrent detection device 4 as compared to when the power supply line is normally connected, and the voltage difference between the signal lines a7 becomes large. The control device 8 converts the voltage difference between the signal lines a7 of the overcurrent detection device 4 into a digital signal by the voltage conversion means 9, and by the comparison calculation determination means 10,
When a comparison calculation is performed with the preset overcurrent setting value 11, and the result is equal to or more than the overcurrent setting value 11, the control device 8 sends a C to the overcurrent detection switching device 1 via the transmission means 12.
A continuation signal (not shown) is transmitted to continue the connection between the OM terminal 2 and the NC terminal 3. Further, when the voltage of the overcurrent detection device 4 is less than or equal to the overcurrent set value 11, the control device 8
Transmits an indoor unit power supply signal (not shown) to the overcurrent detection switching device 1 via the transmission means 12, and the overcurrent detection switching device 1 receives the signal, and the overcurrent detection switching device 1 receives the COM terminal 2 and the NC terminal 3. The connection is changed from COM connection to COM terminal 2 and NO terminal 5 to supply power to the indoor units 106a and 106b. It should be noted that the overcurrent set value 11 is set to a value such that it is determined that an overcurrent is abnormal when the set value is equal to or more than the set value.

As described above, according to the power supply short-circuit protection device for the air conditioner of the first embodiment of the present invention, there is no need to replace the current protection device (current fuse) due to dead short circuit of the power supply due to incorrect connection during construction. , The safety can be improved.

In this embodiment, the commercial power source is used for explanation, but the same can be considered when a DC power source is provided in the outdoor unit to supply power to the indoor unit. Further, the control device 8 can be easily realized by replacing the comparison calculation determination means 10, the overcurrent set value 11, and the transmission means 12 with a microcomputer.

Next, a second embodiment of the present invention will be described with reference to FIG. The same parts as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in the figure, in the outdoor unit 102, the COM terminal 2 of the overcurrent detection switching device 1 is connected to the commercial power source 101. In addition, N of the overcurrent detection switching device 1
The overcurrent detection device 4 is connected to the C terminal 3, and the NO terminal 5 of the overcurrent detection switching device 1 and the outdoor unit terminal block 6 of the outdoor unit 102 are connected to one side of the overcurrent detection device 4.
The voltage difference detected by the overcurrent detection device 4 is input to the voltage conversion means 9 inside the control device 8 via the signal line a7 and converted into a digital signal. The voltage difference of the overcurrent detection device 4 converted into the digital signal is compared and calculated with the preset overcurrent set value 11 by the comparison calculation determination means 10 inside the control device 8, and the comparison calculation determination means is obtained based on the result. Reference numeral 10 denotes a transmitting unit 12 that transmits a signal to the overcurrent detection switching device 1 and an abnormal signal transmitting unit 1 that transmits an abnormal signal when an abnormality occurs.
8 is connected. Further, the abnormal signal transmitting means 18 is
The abnormality display device 20 is connected via a signal line b19. Further, the outdoor unit terminal block 6 is an indoor unit (not shown).
Connected to the power supply.

With the above-described structure, the overcurrent detection device 4 has a larger current b17 than in the case where the power supply line is normally connected as in the construction manual when a dead short circuit occurs due to a construction error or the like, and a signal The voltage difference between the lines a7 becomes large. The control device 8 converts the voltage difference between the signal lines a7 of the overcurrent detection device 4 into a digital signal by the voltage conversion means 9,
The comparison calculation determination means 10 performs a comparison calculation with a preset overcurrent set value 11, and when the result is equal to or more than the overcurrent set value 11, the control device 8 causes the transmission device 12 to transmit the overcurrent detection switching device 1. For COM terminal 2 and NC terminal 3
A continuation signal (not shown) is transmitted so as to continue the connection, and an abnormality signal (not shown) is transmitted from the abnormality signal transmission means 18 to the abnormality display device 20 via the signal line b19. The abnormality display device 20 receives the abnormality signal and receives the LE signal.
It is possible to display or confirm whether or not the power supply line is dead-shorted by D, LCD, lamp, buzzer, speaker or the like. It should be noted that the overcurrent set value 11 is set to a value such that it is determined that an overcurrent is abnormal when the set value is equal to or more than the set value.

As described above, according to the power supply short-circuit protection device for the air conditioner of the second embodiment of the present invention, the abnormal connection of the power supply can be easily confirmed by displaying the dead short circuit due to the incorrect connection of the power supply such as the construction error. can do.

Next, a third embodiment of the present invention will be described with reference to FIG. The same parts as those in the first and second embodiments are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in the figure, in the outdoor unit 102, the COM terminal 2 of the overcurrent detection switching device 1 has a commercial power source 101.
It is connected to the. An overcurrent detection device 4 is connected to the NC terminal 3 of the overcurrent detection switching device 1, and one side of the overcurrent detection device 4 is connected to the NO terminal of the overcurrent detection switching device 1.
The terminal 5 and the outdoor unit terminal block 6 of the outdoor unit 102 are connected. The voltage difference detected by the overcurrent detection device 4 is the signal line a7.
Is input to the voltage conversion means 9 inside the control device 8 and converted into a digital signal. The voltage difference of the overcurrent detection device 4 converted into the digital signal is calculated by the comparison calculation determination means 10.
A comparison calculation determination unit 10 performs a comparison calculation with a preset overcurrent setting value 11, and the comparison calculation determination unit 10 changes the phase of a transmission unit 12 that transmits a signal to the overcurrent detection switching device 1 and a phase of a power supply. The phase change device 21 is connected to the phase change signal transmission means 23 for transmitting a signal to the device 21 via the signal line c22, and the phase change device 21 has a simple structure including only a relay. The outdoor unit terminal block 6 is connected to an indoor unit (not shown) to supply power.

With the above configuration, the controller 8 is activated when the power is turned on.
Connects the COM terminal 2 and the NC terminal 3 of the overcurrent detection switching device 1 to detect the overcurrent, and further connects the phase change COM terminal 24 and the phase change NC terminal 25 of the phase change device 21. Therefore, the terminal 2 of the outdoor unit terminal block 6
6a and terminal 26c have the same polarity, and terminal 26b and terminal 26d
Are the same pole. The overcurrent detection device 4 has a large current b1 when the power supply line is dead-shorted due to a construction mistake or the like, as compared with the case where a normal power supply line is connected, as in the construction manual.
7 flows, and the voltage difference between the signal lines a7 increases. The control device 8 converts the voltage difference between the signal lines a7 of the overcurrent detection device 4 into a digital signal by the voltage conversion means 9, and the comparison operation determination means 10 performs a comparison operation with the preset overcurrent setting value 11. When the result is the overcurrent set value 11 or more, the control device 8 sends a continuation signal (not shown) to the overcurrent detection switching device 1 via the transmission means 12 so as to continue the connection of the COM terminal 2 and the NC terminal 3. No.) and the control device 8 transmits a phase change signal (not shown) from the phase change signal transmission means 23 to the phase change device 21 via the signal line c22. The phase changing device 21 that has received the phase changing signal receives the phase changing NC terminal 25 and the phase changing COM terminal 24.
The connection is changed from the connection to the phase change NO terminal 27 and the phase change COM terminal 24. Therefore, the terminals 26a and 26d of the outdoor unit terminal block 6 have the same polarity, and the terminals 26b and 2
6c has the same polarity. After that, the control device 8 controls the transmission means 1
A switching signal (not shown) for connecting the COM terminal 2 and the NO terminal 5 to the overcurrent detection switching device 1 via 2
By sending the message, power can be supplied to the indoor unit (not shown). It should be noted that the overcurrent set value 11 is set to a value such that it is determined that an overcurrent is abnormal when the set value is equal to or more than the set value.

As described above, according to the power supply short-circuit protection device for an air conditioner of the third embodiment of the present invention, even if a dead short circuit occurs due to a wrong connection of the power supply during construction, it is necessary to correct the wrong connection. Power can be supplied to the indoor unit.

Next, a fourth embodiment of the present invention will be described with reference to FIG. As shown in the figure, the outdoor unit 10
2, a high-voltage DC rectifier 29 connected to the commercial power source 101 via a current detector 28, and a high-voltage DC rectifier 29 connected to a compressor 30 is an inverter 31 for driving a compressor and a compressor driving Is connected to a low-voltage DC device 33 that supplies power to the inverter 31 and the control circuit 32.
When the power is turned on, the commercial power supply 101 is connected to the COM terminal 2 of the overcurrent detection switching device 1, and the COM terminal 2 is connected to the NC terminal 2.
Connected to terminal 3. Further, the NC terminal 3 of the overcurrent detection switching device 1 is connected to the current limiting resistor 34 via the current detection device 28, and one side of the resistor 34 is connected to the NO terminal 5 of the overcurrent detection switching device 1 and the outdoor unit terminal block. 6 is connected. The current detection device 28 detects overcurrent for protection of the compressor 30 and two types of detection for detecting an overcurrent due to incorrect connection of the power supply line when the overcurrent detection switching device 1 connects the COM terminal 2 and the NC terminal 3. use. An AC voltage (not shown) detected by the current detection device 28 is sent to the control device 32, converted into a direct current by the rectification / smoothing circuit 35 in the control device 32, and the direct current voltage is converted into a digital signal by the AD conversion means 36. The set overcurrent setting value 11 is compared by the comparison calculation determination means 10, and the transmission means 12 of the control device 32 is used according to the comparison result.
Sends a signal from the overcurrent detection switching device 1.

With the above configuration, when the power is turned on, the overcurrent detection switching device 1 detects the overcurrent and the COM terminal 2
Is connected to the NC terminal 3. When the power supply line is dead-shorted due to a construction error or the like, a large current flows through the resistor 34 and an AC voltage (not shown) is generated in the current detection device 28 as compared to when the power supply line is normally connected. AC voltage is the signal line d3
It is input to the rectification / smoothing circuit 35 of the control circuit 32 via 7 and is further converted into a digital signal by the AD conversion means 36. The digitized overcurrent value is compared and calculated with the overcurrent set value 11 preset in the control device 32 by the comparison calculation determination means 10. If the overcurrent set value is 11 or more, the overcurrent detection switching device 1 If the current value is maintained, and the overcurrent set value is 11 or less, the transmission means 12 of the control circuit 32 transmits a switching signal (not shown) to the overcurrent detection switching device 1. The overcurrent detection switching device 1 receiving the switching signal is connected to the COM terminal 2 and the NC.
The connection of the terminal 3 is changed to the connection of the COM terminal 2 and the NO terminal 5, and power is supplied to the indoor unit (not shown). The overcurrent set value 11 is the high voltage DC rectifier 2 in which the current flowing through the resistor 34 and the compressor 30 are stopped when the power supply line is dead shorted.
The current to which the current flowing in 9 is added is set as the overcurrent setting value.

As described above, according to the power supply short-circuit protection device for an air conditioner of the fourth embodiment of the present invention, the overcurrent detection for the protection of the compressor 30 and the dead short-circuit overcurrent detection due to the erroneous connection of the power supply loop are the same. It can be detected by the current detection device 28. The current detection device 28 can be easily realized by using a current transformer.

Next, a fifth embodiment of the present invention will be described with reference to FIGS. As shown in the figure, the commercial power supply 101 is an indoor unit 106 that operates from a DC power supply.
A DC power supply device 38 for supplying a DC power supply to a and 106b is provided in the outdoor unit 102, the output of the DC power supply device 38 is connected to the outdoor unit terminal block 6, and the terminals 26a and 26c of the outdoor unit terminal block 6 have the same polarity. Therefore, the terminals 26b and 26d are connected to have the same polarity. The outdoor unit terminal block 6 has a power line a105.
Are connected to the indoor unit terminal block 13a of the indoor unit 106a by means of the indoor unit terminal block 13a of the indoor unit 106a and the indoor unit 10
The indoor unit terminal block 13b of 6b is connected by the power supply line b108, and the indoor unit terminal block 13b of the indoor unit 106b and the outdoor unit 1 are connected.
The outdoor unit terminal block 6 of 02 is connected by the power supply line c109. The indoor unit terminal blocks 13a and 13b have two sets of input / output terminals A39a and 39b and input / output terminals B39c and 39d.
The polarity detection device 40 is connected via the
Inside, there are four photo couplers 41 that detect the voltage polarity.
a, 41b, 41c, 41d are provided, and the output signals of the four photocouplers 41a, 41b, 41c, 41d are
Photocoupler receivers 43a, 4 inside the power supply controller 42
The signals 3b, 43c, and 43d are received, and the comparison / determination means 44 compares the four signals, and a signal for switching the terminal of the power supply switching device 45 is transmitted from the power supply switching transmission means 46 according to a predetermined comparison condition. The two sets of input / output terminals A39a, 39b and input / output terminals B39c, 39d are
The diode bridges 47a and 47b are connected to each other, and the outputs of the diode bridges 47a and 47b are connected to each other with the same polarity to supply power to the indoor unit control circuit 48 and the power supply control device 42 of the indoor unit 106.

With the above configuration, the indoor units 106a, 106
DC voltage is supplied from the DC power supply device 38 to the input / output terminals A39a, 39b of the indoor unit terminal block 6 of FIG.
It is assumed that the + voltage is connected to 39a and the GND is connected to the input / output terminal A39b. A current c49a flows through the photocoupler 41a provided in the polarity detection device 40, and the signal on the output side thereof is received by the photocoupler receiver 43a of the power supply control device 42. Also, no current flows through the photocoupler 41b. The input / output terminals A39a and 39b are connected to the input of the diode bridge 47a, and the diode bridge 47a
Of the output of the power supply line d50a is always + voltage, and the power supply line d50b is
Becomes GND and the indoor unit control circuit 48 and the power supply control device 42
Power to. Comparison determination means 44 of power supply control device 42
When the signal is received by the photocoupler receiver 43a,
It is confirmed whether the signals are received by the other photocoupler receivers 43c and 43d, and the photocoupler receivers 43c and 43d are received.
If there is no signal at d, or the photocoupler receiver 43
When the signal is received only in c, a terminal ON signal (not shown) for shorting the terminal is output to the power source switching device 45 via the power source switching transmitter 46, and the indoor unit terminal block 13 is turned on. Output terminal A39a and input / output terminal B39
c, and the input / output terminal A39b and the input / output terminal B39d
Are connected. The comparison determination means 44 of the power supply control device 42 does not transmit the terminal ON signal to the power supply switching device 45 when the photocoupler receiver 43d receives the signal. When GND is connected to the input / output terminal A39a and + voltage is connected to the input / output terminal A39b, the current c49b is supplied to the photocoupler 41b provided in the polarity detection device 40.
And the signal on the output side is received by the photocoupler receiver 43b of the power supply control device 42. Also, no current flows through the photocoupler 41a. Furthermore, the input / output terminal A3
9a and 39b are connected to the input of the diode bridge 47a, and the output of the diode bridge 47a has the + voltage on the power supply line d50a and the GND on the power supply line d50b as described above.
Next, power is supplied to the indoor unit control circuit 48 and the power supply control device 42. When the signal is received by the photocoupler receiver 43b, the comparison / determination means 44 of the power supply control device 42 confirms whether or not the signal is received by the other photocoupler receivers 43c, 43d, and signals are sent to the photocoupler receivers 43c, 43d. When there is no signal, or when the signal is received only by the photocoupler receiver 43d, a terminal ON signal (not shown) for shorting the terminal is output to the power supply switching device 45 via the power supply switching transmission means 46. The input / output terminal A39a and the input / output terminal B39c of the indoor unit terminal block 13,
Also, the input / output terminal A39b and the input / output terminal B39d are connected. The above description is based on the assumption that the input / output terminals A39a, 39b are powered first than the input / output terminals B39c, 39d of the indoor unit terminal block 13, but the input / output terminals B39c, 39d are powered first. You can think in the same way when you are asked.

As described above, according to the power supply short-circuit protection device for the air conditioner of the fifth embodiment of the present invention, in the indoor unit 106 driven by the DC power source, two sets of the indoor unit terminal block 13 provided in the indoor unit 106 are provided. The wiring of the power supply line can be done without considering the polarity when connecting the power supply line to the input / output terminal.

[0041]

As is apparent from the above embodiments, according to the present invention, it is not necessary to replace the current protection device (fuse) when a dead short circuit of the power source occurs due to an incorrect connection of the power source line during construction or the like. With the overcurrent detection switching device, it is possible to provide a power supply short-circuit protection device for an air conditioner, which has the effect of improving the safety of the device by stopping the supply of commercial power to the indoor unit.

Further, when a dead short circuit of the power source occurs due to an incorrect connection of the power source line during construction or the like, it is possible to easily find the occurrence of the dead short circuit and to inform the installer of the correction of the power source line. A power supply short-circuit protection device for an air conditioner can be provided.

Further, when a dead short circuit of the power source occurs due to an incorrect connection of the power source line during construction or the like, the polarity of the power source line is automatically changed without supplying the power source line, and power is supplied to the indoor unit.
Since it is not necessary to perform wiring work in consideration of the polarity of the power supply line, it is possible to provide a power supply short-circuit protection device for an air conditioner, which has the effect of improving workability.

Further, when a dead short circuit of the power source occurs due to an incorrect connection of the power source line during construction or the like, a current detecting device for detecting an overcurrent of the power source dead short circuit and a current detecting device for detecting an overcurrent of the compressor protection. It is possible to provide a power supply short-circuit protection device for an air conditioner that has the effect of sharing parts and reducing the cost of parts by further sharing the parts.

In the case where the indoor unit is an air conditioner that can be driven by a DC power supply, if the polarity of the power supply line is mistakenly connected during construction, the power supply line does not need to be corrected, and the polarity of the power supply line must be considered. Since there is no need to perform wiring work, workability is improved, and when wiring work is done by mistake with the wrong polarity,
It is possible to provide a power supply short-circuit protection device for an air conditioner, which has an effect of avoiding destruction of parts of the equipment without applying a reverse voltage to the parts of the indoor unit.

[Brief description of drawings]

FIG. 1 is a block diagram of a power supply short-circuit protection device for an air conditioner according to a first embodiment of the present invention.

FIG. 2 is a current path diagram of a power supply short-circuit current of the air conditioner according to the first embodiment of the present invention.

FIG. 3 is a block diagram of a power supply short-circuit protection device for an air conditioner according to a second embodiment of the present invention.

FIG. 4 is a block diagram of a power supply short-circuit protection device for an air conditioner according to a third embodiment of the present invention.

FIG. 5 is a block diagram of a power supply short-circuit protection device for an air conditioner according to a fourth embodiment of the present invention.

FIG. 6 is a block diagram of a power supply short-circuit protection device for an air conditioner according to a fifth embodiment of the present invention.

FIG. 7 is an internal configuration diagram of an indoor unit side of a power supply short-circuit protection device for an air conditioner according to a fifth embodiment of the present invention.

FIG. 8 is a block diagram of a conventional power supply short-circuit protection device for an air conditioner.

FIG. 9 is a current path diagram of a power supply short-circuit current of a conventional air conditioner

[Explanation of symbols]

 1 Overcurrent detection switching device 2 COM terminal 3 NC terminal 4 Overcurrent detection device 5 NO terminal 6 Outdoor unit terminal block 8 Control device 9 Voltage conversion means 10 Comparison calculation determination means 11 Overcurrent set value 12 Transmitting means 13a Indoor unit terminal block 13b Indoor unit terminal block 18 Abnormal signal transmitting means 19 Signal line b 20 Abnormality display device 21 Phase changing device 23 Phase changing signal transmitting means 28 Current detecting device 29 High voltage direct current rectifying device 30 Compressor 31 Inverter 32 Control circuit 33 Low voltage direct current Device 35 Rectifying / Smoothing Circuit 36 AD Converter 38 DC Power Supply Device 39a Input / Output Terminal A 39b Input / Output Terminal A 39c Input / Output Terminal B 39d Input / Output Terminal B 40 Polarity Detector 41a Photocoupler 41b Photocoupler 41c Photocoupler 41d Photocoupler 42 Power Supply Control Device 43a Photocoupler Receiver 43d Photo coupler receiver 43c Photo coupler receiver 43d Photo coupler receiver 45 Power supply switching device 46 Power supply switching transmission means 47a Diode bridge 47b Diode bridge 101 Commercial power supply 102 Outdoor unit 105 Power supply line a 106a Indoor unit 106b Indoor unit 108 Power supply line b 109 Power line c

Claims (5)

[Claims] 1. A COM terminal of an overcurrent detection switching device connected to a commercial power source and an NC of the overcurrent detection switching device.
An overcurrent detection device at the terminal, and a voltage for receiving the voltage of the overcurrent detection device and supplying power to a plurality of indoor units. Therefore, the control device that switches to the NO terminal of the overcurrent detection switching device and the inside of the control device, A comparison that compares the voltage difference of the overcurrent detection device with a digital signal converted into a digital signal, a digital signal converted by the voltage conversion unit, and an overcurrent set value that stores an overcurrent value in the event of an abnormality in advance. Provided with a calculation determining means and a transmitting means for transmitting a signal from the comparison calculation result to the overcurrent detection switching device, connecting the output of the overcurrent detection device and the NO terminal of the overcurrent detection switching device to the outdoor unit terminal block. The connected outdoor unit and the outdoor unit terminal block are connected to the indoor unit terminal block of the indoor unit by the power line a, and a power supply is provided between the indoor unit terminal block of the indoor unit and the indoor unit terminal block of the next indoor unit. Connect at line b Further, when the indoor unit terminal block of the last indoor unit and the outdoor unit terminal block of the outdoor unit are connected by the power supply line c and a dead short circuit occurs due to incorrect connection of the power supply, the power is supplied to the indoor unit. A power supply short-circuit protection device for air conditioners, which features stopping commercial power. 2. The comparison calculation determining means compares the preset overcurrent value at the time of abnormality with the digital signal converted by the voltage converting means, and the result of the comparison calculation indicates the overcurrent value at the time of abnormality. When exceeding, an abnormal signal transmitting means for outputting an abnormal signal is provided, and the abnormal signal transmitting means is connected to the signal line b.
2. The power supply short-circuit protection device for an air conditioner according to claim 1, wherein the power supply short-circuit protection device is connected to the abnormality display device by the above, and when the dead short circuit occurs due to the incorrect connection of the power supply, the occurrence of the dead short circuit is displayed. 3. The comparison calculation determining means compares the preset overcurrent value at the time of abnormality with the digital signal converted by the voltage converting means, and the result of the comparison calculation indicates the overcurrent value at the time of abnormality. If it exceeds, if a phase change signal transmitting means for transmitting a signal to the phase changing device for changing the phase of the power supply is provided and the phase of the power supply line c is changed, a dead short circuit occurs due to a wrong connection of the power supply loop. 2. The power supply short-circuit protection device for an air conditioner according to claim 1, wherein the device can operate normally without changing wiring. 4. The outdoor unit includes a high-voltage DC rectifier connected to a commercial power source, an inverter for driving a compressor connected to the high-voltage DC rectifier, and a low-voltage DC device for supplying power to a control circuit. A current detection device that detects a current between the commercial power supply and the high-voltage DC rectifier, and an overcurrent detection switching device that selects whether to detect an overcurrent that flows when the power supply dead-shorts or supply power to an indoor unit. A rectifying / smoothing circuit for converting an AC voltage from the current detecting device into a DC voltage and a rectifying / smoothing circuit for receiving the AC voltage of the current detecting device and controlling the overcurrent switching device and the inside of the control device. The AD conversion circuit for digitizing the DC voltage of the smoothing circuit, the comparison calculation judgment means for comparing the value of the AD conversion circuit with the overcurrent set value for storing the overcurrent value at the time of abnormality in advance, and A detection means for transmitting a signal from the comparison calculation determination result to the overcurrent detection switching device is provided, and the same current detection device detects overcurrent detection of the compressor and dead short circuit overcurrent detection due to incorrect loop connection of the power supply. Power supply short-circuit protection device for air conditioners. 5. An input / output terminal A and an input / output terminal B are provided in an outdoor unit and an indoor unit provided with a DC power supply device for supplying a DC power supply to the indoor unit and an outdoor unit terminal block to which the output of the DC power supply device is connected. A polarity detection device is connected to the provided indoor unit terminal block and the indoor unit terminal block, and the voltage polarities of the input / output terminal A and the input / output terminal B of the indoor unit are detected inside the polarity detection device. The four signals of the four photo couplers, the power switching device for short-circuiting or opening the input / output terminal A and the input / output terminal B, and the four signals of the photo coupler are four signals inside the power control device.
One photocoupler receiving means receives the signals, and the comparing and judging means compares the output states of the four signals, and the comparing and judging means transmits a signal for switching the terminals of the power supply switching device according to a predetermined condition set in advance. A diode bridge is connected to each of the power source switching transmission means, the input / output terminal A, and the input / output terminal B, and the outputs of the diode bridges are connected to each other with the same polarity, and the indoor unit control circuit of the indoor unit and the power source are connected. A power supply short-circuit protection device for air conditioners that is connected to a control device and operates without problems even if power supplies with different polarities are connected between indoor units and between outdoor units and indoor units.