KR100802437B1 - Refrigeration electronic training kit using programmable logic controller - Google Patents

Abstract

A refrigeration electronic training kit using a PLC(Programmable Logic Controller) is provided to form various refrigerators and training kits within a short time by forming a circuit by connecting various refrigeration education devices and the refrigeration electronic training kit through a banana jack. A refrigeration electronic training kit using a PLC(210) has a control panel(200) and executes a test after the training kit is connected with various refrigeration education devices through a banana jack. The control panel is composed of an over current breaker(201) automatically cutting off a circuit in an abnormal state caused due to over current and over load of fan motors of a compressor, a condenser, and an evaporator of the refrigeration education device; an SMPS(Switching Mode Power Supply)(202) converting external AC(Alternating Current) power of 220V into DC(Direct Current) power of 24V; a relay(203) automatically operating and controlling the fan motors of the compressor, the condenser, and the evaporator of the refrigeration education device; a terminal block(204) connected through the banana jack to input and output power for the operation of the control panel and the refrigeration education device; the PLC executing sequence control and numerical calculation functions in order to control the refrigeration education device by a program; and a push button(238) operating and stopping the control panel and the refrigeration education device.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a refrigerator,

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a view showing a configuration of a conventional refrigerator electric test apparatus. Fig.

2 is a view showing a configuration of a refrigeration electric power experiment apparatus using a PLC according to the present invention.

3A is a diagram showing an internal configuration of a PLC applied to the present invention;

3B is a block diagram showing an external configuration of a PLC applied to the present invention.

FIG. 4 is a view showing a temperature, pressure, defrost, automatic defrosting and freezing test apparatus to which the present invention is applied. FIG.

5 is a view showing the refrigerant flow of the temperature, pressure and defrost control automatic refrigeration test apparatus shown in FIG.

FIG. 6A is a sequence control circuit diagram for controlling operation of a temperature, pressure, defrost, and automatic defrosting test apparatus configured as an embodiment using the control panel of FIG.

6B is a control circuit diagram for PLC conversion of the control panel of FIG.

Fig. 6C is a main circuit diagram of an output section to the control panel of Fig. 2; Fig.

Fig. 6D is a view showing the input / output wiring of the PLC to the control panel of Fig.

Fig. 6E is a diagram showing an example of ladder programming of the PLC to the control panel of Fig. 2;

Description of the Related Art [0002]

200: control panel 201: overcurrent breaker

202: SMPS 203: Relay

204: Terminal block 210: PLC

211: power supply unit 212: input unit

213: storage unit 214: CPU

215: output unit 216: communication unit

231: Power lamp 232: Stop lamp

233: Operation lamp 234: Defrost lamp

235: Emergency bell 236: Toggle switch

237: Select switch 238: Push button

The present invention relates to a refrigerator electrical test apparatus using a PLC, and more particularly, to a refrigerator electrical test apparatus using a programmable logic controller (PLC), such as a defrost timer, a timer, a relay timer and an electromagnetic contactor, The present invention relates to a refrigerator electric test apparatus using a PLC which is integrated with a programmable logic controller (PLC) and is configured to control various refrigerator electric test apparatuses by a program.

Generally, a common refrigeration system widely used in the industrial field is realized by a combination of a refrigerating machine, a refrigerator and a sensor for control. In order to construct such a refrigeration system, it is necessary to understand the principle and function of the refrigeration system, and to design and configure it. The principle of automatic control by refrigerator and sensor, control operation and circuit design ability are essential.

However, since most of the refrigeration system and the automatic control system are large and concealed, the principle and function of the refrigeration system and the automatic control experiment and practice are difficult and limited.

That is, as shown in FIG. 1, the conventional refrigerator electric test apparatus is equipped with various kinds of freezing education apparatuses (for example, standard refrigeration experiment apparatus, application refrigeration experiment apparatus, temperature, pressure, defrost automatic control refrigeration experiment apparatus, The control panel 1 is provided with an overcurrent circuit breaker 2, a relay 3a (not shown), and a control circuit for controlling the operation of the freezing education device after connecting the respective components of the refrigeration education device, The electric power source lamp 8 and the stop lamp 9 are connected in parallel to each other by a relay 3b, 3c, a defrost timer 4, a timer 5, a relay timer 6, electromagnetic contactors 7a, 7b, 7c, 7d, The operation lamp 10, the defrost lamp 11, the emergency bell 12, the toggle switch 13, the selection switch 14, the push buttons 15a and 15b and the terminal base 16 are provided have.

Therefore, the conventional refrigerator electric test apparatus has various related elements such as the defrost timer 4, the timer 5, the relay timer 6 and the electromagnetic contactors 7a, 7b, 7c and 7d according to the circuit diagram It is difficult to understand the automatic control and A / S of the refrigeration education device because the actual wiring work is difficult, the space is required for the sequence control, and the processing speed is limited. There is a problem that it is complicated.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and it is an object of the present invention to provide a programmable logic controller (PLC) that can perform functions such as a defrost timer, a timer, a relay timer, Programmable Logic Controller) to control a variety of refrigeration electric experiment devices by a program, and to provide a refrigeration electric experiment device using PLC.

It is a further object of the present invention to provide a refrigerator which can be miniaturized and set up by using a programmable logic controller (PLC) And to provide a refrigerator electric experiment apparatus using PLC which can easily experiment and practice.

In order to accomplish the above object, the present invention provides an apparatus for testing a refrigerator using a PLC, comprising: a control panel (200) for connecting a refrigerator to a banana jack; The control panel (200) includes an overcurrent breaker (201) for automatically shutting down a fan motor of a compressor, a condenser, and an evaporator of a freezing educational device by an overload and an overcurrent; An SMPS 202 for converting an AC 220V power source from the outside into a DC 24V power source; A relay (203) for automatically operating and controlling the fan motor of the compressor, the condenser and the evaporator of the freezing educational device; A terminal block 204 connected to the control panel 200 through a banana jack so as to be connected to a power source for the operation of the freezing education device and for inputting and outputting power; A PLC (210) for performing sequence control and a numerical calculation function so as to perform program control of the freezing education device; And a push button 238 for operating and stopping the control panel 200 and the freezing education device.

Preferably, the PLC 210 includes: a power supply unit 211 for converting external power into a power source usable in the PLC 210; An input unit 212 receiving a state signal of the freezing education apparatus or inputting a control signal through the control panel 200; A storage unit 213 for storing various kinds of information related to experiment data, signal processing, application programs, and experiments for testing the freezing education apparatus through the control panel 200; A CPU 214 for decrypting an input signal from the input unit 212 and various information stored in the storage unit 213 to control the processing contents of various experiments; An output unit 215 for outputting various experimental states executed through the CPU 214 and a communication unit 216 for transmitting various experimental results executed by the CPU 214 to an external computer device do.

More preferably, the control panel 200 includes a power lamp 231 that is turned on when the power is turned on to the control panel 200, a stop lamp 232 that is turned on when the control panel 200 is stopped, An operation lamp 233 that is turned on during operation of the control panel 200, a defrost lamp 234 that is turned on when defrosting the evaporator of the freezing training device, A toggle switch (T / S) 236 for turning on / off the DC power supplied to the control panel 200, and a controller (not shown) for controlling the cooling / And a selection switch 237 for on / off controlling the panel to switch between automatic operation and manual operation.

The PLC 210 further includes a CPU status display LED 221 indicating an operation status of the CPU 214 and an input and output LED 222 for displaying a contact state of the input and output terminals of the terminal block 204, A mode setting key position 224 for setting an operation mode of the PLC 210, and a storage for controlling the contents stored in the storage 213 An auxiliary operation dip switch 225, a connector 226 for connecting to an external computer device, and a mounting hook 229 for fixing the PLC 210 to the control panel 200.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a refrigerator electrical test apparatus using a PLC according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 2 is a diagram illustrating a configuration of a refrigerator electric test apparatus using a PLC according to the present invention, FIG. 3 (a) is a diagram showing an internal configuration of a PLC applied to the present invention, Block diagram.

4 is a view showing a temperature, pressure, and defrost automatic control refrigeration test apparatus which is applied to an embodiment of the present invention, and FIG. 5 is a graph showing the temperature, pressure, Fig.

As shown in FIG. 2, the refrigerator electric experiment apparatus using the PLC according to the present invention is installed on the control panel 200.

The control panel 200 of the refrigerator electric test apparatus includes an overcurrent breaker 201, an SMPS 202, a relay 203, a terminal block 204, a PLC 210, a power lamp 231, a stop lamp 232 The operation lamp 233, the defrost lamp 234, the emergency bell 235, the toggle switch 236, the selection switch 237 and the push button 238. [

Specifically, the overcurrent breaker (NFB) 201 is connected to the fan motor of the compressor 111, the condenser 113, and the evaporator 123 of the temperature, pressure, defrost automatic control refrigeration test apparatus shown in FIGS. 4 and 5, This circuit protects wiring and devices from overcurrent caused by short-circuit faults. It stops operation by automatically shutting off the circuit in case of abnormality of the standard freezing test system. It does not need to be replaced like a fuse during shutdown. So that it can be supplied.

The Switching Mode Power Supply (SMPS) 202 is a device for converting an AC 220 V power source to a DC 24 V power source required for a refrigeration electric experiment apparatus using a PLC according to the present invention.

The relay 203 is a device having a function of opening and closing a contact by an electromagnetic force and automatically operates and controls the motors of the compressor 111, the condenser 113 and the evaporator 123 of the temperature, pressure, .

At this time, the principle of the relay 203 is that when the electric current flows through the electromagnetic coil, the fixed iron core becomes an electromagnet, the movable iron piece is sucked, and the movable contact connected thereto is brought into contact with the fixed contact, and when the electromagnetic force is lost, And is returned to its original state.

The terminal block 204 has a function of connecting a power input and an output connected to each other through a banana jack so that a power source can be connected for operation of the refrigerator electric experiment apparatus and various freezing education apparatuses to operate according to the circuit configuration.

A programmable logic controller (PLC) 210 is a program control device for executing a program of functions such as sequencing, timing, counting, and calculation.

That is, the PLC 210 has the defrost timer 4, the timer 5, the relay timer 6, and the electromagnetic contactors 7a, 7b, and 7c provided in the conventional refrigerator electrical test apparatus as shown in Fig. The input unit 212, the storage unit 22, and the storage unit 24, as shown in FIG. 3A, by adding a numerical calculation function to a basic sequence control function of various related elements such as a power supply unit 211, A CPU 213, a CPU 214, an output unit 215, and a communication unit 216 as an internal configuration.

Specifically, the power supply unit 211 converts a power input from the outside into a DC 24 V power supply usable in the PLC 210.

The input unit 212 detects the state of an external device to be controlled, for example, a standard refrigeration experiment apparatus, controls the operation of an external device through the control panel 200, and receives an experiment related program through an external computer and a notebook computer.

That is, the input unit 212 receives information from the toggle switch 236, the selection switch 237, and the push button 238 provided in the control panel 200 of the refrigeration electric experiment apparatus and information from an external device such as a standard refrigeration experiment apparatus It receives the information and connects the signal to the external device.

The storage unit 213 stores various kinds of information related to experimental data, signal processing, application programs, and experiments.

That is, the storage unit 213 stores user programs input through an external computer and a notebook, and experimental data input during operation of the freezing education apparatus.

The CPU 214 decodes an input signal from the input unit 212 and various information stored in the storage unit 213 to control the contents of various experiments.

The output unit 215 outputs various experimental states executed through the CPU 214 through the power lamp 231, the stop lamp 232, the operation lamp 233, the defrost lamp 234, and the emergency bell 235 Output.

The communication unit 216 transmits the results of experiments performed through the CPU 214 to an external computer and a notebook computer through a communication cable such as TCP / IP or RS-232.

At this time, in addition to the basic units 211 to 216, the PLC 210 may connect an extension module for controlling many external peripherals through a separate communication line through the control of the CPU 214. [

3B, the PLC 210 includes a CPU status display LED 221, an input / output LED 222, a battery mount holder 223, a mode setting key position 224, Position 225, connector 226, extension connector 227, terminal block cover 228, and mounting hook 229 as external configurations.

Specifically, the CPU status display LED 221 is an LED indicating the operation status of the CPU 214 and includes a 'PWR LED 221a', a 'RUN LED 221b' and an 'ERR LED 221c' The PWR LED 221a indicates the state of the power supplied to the control panel 200 and the RUN LED 221b indicates the operation state of whether the basic unit of the PLC 210 is normally operating. 221c are displayed when an error of the CUP 214 is detected.

The input / output LED 222 displays the contact state of the input and output terminals of the terminal block 204, and the battery mounting holder 223 mounts the backup battery.

The mode setting key position 224 is a switch for setting the operation mode of the PLC 210. The mode setting key position 224 is a switch for setting the operation mode of the PLC 210. The mode setting key position 224 is set to 'RUN' for executing a program operation, 'PAU / REM' STOP 'menu.

The storage manipulation dip switch 225 controls the user program and the experimental data stored in the storage 213.

The connector 226 is an RS-232C connector for connecting external peripherals such as a computer and a notebook computer. The expansion connector 227 is a connector for mounting the expansion unit. The terminal block cover 228 is connected to the input / And the mounting hook 229 is a means for fixing the PLC 210 to the control panel 200. [

The power lamps (PL) 231 are lamps which are turned on when power is supplied to the refrigerator electric test apparatus. The stop lamps (RL) 232 are lamps which are turned on when the refrigerator electric test apparatus is stopped. The defrosting lamps WL and 234 are defrosted when the defrosting device 123 of the refrigerating and blowing training apparatus is redirected, the defrosting performance deteriorates due to the decrease of the heat transmission rate. It is a lamp that lights up when.

The emergency bell (BZ) 235 is a device that simultaneously operates both the buzzer and the emergency light when abnormalities occur in the refrigerator electrical test apparatus. The toggle switch (T / S, 236) And the selection switch 237 is a switch for switching the automatic operation and the manual operation by controlling the on / off function of the operation circuit of the standard freezing test apparatus shown in Figs. 4 and 5.

Each of the push buttons PB1 to PB3 and 238 uses the b contact as a stop button when stopping the operation of the peripheral device including the standard freezing test device and uses the a contact as the operation button during operation.

That is, when any one of PB1, PB2, and PB3 included in the push button 238 is pressed, the b contact opens and the a contact closes. When the hand is released, the spring contact automatically returns to the a contact and the b contact are closed.

[0005] On the other hand, air conditioning and refrigeration experiment apparatuses capable of performing a real wiring test using a PLC refrigeration electric experiment apparatus as shown in FIG. 2 include an air conditioning experiment apparatus, a refrigeration experiment apparatus, an application refrigeration experiment apparatus, a refrigerant parallel expansion- , Evaporation pressure parallel control refrigeration experiment device, heat pump cooling / heating experiment device, binary refrigeration experiment device, brine refrigeration experiment device, refrigeration automatic control room wiring experiment device, sequence basic experiment device, liquefied nitrogen cold experiment device and vacuum pump set In the present specification, the temperature, pressure, and defrosting automatic control refrigeration test apparatus as shown in FIGS. 4 and 5 and the refrigeration electric test apparatus using the PLC as shown in FIG. 2 are interconnected by using a banana jack Only the experimental example will be described.

That is, the automatic temperature control device for temperature control, defrosting, and defrosting as shown in FIGS. 4 and 5 includes a control panel 100, a compressor 111, a condenser 113 for a filling nipple 112, a receiver 115, The refrigerant flows through the dryer 118, the level gauge 120, the solenoid valve 119, the expansion valve 121, and the evaporator 123.

Specifically, the compressor 111 absorbs heat from the object to be cooled by the evaporator 123 of the temperature, pressure, and defrost automatic control refrigeration experiment apparatus, sucks and compresses the low temperature low-pressure gas refrigerant evaporated, And the temperature is raised so that the liquid can be easily liquefied in the condenser 113 at room temperature.

In other words, the heat generated by the evaporation of the refrigerant in the low heat source (evaporator 123) is converted into a high temperature and a high pressure and is sent to the high heat source (condenser 113). In addition, the charging nipple 112 is attached to the high-temperature low-pressure pipe on the discharge side of the mechanical compressor and the suction side of the automatic control system for temperature, pressure, defrosting and automatic defrosting by controlling the temperature, pressure and defrosting. It is essential for the use of manifold gauges for charging and refrigerant transport. Before the welding of the filling nipple 112 to the high-temperature low-pressure pipe on the compressor discharge side and the suction side, the inner rubber (airtight holding ring) is disassembled before being attached, cooled and reassembled.

The condenser 113 serves to condense the high-temperature, high-pressure refrigerant gas discharged from the compressor 111 of the temperature, pressure, defrosting automatic control refrigeration test apparatus into the air at room temperature. Temperature and high-pressure gas refrigerant discharged from the compressor (111) to surrounding air and cooling water to release the heat of the gas refrigerant, thereby condensing and liquefying it. To the place where the hot wind comes out, the condenser 113 changes the refrigerant gas from the compressor 111 into the refrigerant liquid as a device in the outdoor unit.

Temperature and high-pressure refrigerant gas discharged from the compressor 111 is heat-exchanged with water or air at room temperature, thereby condensing the refrigerant gas into high-temperature, high-pressure liquid refrigerant. The reason for making it liquid is to use latent heat during state change. In order to take a lot of heat from the evaporator 123, the best performance is obtained when the liquid state changes to the gaseous state, that is, when the latent heat is used. If the outside temperature is too high or the condenser 113 is installed in this place or the ventilation is poor, the effect of the evaporator 123 can not be seen due to the condensation temperature and pressure rise. Therefore, avoiding direct sunlight in a well-ventilated place, and as far as possible the closer the distance to the compressor, the greater the effect of freezing. Special care must be taken to clean the fan regularly and ensure good heat exchange with the outside air. The condenser 113 receives the refrigerant gas discharged from the compressor 111, condenses it, and re-liquefies it. If the cooling function of the condenser 113 is large, that is, if the heat exchange between the cooling water and the refrigerant gas is good, the temperature in the condenser 113 is lowered and the condensation pressure is lowered. The amount of the refrigerant gas discharged from the compressor 111 and the cooling action of the condenser 113 are balanced so that the operation is performed at a constant condensation temperature.

If the water and the substance are present in the refrigerant system of the refrigerating machine, the filter dryer 118 may adversely affect the refrigerating machine. Therefore, in order to predict the effect, the filter dryer 118 is installed in the liquid pipe between the expansion valve 121 and the receiver Remove moisture and this material from the system. The solenoid valve 119 for the main pipe is opened and closed when the power is turned on to control the flow of the refrigerant. In the pump down operation, the temperature switch is connected in series to open and close the main valve solenoid valve 119 according to the closing and opening of the temperature switch contact, so that the pump down operation can be performed.

The sight glass 120 is installed on the side of the condenser 113 in the liquid pipe of the refrigeration education apparatus to check whether the proper amount of refrigerant is filled or not and the state of the refrigerant to be dried. When the proper amount of refrigerant is charged and the condensation state is good, the foam state is lost and the liquid refrigerant passes through a clear liquid refrigerant state. When the bubbles are visible but not moving, and when there is air bubbles only at the inlet side and not visible at the outlet side, or when the bubbles are not continuous and occasionally visible, the proper amount of refrigerant is considered to be charged.

The manual expansion valve 121 adiabatically expands the high-temperature and high-pressure liquid refrigerant with the low-temperature low-pressure liquid refrigerant so as to be easily evaporated in the evaporator 123. Condensation When the liquefied refrigerant is released to a wide area through a narrow space, the refrigerant is released from the pressure and starts to evaporate. In addition, the evaporator 123 adjusts the amount of heat to absorb sufficient heat. Further, the evaporator 123 is a heat exchanger in which the low-temperature and low-pressure liquid refrigerant whose temperature and pressure are different from each other in the expansion valve 121 of the refrigerating device absorbs the latent heat of evaporation and performs a cooling action, Is a device that directly absorbs the latent heat of evaporation from the object to be cooled by means of the low-temperature and low-pressure liquid refrigerant from the evaporator.

Therefore, the jack connection holes formed in the control panel 200 of the refrigerator electric experiment apparatus using the PLC according to the present invention as shown in FIG. 2 and the control panel 100 of the temperature, pressure, defrost auto control refrigeration experiment apparatus shown in FIG. After connecting the jack connection hole formed on the jack through a banana jack, set the operation conditions and conduct the experiment.

FIG. 6A is a circuit diagram of an operation control sequence of the temperature, pressure and defrost control automatic refrigeration experiment apparatus of FIG. 4, FIG. 6B is a control (auxiliary) circuit diagram for PLC conversion, 6D is a view showing an input / output wiring diagram of the PLC 210 for the control panel 200 of the refrigerator electric test apparatus using the PLC shown in FIG. 2, and FIG. And FIG. 6E is a diagram showing an example of ladder programming of the PLC 210 for the control panel 200 of the refrigeration electric experiment apparatus using the PLC shown in FIG.

FIG. 6a-identifying code L1, L2 is a line voltage, NFB shown in Figure 6e is a surge _{protector, MC 1, MC 2, MC} 3 is a contactor, R ₀ is a relay, PB1, PB2 the operation and stop switch, THR is SV is a solenoid valve, DPS is a differential pressure switch, PL is a power lamp, RL is a red lamp, WL is a white lamp, TC1 and TC2 are temperature control switches, T is a 24-hour timer coil, T_a is a timer A contact, T_b is a timer B contact, HT is a heating heater, R_MC1 is a relay for a magnetic contactor 1, R_MC2 is a relay for a magnetic contactor 2, R_MC3 denotes a relay for the electromagnetic contactor 3, and R_SV1 denotes a relay for the solenoid valve 1.

Therefore, Fig. 6A uses the configuration of the control panel 100 shown in Fig. 4, and Fig. 6D shows the temperature, pressure, and defrost automatic control of Figs. 4 and 5 using the configuration of the control panel 200 shown in Fig. It is possible to know the cause of the defrosting device 123 during operation of the refrigeration testing device and its effect on the temperature, pressure, defrosting automatic control refrigeration testing device, understand the operation principle of the thermal defrosting, You can program at the same time as you design. In addition, it is possible to design and wire the heat and defrosting circuit of the temperature, pressure, and defrosting automatic control refrigeration test apparatus according to the given conditions by using the refrigeration electric experiment apparatus using the PLC shown in FIG. 2, Can be controlled.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, Of course.

As described above, according to the refrigerator electrical test apparatus using the PLC according to the present invention, the functions of the defrost timer, the timer, the relay timer, and the electromagnetic contactor included in the control panel of the various refrigerator electrical test apparatuses are controlled by the programmable logic controller ; Promgrammable Logic Controller), it is possible to experiment by controlling various kinds of refrigeration electric test apparatus by a program.

Further, according to the present invention, it is possible to miniaturize and set up a complicated and large-sized refrigerator electrical test apparatus through a programmable logic controller (PLC), thereby realizing experiments, exercises, automatic control circuit design, It is easy to experiment and practice.

Further, according to the present invention, various refrigeration apparatuses and refrigeration electric apparatuses can be easily understood and configured in a short time by constructing a circuit by connecting various refrigeration education apparatuses and refrigeration electric apparatuses using PLCs with banana jacks , And can be corrected immediately when misconfigured.

In addition, the present invention can be suitably utilized as educational equipment in the field of air conditioning and refrigeration technology of the International Functional Olympics and National Functional Games by allowing the construction and operation of various refrigeration apparatuses to be directly tried.

Claims (4)

The present invention relates to a refrigerator electrical test apparatus using a PLC, which is connected to various refrigeration education apparatuses including a control panel (200) and a banana jack, The control panel (200) An overcurrent breaker (201) for automatically shutting off the overload and overcurrent circuit when the fan motor of the compressor, condenser and evaporator of the refrigeration education apparatus is overheated; An SMPS 202 for converting an AC 220V power source from the outside into a DC 24V power source; A relay (203) for automatically operating and controlling the fan motor of the compressor, the condenser and the evaporator of the freezing educational device; A terminal block 204 connected to the control panel 200 through a banana jack so as to be connected to a power source for the operation of the freezing education device and for inputting and outputting power; A PLC (210) for performing sequence control and a numerical calculation function so as to perform program control of the freezing education device; And And a push button (238) for operating and stopping the control panel (200) and the freezing education device. The method according to claim 1, The PLC 210, A power supply unit 211 for converting an external power source into a power source usable in the PLC 210; An input unit 212 receiving a state signal of the freezing education apparatus or inputting a control signal through the control panel 200; A storage unit 213 for storing various kinds of information related to experiment data, signal processing, application programs, and experiments for testing the freezing education apparatus through the control panel 200; A CPU 214 for decrypting an input signal from the input unit 212 and various information stored in the storage unit 213 to control the processing contents of various experiments; An output unit 215 for outputting various experimental states executed through the CPU 214; And And a communication unit (216) for transmitting various experimental results, which are executed through the CPU (214), to an external computer device, as an internal configuration. The method according to claim 1, The control panel (200) A power lamp 231 that is turned on when power is supplied to the control panel 200; a stop lamp 232 that is turned on when the control panel 200 is stopped; A defroster lamp (234) which is turned on when defrosting the evaporator of the freezing education device (233), an emergency bell (234) which simultaneously operates the buzzer and the emergency light when the control panel A toggle switch (T / S) 236 for turning on / off the DC power supplied to the control panel 200; and an on / Further comprising a selection switch (237) for switching the temperature of the refrigerant. 3. The method of claim 2, The PLC 210, An input / output LED 222 for indicating the contact state of the input and output terminals of the terminal block 204, and a battery state indication LED 221 for indicating a state of operation of the CPU 214, A holder 223, a mode setting key position 224 for setting an operation mode of the PLC 210, a storage unit operation dip switch position 225 for controlling the contents stored in the storage unit 213, A connector (226) for connecting to an external computer device, and a mounting hook (229) for fixing the PLC (210) to the control panel (200).

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