JP7520313B2 - Nutrient solution supply control system - Google Patents

Description

The present invention relates to a nutrient solution supply control system, and in particular to a nutrient solution supply control system that can use one nutrient solution supply device to control nutrient solution supply to a minimum of one area and a maximum of 12 areas, and that can be linked to an effluent reuse controller that can adjust four types of effluent when effluent discharged from a greenhouse is supplied together with raw water through a three-way valve in a circulating hydroponic cultivation system.

Irrigation refers to a method of plant cultivation in which plants are planted in a medium by various methods, such as by planting or sowing, without using land, and then a nutrient solution containing the essential elements required for plant growth in a specified composition ratio is supplied to the plant for its growth.

Plant cultivation using nutrient solution irrigation differs from the method of planting plants in land and allows the environment of the soil in which the plants are planted to be precisely and uniformly regulated, and is therefore actively used for mass plant production.

In addition, the method of cultivating plants using nutrient solution irrigation is currently widely used, because it allows the creation of a plant cultivation area even in places where there is not enough land to secure or where plant cultivation is difficult due to soil contamination.

In this regard, a prior art document showing a conventional technology in which the nutrient solution used for irrigation for plant cultivation is sterilized after being drained, and the nutrient solution is automatically reused along a circulation path established on a control system, is the "Nutrient Solution Circulation Irrigation Control System" in Patent Document 1 (July 18, 2016) (hereinafter referred to as the "conventional technology").

Conventional technologies, including those related to devices or systems for controlling nutrient solution irrigation, only automatically perform nutrient solution irrigation that is repeated along a nutrient solution circulation path from the bulk supply of nutrient solution to the culture medium, the discharge of wastewater from the culture medium, and the recovery of the discharged wastewater, i.e., plant cultivation, but do not suggest any technology for linking multiple greenhouses to which the nutrient solution is supplied to the surrounding environment and for finely controlling the nutrient solution.

Korean Patent Publication No. 10-2016-0085437

The present invention has been made to solve the above problems, and aims to provide a nutrient solution supply control system that can precisely control multiple greenhouses in conjunction with the surrounding environment.

In order to solve the above problem, according to one aspect of the present invention, a nutrient solution supply system for supplying nutrient solution to a plurality of greenhouses is provided, the system including a greenhouse group consisting of a plurality of greenhouses (each of the plurality of greenhouses is supplied with a sensor group for environmental measurement), a nutrient solution supply control device configured to control at least one nutrient solution supply device connected to the greenhouse group via a network, and a user terminal connected to the nutrient solution supply control device via the network, the nutrient solution supply control device configured to collect environmental data from the sensor group installed in each greenhouse in the greenhouse group, and to drive the nutrient solution supply device to supply nutrient solution based on the collected sensor data.

In the above-mentioned embodiment, the sensors installed in the greenhouse include a solar radiation sensor, a soil moisture content measurement sensor, an internal temperature sensor, and an internal humidity sensor.

In addition, in the above-mentioned aspect, the pipeline of the nutrient solution supplying device is further provided with sensors for measuring the EC and pH within the pipeline.

In the above-mentioned aspect, the nutrient solution supply control device provides a user interface screen, the user interface screen includes a nutrient solution control main screen, the main screen includes area information, and the area information is configured to display a set supply amount by area, a remaining supply amount, and a cumulative supply amount, and the set supply amount is displayed as the irrigation amount per area, the irrigation amount set for the area, and the final irrigation set value to which irrigation amount adjustment has been applied, the remaining amount for the irrigation area and the current irrigation amount remaining from the irrigation amount set for the area are displayed as the residual supply amount, and the total daily irrigation amount for the irrigation area is displayed as the cumulative amount. In addition, the EC setting of the standard irrigation amount and the irrigation amount set according to the solar radiation proportion and solar radiation accumulation speed are automatically adjusted for each period, and this automatic precision nutrient solution supply system automatically supplies all of these irrigations according to the schedule.

In the above-mentioned aspect, the nutrient solution supplying device is provided with an LCD display used to provide a user screen, a raw water supply pump used to supply water from the raw water tank to a mixing tank in the nutrient solution supplying device, and a nutrient solution supply pump used to supply nutrient solution from the nutrient solution storage tank to the mixing tank in the nutrient solution supplying device.

The present invention provides a nutrient solution supply control system that can precisely control multiple greenhouses in conjunction with the surrounding environment.

1 is a block diagram showing the overall configuration of a nutrient solution supply control system according to an embodiment of the present invention. 2A and 2B are diagrams showing an example of a nutrient solution supply control system according to an embodiment of the present invention, in which FIG. 2(a) is a diagram showing an example of a sensor group and a driving device in which a nutrient solution supply control system and a composite environmental control system according to an embodiment of the present invention are arranged in each greenhouse within a multiple greenhouse, and FIG. 2(b) is a diagram showing an example of a sensor group and a driving device in the case where a nutrient solution supply control system according to an embodiment of the present invention is arranged alone in a greenhouse. FIG. 2 is a diagram showing a connection structure of a nutrient solution supply control system linked to a complex environmental control system according to an embodiment of the present invention. 1 is a diagram showing the main configuration of a nutrient solution control device used in a nutrient solution supply control system according to an embodiment of the present invention. FIG. FIG. 2 is a diagram showing a lower connection structure of a nutrient solution control device used in a nutrient solution supply control system according to an embodiment of the present invention. FIG. 2 is a diagram showing piping connections between a nutrient solution storage tank, a raw water tank, and a nutrient solution supplying device in the nutrient solution supply control system according to an embodiment of the present invention. FIG. 13 is a diagram showing an example of the configuration of a nutrient fluid control main screen of the nutrient fluid device, among user interface screens. FIG. 13 is a diagram showing an example of a screen for setting the amount of irrigation water in the nutrient solution device. FIG. 13 is a diagram showing a user screen as an example of time-based irrigation settings for a nutrient solution device. FIG. 13 is a diagram showing a user screen as an example of solar radiation proportional irrigation settings. This is a user screen as an example of a solar radiation proportional irrigation setting, showing a user screen in which the irrigation amount is set to time (minutes:seconds) 3 minutes 0 seconds, area water amount 500 L, and dripper (cc) 100 cc. FIG. 13 is a diagram showing an example of a screen configuration for adjusting the amount of irrigation water and the EC value according to the cumulative rate of solar radiation. FIG. 13 is a diagram showing an example of a screen configuration for general settings of the nutrient solution supplying device. FIG. 13 is a diagram for explaining the setting of an EC calibration range to which an EC fine velocity is applied. FIG. 13 is a diagram showing an example of a screen configuration for setting a schedule for a nutrient solution device. FIG. 11 is a diagram illustrating an example of schedule setting. FIG. 13 is a diagram showing a screen as an example of text output of the nutrient solution device. FIG. 13 is a diagram showing a screen as an example of a graph output of the nutrient solution device.

The advantages, features and methods of achieving the present invention will become clearer with reference to the following detailed embodiments in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below and can be realized in various forms.

These embodiments are provided herein to allow those skilled in the art to fully understand the scope of the invention so that the disclosure of the invention is complete. The present invention is defined only by the claims. Therefore, in some embodiments, well-known components, well-known operations, and well-known techniques are not specifically described to avoid obscuring the invention.

Throughout the specification, the same reference numerals refer to the same components. Furthermore, the terms used in this specification are used to describe the embodiments and do not limit the present invention. In this specification, the singular expression includes the plural expression unless otherwise specified. Furthermore, components and operations referred to as "including" do not exclude the presence or addition of one or more other components and operations.

Unless otherwise specified, all terms (including technical and scientific terms) used in this specification are used in the sense commonly understood by those having ordinary knowledge in the technical field to which the present invention belongs. Furthermore, terms defined in commonly used dictionaries should not be interpreted ideally or excessively unless otherwise specified.

Below, an embodiment of the present invention will be described with reference to the attached drawings. FIG. 1 is a block diagram showing the overall configuration of a nutrient solution supply control system 1 including a nutrient solution supply control device 20 according to an embodiment of the present invention. As shown in FIG. 1, the nutrient solution supply control system 1 includes a greenhouse group 10 consisting of a plurality of greenhouses 10a to 10n, a nutrient solution supply control device 20 connected to the greenhouse group or included in the facilities of the greenhouse group, a nutrient solution management server 30 connected to the nutrient solution supply control device 20 via a network, and a user terminal 40 connected to the nutrient solution management server 30 via a network.

The nutrient solution supply control device 20 collects environmental data (culture medium moisture content, Ph, EC, internal temperature, internal humidity, _CO2 , external temperature, wind direction, wind speed, rainfall, solar radiation, etc.) from the sensor groups 100 installed in each greenhouse within the greenhouse group, drives the nutrient solution supply device installed inside the greenhouse based on the collected sensor data, and is equipped to transmit the collected sensor data to the nutrient solution management server 30 so that the greenhouse can be monitored by the user terminal 40. The nutrient solution supply control device 20 is also configured to be able to receive user commands via the nutrient solution management server 30.

2 is a diagram showing an example of a sensor group 100 and a nutrient solution supplying device 20 (including other driving devices 150) arranged in each greenhouse in a multiple greenhouse, and when the composite environmental control system and the nutrient solution supplying system are linked as shown in FIG. 2(a), the greenhouse internal sensor 110 for measuring the internal environment of each greenhouse and the external weather sensor 120 for measuring the external environment of the greenhouse are included. The greenhouse internal sensor 110 is preferably, but not limited to, a temperature sensor 111, a humidity sensor 112, and a _CO2 sensor as sensors installed in the above-ground part of the greenhouse, and preferably includes a water content sensor 114, an EC and Ph sensor 115 installed in the root zone of the greenhouse.

It will be apparent to those skilled in the art that the greenhouse weather sensors 120 for measuring the external environment of the greenhouse include, but are not limited to, an external temperature measurement sensor 121, a wind direction and speed sensor 112, and a solar radiation and rainfall measurement sensor 123, and may include other additional sensors depending on the region, geographical characteristics, climate, etc. in which the greenhouse is located.

2, a plurality of other driving devices for adjusting the environment inside the greenhouse are provided inside or outside the greenhouse. These driving devices are provided to adjust or supply the temperature, humidity, _CO2 concentration, light amount, culture medium state, nutrient solution, etc. inside the greenhouse, and include, but are not limited to, a window driving device 151 including a skylight and a side window, a multi-layer heat-retaining curtain driving device 152, a screen and nonwoven fabric driving device 154, a heating and cooling device 154, a supplementary light or LED driving device 155, a _CO2 generating device 156, a flow fan or exhaust fan driving device 157, a sprinkler driving device 158, a fumigation device 159, a nutrient solution supplying device 160, and a wastewater recycling device 162, and other driving devices may be further provided according to other driving elements installed in the greenhouse.

On the other hand, as shown in FIG. 2(b), when the nutrient solution supply system is installed independently, it includes greenhouse internal sensors 110 for measuring environmental factors for precise nutrient solution supply settings and the internal environment of each greenhouse, and external weather sensors 120 for measuring the external environment of the greenhouse. Sensors installed in the above-ground part of the greenhouse include a temperature sensor 111 and a humidity sensor 112, and sensors installed in the root zone include a moisture content sensor 114, an EC and Ph sensor 115, and an external solar radiation sensor 123.

Figure 2 shows the overall configuration for integrated control of the greenhouse, but in the following description, only the configuration related to nutrient solution control will be specifically described. Figure 3 is an explanatory diagram of the communication environment of the nutrient solution supply control system as described above. As shown in Figure 3, in the nutrient solution supply control system, the web mobile terminal 41, the operation PC 43, and the management server 30 communicate with the nutrient solution supply device, specifically the nutrient solution supply control device that controls the nutrient solution supply device, by the TCP/IP communication method. TCP/IP consists of IP (Internet Protocol), which is an Internet protocol for packet communication, and TCP (Transmission Control Protocol), which is a communication protocol. IP does not guarantee the success or failure of packet transmission, and the order in which packets are sent and the order in which they are received may differ, but TCP is a protocol that operates at a higher level than IP, guarantees the transmission of data, and the data is received in the order in which it was sent. These are configured to enable monitoring and management of the internal environment of the greenhouse from a remote location.

On the other hand, when a composite environmental control device for controlling other driving devices is used together with the nutrient solution supply device, the composite environmental control device can receive TCP/IP packet commands from a web mobile terminal, an operating PC or a management server via TCP/IP, and can display the current measurement status of the sensor group to the user in response to the command, and can also operate to drive the driving devices in the driving device group, but here the nutrient solution supply control device 20 and the composite environmental control device 120 are configured to be connected to each other via RS485 serial communication.

Figure 4 is a diagram showing the external front configuration of the nutrient solution supplying device 20 as described above. As shown in Figure 4, the nutrient solution supplying device 20 is equipped with an LCD display used to provide a user screen, a setting switch used to set the functions (described below) provided by the nutrient solution supplying device 20, a raw water supply pump used to supply water from the raw water tank to a mixing tank in the nutrient solution supplying device, and a nutrient solution supply pump used to supply nutrient solution from the nutrient solution storage tank to the mixing tank in the nutrient solution supplying device, and a venturi pump and a liquid fertilizer solenoid valve are connected to the mixing tank.

The Venturi pump mixes the raw water and nutrient solution, and the nutrient solution supply pump supplies it to each area in the greenhouse according to the EC value set.

The liquid fertilizer solenoid valve is a device (valve) for mixing A, B, and acid (PH) concentrate with raw water in the appropriate ratio.

Figure 5 is a diagram showing the lower configuration of the nutrient solution supplying device 20 as described above. As shown in Figure 5, the lower part of the nutrient solution supplying device 20 is equipped with a pressure control valve, a filtration device, a flow meter, and an EC sensor that are connected to a mixing tank in the nutrient solution supplying device.

The pressure control valve is a valve that maintains the proper pressure so that the internal compressed air is supplied at the same level to supply the concentrated solution from the nutrient solution tank to the mixing tank.

The filtration device functions to remove foreign matter before the mixed nutrient solution concentrates A and B are supplied to the greenhouse.

As shown in the figure, the flow meter functions to measure the flow rate from the mixing tank before supplying it to the greenhouse in order to confirm the irrigation amount set in the automatic nutrient solution supply system.

The EC sensor functions to measure the EC value in the piping that supplies nutrients from the mixing tank to the greenhouse based on the supply setting EC value set in the automatic nutrient solution supply system.

Figure 6 shows the connection relationship between the nutrient solution supply device 20, the nutrient solution storage tank 21, and the raw water tank 22 as described above.

The nutrient solution storage tank 21 is composed of multiple storage tanks, each of which stores, for example, a first nutrient solution containing elements required in relatively large amounts for plant growth, another storage tank stores a second nutrient solution containing elements required in relatively small amounts for plant growth, and another storage tank stores a third nutrient solution for adjusting the acidity of the nutrient solution.

Still other storage tanks store supplementary additives for the nutrient solution, such as functional insecticides that impart specific immune functions to plants or the soil environment through irrigation with the nutrient solution.

The nutrient solution supplying device 20 is configured to mix the nutrient solution (including auxiliary additives, if necessary) in the nutrient solution storage tank 21 with the raw water in the raw water tank 22 in a mixing tank within the nutrient solution supplying device according to greenhouse information measured by a solar radiation sensor, a soil measurement sensor, and a temperature and humidity sensor in the greenhouse, and to supply the mixed nutrient solution to the inside of the greenhouse.

As shown in FIG. 4, the nutrient solution supplying device 20 is composed of a raw water supply pump that draws water from the raw water tank, a nutrient solution supply pump that plays the role of mixing the nutrient solution storage tank and the raw water, and a hand tap pump for supplying raw water other than the nutrient solution. Furthermore, an agitator motor is further connected to the nutrient solution storage tank to prevent the concentrated nutrient solution from solidifying.

The nutrient solution supply control device 20 is basically configured as follows.
The nutrient solution supply control system can be set up separately for a minimum of one zone and a maximum of 12 zones using one nutrient solution supply device.
In recirculating hydroponic cultivation, when the wastewater discharged from the greenhouse is supplied together with raw water through a three-way valve, it can be linked to a wastewater reuse controller that can adjust each of the four types of wastewater.
- The irrigation start time can be set to a fixed time before sunrise (the irrigation start time will automatically change according to the sunrise time, which changes each day).
- By dividing a day into four or more cycles and changing the settings for irrigation based on accumulated solar radiation, minimum standby time, maximum standby time, etc. for each cycle, the balance of moisture and nutrients in the root zone can be optimized.
- You can set the amount of water per irrigation by selecting the amount of water by time (minutes:seconds), the amount of water per area, and the amount of water per dripper.
- Two or more groups can be set up, and different irrigation methods can be selected for each irrigation area.
- When determining the amount of irrigation water for each area, the time and water amount can be set to multiple values, and the amount of irrigation water can be determined by the value that is reached first (sensor malfunction prevention program).
- It has upper and lower limit standards for EC/PH, and if there is a sensor malfunction, the sensor value can be ignored and the nutrient solution can be supplied at an arbitrary proportional control setting value.
- Watering times can be set separately for each watering area.
- The set EC value can be decreased in proportion to the solar radiation value.
- Irrigation and EC settings are automatically changed according to the rate of solar radiation accumulation.
- Data such as the amount of irrigation water supplied, EC value, PH value, number of times, and time can be stored.
- It can be linked to a greenhouse complex environmental control device to share solar radiation sensor values and control them via a PC.
- The nutrient solution tank can be selected based on the cumulative daily solar radiation.

In order to realize the above-mentioned functions, the nutrient solution supply control device 20 according to the present invention is provided with a user interface function, an irrigation amount setting function, a time-based irrigation setting function, a solar radiation proportional irrigation setting function, an irrigation amount and EC adjustment function according to the solar radiation accumulation rate, a general setting function, a schedule function, a text output function, and a graph output function.
1. User interface function: It can monitor the settings of nutrient solution irrigation by area, residual amount, cumulative amount and environmental condition in an integrated manner, and has an emergency irrigation supply and stop function.
2. Irrigation volume setting function: Irrigation volume standards can be set for each irrigation area.
3. Time-based irrigation setting function: You can set the number of irrigation times by time, from a minimum of 1 time to a maximum of 28 times.
4. Solar radiation proportional irrigation setting function: It can be configured into 1 to 3 groups and the irrigation rate can be adjusted in proportion to solar radiation.
5. Irrigation amount and EC adjustment function according to the rate of accumulated solar radiation: The amount of irrigation and EC are automatically adjusted according to the rate of accumulated solar radiation.
6. General setting function: Basic settings for nutrient solution supply such as EC, PH, etc.
7. Schedule function: Divide into sections from a minimum of 1 section to a maximum of 8 sections, and set the water volume and EC target according to the irrigation supply start date and period.
8. Text output function: Provides irrigation information such as the set value and current value of the nutrient solution device and environmental detection values in a table.
9. Graph output function: Provides irrigation information such as the set value and current value of the nutrient solution device and environmental detection values in graph form.

1.1 User Interface Function FIG. 7 is a diagram showing an example of the configuration of a nutrient solution control main screen of the first nutrient solution device, among the user interface screens described above.

A. The area information includes the set supply amount by area, the remaining supply amount, and the accumulated supply amount. Only the areas set in the irrigation amount setting are displayed (FIG. 7 is an example for explaining the use, in which four areas are set).
Set amount: The amount of irrigation water per time for the area. The irrigation amount set for the area and the final irrigation set value to which irrigation amount adjustment has been applied are displayed.
・Remaining amount: The remaining amount of irrigation in the irrigation area. The amount of irrigation that is currently remaining is displayed based on the irrigation amount set for the area.
- Cumulative amount: The total amount of irrigation water in the irrigated area in one day. The total amount of irrigation water applied in one day.

B. As the nutrient solution device status information, the time, supplied EC and pH, and greenhouse weather information are displayed.
Start: The start time of irrigation with the nutrient solution device on the day. The earliest irrigation time is displayed.
End: The time when watering of the nutrient solution device is completed for that day.
- Set EC: The set EC value (dS/m) of the current irrigation area.
Set pH: The set pH value (pH) of the current watering area.
Current EC: The current EC supply value (dS/m) of the irrigation area.
Current pH: The current supply pH value (pH) of the irrigation zone.
Date: The current date (year/month/day) of the nutrient solution device.
Time: The current time of the nutrient solution device (hours:minutes:seconds).
- Sunrise time: The sunrise time on that day.
- Sunset time: The time of sunset on that day.
Current solar radiation: current solar radiation (W/m ² ).
Accumulated solar radiation: the current accumulated amount of solar radiation (J/cm ² ).
Flow rate pulse: The current flow rate meter pulse. The total flow rate of the nutrient solution device is displayed. The total irrigation amount is the value obtained by multiplying the pulse unit by the flow rate pulse (L) unit.
Example: When the flow pulse is 150 days, if the flow pulse (L) unit is 10 L, the total irrigation volume is 1500 L (*This is a function that is displayed when a flow sensor is installed).
- Moisture content: The current moisture content of the medium (%).
Medium EC: Current medium EC (dS/m).
Culture medium temperature: the current culture medium temperature (℃).
- Indoor temperature: The current temperature inside the greenhouse (℃).
- Indoor Humidity: The current humidity inside the greenhouse (%).
- Water deficit: the current greenhouse water deficit (g/ ^m3 ).
Piping EC: Current EC value (dS/m) in the piping. Measure the EC in the piping, not the nutrient solution device EC.
*The culture medium sensor and temperature/humidity sensor are optional devices.

C. Irrigation radiation information includes group radiation, 30-minute radiation, and total daily radiation.
G1: Accumulated solar radiation (J/cm ² ) after watering of group 1.
G2: Accumulated solar radiation (J/cm ² ) after watering of the two groups.
G3: Accumulated solar radiation (J/cm ² ) after watering of the three groups.
J/30 min: The cumulative solar radiation (J/cm ² ) measured in the most recent 30 minutes.
J/Day: The accumulated solar radiation amount (J/cm ² ) of the previous day.

D. In the case of emergency irrigation, the nutrient solution device can be manually operated to start and stop emergency irrigation.
Emergency irrigation: Starts emergency irrigation in a set area.
Emergency irrigation stop: Stops emergency irrigation in the set area. Emergency irrigation irrigates the set areas once in order. If emergency irrigation is started after emergency irrigation stop, it will start from the first area, not from the area where it was stopped.

1.2 Setting the Amount of Irrigation Fig. 8 is a diagram showing an example of an irrigation amount setting screen of the nutrient solution supplying device as described above. In the irrigation amount setting, it is possible to set the irrigation setting by area, the irrigation amount, and the end time.

A When setting the zones, the amount of water to be irrigated for each zone is set by time (minutes:seconds), zone water volume (L), and cc/dripper (cc), and the EC and pH are also set.
Time (minutes:seconds): Set the watering time in minutes:seconds. The nutrient solution device will water for the set time (minutes:seconds) [input: 0000 minutes and seconds (mmss)].
Area water volume: Enter the amount of water to be irrigated in L. The nutrient solution device will irrigate only the amount of water set using the flow meter [input: 0 L] (*Can be used when a flow meter is set).
cc/Dripper: Set the amount of water per dripper (button) in cc. The nutrient solution device adjusts the operating time according to the amount of water per hour set using the dripper capacity [input: 0 cc].
Set EC: Set the area irrigation EC (dS/m) [Input: 0.0 dS/m].
Set pH: Set the zone irrigation pH (pH) [input: 0.0 pH].

B When setting irrigation groups, irrigation methods are set for each area.
- When set to the radiation proportional group, zone irrigation is controlled using the radiation proportional irrigation method.
- When set to timed irrigation, zone irrigation is controlled by the timed irrigation settings.
- Solar radiation proportional irrigation setting 1 group: Set 1 group to solar radiation proportional irrigation setting.
- Solar radiation proportional irrigation setting 2 groups: Set to solar radiation proportional irrigation setting for group 2.
- Three groups of irrigation settings proportional to solar radiation: Set to three groups of irrigation settings proportional to solar radiation.
- Timed irrigation: Set to timed irrigation settings.
- Not in use: Area irrigation is not used.

C. When setting the irrigation setting for the nutrient solution device, set the dripper, flow meter unit, and end time of irrigation.
Dripper capacity: Set the watering capacity per hour of the dripper used in the greenhouse [input: 0.0 L/hr].
Flow Rate/Pulse: Sets the pulse (single count) units of the installed flow meter [Input: 0L].
End time: Set the end time to stop watering the nutrient solution device.
- After the end time, irrigation will not start and emergency irrigation will not work.
Fixed: Set the watering end time to a fixed time [Input: 0000 hours (hhmm)].
Sunset: Set the watering end time to a relative time before sunset [Input: 0000 hours (hhmm)].
- If the end time is set to both fixed and sunset, the watering end time will be set according to the sunset setting.

9 is a diagram showing a user screen as an example of the time-based irrigation setting of the first nutrient solution device. In the time-based irrigation setting, the number of irrigation times and the irrigation time for each time are set for the area set to time irrigation in the irrigation amount setting.

A. For irrigation time, set the time to start irrigation for each irrigation session.
- With timed irrigation, you can set up to 29 irrigation times per day.
- Click on the time for each watering session to set the watering time [input: 0000 hours (hhmm)].
- You can enter 0 for times you will not be using the device to set it as unused.
- Watering times must be entered in order. If you enter an unused time, watering will not occur even if you enter a time after that.
- If the entered irrigation time is later than the next irrigation time, the next irrigation will not start.

B. In the supply EC calibration setting, the calibration speed and the calibration upper and lower limits are set.
- The EC speed setting sets the operation interval of the liquid fertilizer solenoid valve, and the EC upper and lower limits set the operation time when the liquid fertilizer solenoid valve is operated.
EC Speed: Sets the speed at which the liquid fertilizer solenoid valve is adjusted by the sensor based on the EC set value. The higher this value, the faster the adjustment speed will be [Input: 0%]. The default is 100%.
-EC High Limit: Sets the maximum range that the liquid fertilizer solenoid valve will open [Input: 0%].
-EC Lower Limit: Sets the minimum range that the liquid fertilizer solenoid valve will open [Input: 0%].
- When the EC upper limit is set to 100%, the solenoid valve operates at a maximum of 100% (when the EC lower limit is set to 10%, the solenoid valve operates at a minimum of 10% (when the general setting is the basic setting at the time of installation)).
-When the sensor fails and 50% is input into the EC upper and lower limits, the liquid fertilizer solenoid valve opens and closes for 1.5 seconds each.

C. In the operating conditions, the amount of irrigation to be applied to the time-based irrigation is set.
- The amount of irrigation water used for time-specific irrigation is the amount of irrigation water applied by area in the irrigation amount setting.

For example, as shown in Figure 9 (b), if the irrigation amount setting is set to time (minutes:seconds) 3 minutes 0 seconds, area water amount 500 L, and dripper (cc) 100 cc, the operating conditions for the time-based irrigation setting will be as follows.
- Watering amount when set by time: The nutrient solution device operates for 3 minutes and 0 seconds.
- Irrigation volume when set based on area water volume: The nutrient solution device will operate until the water volume measured by the flow meter reaches 500 L.
- Watering amount when set by dripper (cc): The nutrient solution device will operate until it reaches 100 cc per dripper.

1.4 Radiation Proportional Irrigation Setting In the radiation proportional irrigation setting, radiation proportional irrigation can be set on the main screen as shown in Fig. 9 (a). In the radiation proportional irrigation setting, multiple groups can be set, and each group can be selected in the radiation proportional irrigation setting tab.

Figure 9 (b) shows an example of solar radiation proportional irrigation settings for the first group of the first nutrient solution device.

In the A cycle setting, the irrigation start time, standby time, irrigation solar radiation, and irrigation rate are set. Four irrigation cycles can be set per day.
- Start time: The start time of the watering cycle set as the time after sunrise or a fixed time is displayed.
Time After Sunrise: Sets the watering start time to a relative time after sunrise [Input: 0000 hours (hhmm)].
Fixed Time: Set the watering start time to a fixed time [Input: 0000 hours (hhmm)].
・If you enter both a time after sunrise and a fixed time, the start time will be set according to the time after sunrise.
Minimum wait time: Sets the minimum irrigation interval. The next irrigation will not start within the minimum wait time from the start of the previous irrigation [input: 0000 minutes and seconds (mmss)].
Maximum wait time: Sets the maximum irrigation interval. If irrigation does not start until the maximum wait time, irrigation will start at the maximum wait time [input: 0000 minutes and seconds (mmss)].
For example, if the sunrise time is 5:11, the sunset time is 19:49, irrigation starts two hours after sunrise (7:11), and ends three hours before sunset (16:49), the minimum wait time is 30 minutes, and the maximum wait time is 3 hours, and it is cloudy and irrigation due to solar radiation is not performed, and irrigation is only performed according to the maximum wait time, then irrigation will be supplied a total of three times.
Accumulative radiation: Sets the group radiation to start irrigation. When the group radiation exceeds the cumulative radiation setting, irrigation starts.
*When "No use" is set in "Whether or not to use cumulative solar radiation", solar radiation is not applied to irrigation, and irrigation is performed only according to the standby time [input: 0 J/cm ² ].
*The current group radiation is displayed at the bottom of the main screen.
Irrigation rate: Sets the irrigation rate that can adjust the irrigation amount for each cycle group. The irrigation amount set in the irrigation amount setting is adjusted in the irrigation rate and is displayed as the setting value on the main screen [input: 0%].
- For an irrigation rate of 100%, the same irrigation amount set in the irrigation amount setting in 3.2 is applied. If 50% is entered, the irrigation amount will be adjusted to half the irrigation amount setting, and if 150% is entered, the irrigation amount will be adjusted to 1.5 times the irrigation amount setting.

In group irrigation conditions B, the operating conditions for irrigation volume by group, nitrogen fertilizer reduction, and whether or not to use cumulative solar radiation irrigation rate are set.
- Operating conditions: In the operating conditions, the irrigation amount to be applied to irrigation is set in time, L, and cc. Time (min:sec): The time (min:sec) set in the irrigation amount setting is set as the group irrigation amount. Zone water amount (L): The zone water amount (L) set in the irrigation amount setting is set as the group irrigation amount. Dripper (cc): The cc/dripper (cc) set in the irrigation amount setting is set as the group irrigation amount.

For example, as shown in Figure 11, if the irrigation amount setting is set to time (minutes:seconds) 3 minutes 0 seconds, area water amount 500 L, and dripper (cc) 100 cc, the operating conditions for the solar radiation proportional irrigation setting will be as follows.
- Irrigation amount when set by time: The nutrient solution device operates for 3 minutes and 0 seconds.
- Irrigation volume when set based on area water volume: The nutrient solution device will operate until the water volume measured by the flow meter reaches 500 L.
- Watering amount when set to dripper (cc): The nutrient solution device will operate until it reaches 100 cc per dripper.
- The irrigation amount used in the solar radiation proportional irrigation setting is the area-specific irrigation amount applied in the irrigation amount setting.
Use of reduced nitrogen fertilizer: This setting changes the liquid fertilizer tank according to the cumulative amount of solar radiation on the previous day. If the cumulative amount of solar radiation on the previous day is less than the set value for use of reduced nitrogen fertilizer, the nutrient solution device uses liquid fertilizer A'B' [input: 0 J/cm ² ].
* If you do not use the nitrogen fertilizer reduction function, you must set it to not used (entering 0 sets it to not used).
- Use or not use cumulative solar radiation: Select whether or not to use the cumulative solar radiation function for watering the group.
*Not in use: Watering starts every maximum standby time regardless of solar radiation.
*Use: When the group radiation is greater than the cumulative radiation setting, irrigation begins.
-Whether to use irrigation rate: Select whether to use the irrigation rate function to adjust the group irrigation rate.
*Not used: If set to not used, it will not be used for the solar radiation proportional irrigation group.
*Usage: Water is irrigated by adjusting the irrigation amount entered in the irrigation amount setting according to the irrigation rate.

C. In the supply EC calibration setting, the calibration speed and the calibration upper and lower limits are set.
- The EC speed setting sets the operation interval of the liquid fertilizer solenoid valve, and the EC upper and lower limits set the operation time when the liquid fertilizer solenoid valve is operated.
EC Speed: Sets the speed at which the liquid fertilizer solenoid valve is adjusted by the sensor based on the EC set value. The higher this value, the faster the adjustment speed will be [Input: 0%]. The default is 100%.
-EC High Limit: Sets the maximum range that the liquid fertilizer solenoid valve will open [Input: 0%].
-EC Lower Limit: Sets the minimum range that the liquid fertilizer solenoid valve will open [Input: 0%].
・If the EC upper limit is set to 100%, the solenoid valve operates at a maximum of 100%. If the EC lower limit is set to 10%, the solenoid valve operates at a minimum of 10%.
-When the sensor fails and 50% is input into the EC upper and lower limits, the liquid fertilizer solenoid valve opens and closes for 1.5 seconds each.
- Solar radiation proportional irrigation settings can be set for groups 1 to 3.

1.5 Adjustment of the Amount of Irrigation Water and the EC Value According to the Accumulation Rate of Solar Radiation FIG. 12 is a diagram showing an example of a screen configuration for adjusting the amount of irrigation water and the EC value according to the accumulation rate of solar radiation.
Adjustment of the irrigation amount and EC value according to the rate of accumulated solar radiation is a setting in which a range of accumulated solar radiation is set, and if the 30-minute accumulated solar radiation is greater than the set value, the irrigation amount and the set EC can be adjusted.
- You can set adjustment ranges for multiple groups (e.g., three) of solar radiation proportional irrigation settings.
- Water Deficit Adjust is a water rate adjustment setting that applies to all three groups.

A In adjusting the solar radiation cumulative rate, the solar radiation range, irrigation rate, and set EC adjustment are set for each solar radiation proportional irrigation group.
In adjusting the cumulative rate of solar radiation, the amount of irrigation water and the supplied EC are adjusted according to the 30-minute cumulative amount of solar radiation (J/30 minutes) at the time of irrigation.
Group 1: 1 J/30 min, 1 irrigation amount adjustment, 1 EC value adjustment.
Group 2: J/30 min 2, irrigation amount adjustment 2, EC value adjustment 2.
Group 3: 3 J/30 min, 3 irrigation amount adjustments, 3 EC value adjustments.
J/30min: Set up to 5 30 minute cumulative irradiance ranges. If the group irradiance is higher than the set value, an adjustment value will be applied [Input: 0 J/ ^cm2 ]
- Irrigation amount adjustment: Set the irrigation amount adjustment value according to the range of accumulated solar radiation for 30 minutes [input: 0%]. The default is 100%.
EC value adjustment: Set the EC adjustment value for each 30-minute cumulative solar radiation range [input: 0%]. The default is 100%.
・When solar radiation accumulation rate adjustment is set, the general solar radiation adjustment is not applied.

B. Water Deficit Adjustment Setting is a setting for adjusting the irrigation rate according to the water deficit in the greenhouse.
- Temperature and humidity sensors must be installed to adjust the amount of water needed based on moisture deficiency.
Range 1 to 4: Set the moisture deficiency range [input: 0 g/m ³ ]. Not used by default.
Adjustment 1 to 4: Set the irrigation rate adjustment value according to the water deficit range [input: 0%]. Not generally used.
・Entering 0 will set it as unused.
If you do not want to use deficiency adjustment, enter "Not Used" in all settings.
*If you enter [0], it will be set as unused.
If the 30-minute accumulated solar radiation and water deficit at the time of irrigation are smaller than the set values for range 1, the irrigation amount and EC value adjustment according to the solar radiation accumulation rate and the water deficit adjustment are not applied.

1.6 General Settings Fig. 13 is a diagram showing an example of a screen configuration for general settings of the nutrient solution supplying device. The general settings allow the user to set nutrient solution supplying device settings such as alarms, sensor calibration, and latitude and longitude.

A In the nutrient solution device EC and pH calibration settings, alarm deviation, calibration range, etc. are set.
EC warning deviation: Sets the deviation range between the current EC and the set EC.
When the difference between current EC and set EC becomes greater than the EC alarm deviation, stop the supply pump [Input: 0.0 dS/m].
When the current EC becomes greater than the set EC by an EC alarm deviation or more, an EC high concentration alarm is generated.
When the current EC becomes smaller than the set EC by the EC alarm deviation or more, an EC low concentration alarm is generated.
EC Alarm Delay: Sets the alarm delay time for generating an EC alarm.
If the deviation continues after the alarm delay time has elapsed, an alarm will be generated [input: 0000 minutes and seconds (mmss)].
- pH alarm deviation: Sets the deviation range between the current pH and the set pH.
When the difference between the current pH and the set pH becomes greater than the pH alarm deviation, stop the feed pump [input: 0.0 pH].
If the current pH becomes greater than the set pH by the pH alarm deviation or more, a high pH alarm is generated.
If the current pH value falls below the set pH value by more than the pH alarm deviation, a high pH alarm is generated.
pH Alarm Delay: Sets the alarm delay time for generating a pH alarm.
If the deviation continues after the alarm delay time has elapsed, an alarm will be generated [input: 0000 minutes and seconds (mmss)].
Effective solar radiation: Solar radiation below the set value is not measured as cumulative solar radiation [input: 0 W/m ² ].
pH High Limit Open: Sets the maximum range that the pH solenoid valve opens to [input: 0%].
pH Lower Limit Open: Sets the minimum range that the pH solenoid valve opens [input: 0%].
-If the sensor fails and 50% is entered into the upper and lower pH limits, the liquid fertilizer solenoid valve will open and close for 1.5 seconds each.
EC Fine Speed: Sets the EC calibration speed that is applied when the difference between the current EC and the set EC is within the EC calibration range setting (30% is the basic setting, and the higher the setting, the faster the calibration speed) [Input: 0%].
EC calibration range: Set the EC calibration range for applying the EC fine velocity, as shown in FIG.
* If the difference between current EC and set EC is within the EC calibration range, apply EC fine rate [input: 0.0 dS/m].
pH Fine Speed: Sets the pH calibration speed that is applied when the difference between the current pH and the set pH is within the pH calibration range setting (30% is the basic setting, and the higher the speed, the faster the calibration speed) [Input: 0%].
pH Calibration Range: Sets the pH calibration range for which the pH fine rate is applied.
If the difference between the current pH and the set pH is within the pH calibration range, apply the pH fine rate [input: 0.0 pH].
pH Calibration Speed: Sets the speed at which the pH solenoid valve is adjusted by the sensor based on the pH setpoint. The higher this value, the faster the adjustment speed will be [Input: 0%]. The default is 100%.

B. In sensor calibration, the zero span of the EC sensor, pH sensor, and solar radiation sensor is set.
Zero: Enter the zero value for each sensor (if the output is DC 4-20mA).
EC1:210.
EC2:210.
pH: 210.
Solar radiation: 0.
Span: Enter the span value for each sensor (if the output is DC 4-20mA).
EC1: 64 (if the range is 0 to 5) or 124 (if the range is 0 to 10).
EC2: 64 (if the range is 0 to 5) or 124 (if the range is 0 to 10).
pH: 173.
Solar radiation: 1000.

C. In solenoid valve correction, the signal length of the liquid fertilizer solenoid valve is corrected.
Correction: Correct the operating time of the liquid fertilizer solenoid valve [input: 0]. The default is 100.
Entering a value larger than the base value will make it operate longer, and entering a smaller value will make it operate shorter.

D. In the case of solar radiation EC reduction, the set EC is adjusted according to the external solar radiation.
Solar radiation EC reduction: Set the set EC adjustment value due to solar radiation [input: 0.0 dS/m].
Minimum irradiance: Set the minimum irradiance at which irradiance EC reduction begins [input: 0 W/m ² ].
Maximum irradiance: Set the maximum irradiance at which the maximum irradiance EC reduction is applied [input: 0 W/m ² ].
*When irrigation amount and EC value adjustment according to the solar radiation accumulation rate is applied, solar radiation EC reduction is not applied.

E The longitude and latitude settings are applied to the astronomical calculations of the nutrient solution device.

F Set the liquid fertilizer solenoid valve operating period and flow meter signal period.
Liquid fertilizer cycle: Set the liquid fertilizer solenoid valve operation reference time [input: 0]. The default is 300.
When 300 is input, the solenoid valve operates with a reference time of 3 seconds.
The solenoid valve correction times for EC, pH upper and lower limits, etc. are controlled to the times set in the liquid fertilizer cycle setting.
Flow rate signal period: If the flow meter pulse (one count) signal is not transmitted within the set time, a low flow rate alarm is generated and then the nutrient solution device system is stopped [input: 0000 minutes and seconds (mmss)].

1.7 Schedule Setting Function FIG. 15 is a diagram showing an example of a screen relating to schedule setting for the first nutrient solution device.
- The schedule function adjusts the amount of irrigation water and the set EC according to the period.
- When the start date and period are set, the irrigation amount and set EC in the irrigation amount setting in 3.2 and the solar radiation proportional irrigation setting in 3.5 are adjusted proportionally to the water amount/EC target value over the set period from the set start date.
- Section: Displays the section for which the schedule is to be set.
Start Date: Set the start date for starting the schedule section [input: 0000 month/day (MMDD)].
Period: sets the last date for which the water volume/EC target setting adjustment will be applied.

The water volume/EC target adjustment for the section is applied proportionally from the set start date over the set period, and from the set period value onwards, watering will be performed at the water volume/EC target adjusted value [input: 0 days].
Water volume/EC target: Sets the water volume and EC adjustment value.
1. Water/EC Target: Adjust 1 Group Irrigation Settings [Input: 0%].
2. Water/EC Target: Adjust Group 2 irrigation settings [Input: 0%].
3. Water Volume/EC Target: Adjust 3 Group Irrigation Settings [Input: 0%].
- A water volume/EC target input value of 100% indicates that this is the basic setting value set in the irrigation volume setting and solar radiation proportional irrigation, 50% indicates that this is 50% of the setting value, and 120% indicates that this is 120% of the setting value.
- The next interval adjusts the irrigation amount and set EC based on the final irrigation setting of the previous interval.
If you do not use the schedule function, you must enter "not in use" on the start date (enter 0000).

For example, as shown in FIG. 16, if one section starts on November 10th and the period is 10 days, the water volume/EC target adjustment value is adjusted by 1/10 each day, and on November 19th, the irrigation volume and set EC are adjusted to the values entered into the schedule function.

1.8 Text Output Function FIG. 17 is a diagram showing a screen as an example of the text output of the first nutrient solution device among a plurality of nutrient solution devices. The text output provides irrigation information such as the setting values and current values of the nutrient solution device in a table.

A. Set the query start and end times, data query interval, and query items for the query period and interval, and for the query items.
Items: Set amount, remaining amount, accumulated amount, set EC & pH, current EC & pH, culture medium moisture content, culture medium temperature, culture medium EC, piping EC, internal temperature, internal humidity, moisture deficit, group solar radiation, 30 minute solar radiation, total day solar radiation set amount and remaining amount, accumulated amount are displayed as the set value of time (minutes:seconds), area water amount (L), cc/dripper (cc).

B Data is output in chronological order according to the data interval setting.

1.9 Graph Output Function FIG. 18 is a diagram showing a screen as an example of a graph output of the No. 1 solution device among a plurality of nutrient solution devices. The graph output provides irrigation information such as the set value and current value of the nutrient solution device in the form of a graph.

A Set the inquiry start and end dates.

B A graph of the set period and items will be displayed. The vertical axis will change to the item clicked in item selection in C.

In item selection C, the data item to be displayed in the graph is selected.
・Select a query item and click the query button A to output a graph.

D You can check the average, minimum, and maximum values for the selected item during the query period.

As shown in Figures 2 and 3, the wastewater recycling device 160 is equipped to collect and sterilize wastewater from greenhouses for reuse, where the collected wastewater is sterilized in an automatic control step, and the sterilization capacity is adjusted according to the sterilization time and sterilization device output settings. The wastewater recycling device sets wastewater reuse standards using a wastewater monitoring device, and wastewater that is not suitable for reuse is diluted with raw water and discharged. The sterilized wastewater is mixed with raw water when supplied, and the mixing ratio is automatically controlled according to the set concentration.

The waste liquid recycling device is a system that sterilizes and stores waste liquid, and reuses it when it is supplied. The basic operation flow is as follows.
(1) Collection of wastewater → (2) Monitoring → (3) Storage of wastewater → (4) Sand filter → (5) Sterilization device → (6) Storage of sterilized wastewater → (7) Supply of nutrient solution

The drainage collection system is mainly used in a recirculating hydroponic cultivation system, where the drainage is collected, filtered, sterilized, and then stored, and mixed with the culture solution when it is supplied. In the monitoring step, the EC, pH, and drainage volume are measured, and in the step before sterilization, the concentration of ions other than Na ⁺ is monitored as necessary.

The effluent to be reused is stored, filtered through a sand filter, and then sterilized by a sterilizer. The operating time and cycle of the sterilizer are automatically controlled, and the sterilized effluent is stored in a sterilized effluent tank and mixed with raw water when supplying nutrient solution. The reuse rate (dilution rate) of the effluent is automatically controlled based on the set EC, which is measured for the solution mixed with raw water.

The devices described above may be implemented using hardware components, software components, and/or a combination of hardware and software components. For example, the devices and components described in the embodiments may be implemented using one or more general-purpose or special-purpose computers, such as a processor, controller, ALU (arithmetic logic unit), digital signal processor, microcomputer, FPGA (field programmable gate array), PLU (programmable logic unit), microprocessor, or other device that executes and responds to commands. The processing device executes an OS and one or more software applications that run on the OS. The processing device also accesses, stores, manipulates, processes, and generates data in response to the execution of the software. For ease of understanding, the description may be given using one processing device, but a person skilled in the art would understand that the processing device may include multiple processing elements and/or multiple types of processing elements. For example, the processing device may include one or more processors and a controller. Other processing configurations, such as a parallel processor, may also be used.

The software may include a computer program, code, command, or one or more combinations thereof, and may configure a processing device to perform a desired operation, or may instruct the processing device, either individually or collectively. The software and/or data may be embodied in a specific type of machine, component, physical device, virtual device, computer storage medium, or device that can provide commands or data to the processing device or be analyzed by the processing device. The software may be distributed over computer systems connected by a network, and may be stored or executed in a distributed manner. The software and data may be stored on one or more computer-readable recording media.

The method according to the embodiment may be formed into program commands executable by various computer means and recorded on a computer-readable medium. The computer-readable medium may include program commands, data files, data structures, etc., either alone or in combination. The program commands recorded on the medium may be specially designed and configured for the embodiment, or may be known and available to those having ordinary skill in the art. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tapes, optical media such as CD-ROMs and DVDs, magneto-optical media such as floptical disks, and hardware devices specially configured to store and execute program commands, such as ROMs, RAMs, and flash memories. Examples of program commands include machine language codes created by compilers, as well as high-level language codes executed by a computer using an interpreter, etc.

Thus, while the present invention has been described with respect to a limited number of embodiments and drawings, those of ordinary skill in the art will appreciate that various modifications and variations from these descriptions may be made. For example, the techniques described may be performed in a different order than described, the components of the described systems, structures, devices, circuits, etc. may be combined in a different manner than described, and/or other components or equivalents may be substituted or substituted, and still desirable results may be obtained.

Therefore, other embodiments, examples, and equivalents to the claims should be construed as being included in the present invention.

10 Greenhouse group 20 Nutrient solution supplying device 30 Server 40 User terminal 100 Sensor group 150 Driving device group 160 Wastewater recycling device

Claims (4)

A nutrient solution supply system for supplying a nutrient solution to a plurality of greenhouses, comprising:
a greenhouse group consisting of a plurality of greenhouses, each of which is provided with a group of sensors for measuring the environment;
A nutrient solution supply control device configured to control at least one nutrient solution supply device connected to the greenhouse group via a network;
a user terminal connected to the nutrient solution supply control device via a network,
the nutrient solution supply control device is configured to collect environmental data from a sensor group installed in each greenhouse in the greenhouse group, and to drive a nutrient solution supply device to supply nutrient solution based on the collected sensor data;
The greenhouse further includes a wastewater recycling device for collecting, sterilizing, and reusing wastewater from the greenhouse.
The collected wastewater is disinfected in an automatic control step, the disinfected wastewater is mixed with raw water at the time of supply, and the wastewater that is not suitable for reuse is diluted with raw water and discharged.
The nutrient solution supply control device provides a user interface screen, the user interface screen includes a nutrient solution control main screen, the main screen includes zone information, and the zone information is configured to display a set supply amount for each zone, a remaining supply amount, and an accumulated supply amount;
The set supply amount displays the amount of irrigation water for the area at one time, the amount of irrigation water set for the area, and the final irrigation set value to which irrigation amount adjustment has been applied; the remaining supply amount displays the remaining amount for the irrigation area and the current irrigation amount remaining from the irrigation amount set for the area; and the accumulated supply amount displays the total irrigation amount for the irrigation area in one day.
The nutrient solution supply control device is set so that emergency irrigation start and emergency irrigation stop of the nutrient solution device can be manually operated,
Here, the emergency irrigation start refers to starting emergency irrigation in a set area, and the emergency irrigation stop refers to stopping emergency irrigation in a set area,
The emergency irrigation is characterized in that the irrigation is started by irrigating the irrigation-set areas once in sequence, and when emergency irrigation is started again after the emergency irrigation is stopped, the emergency irrigation is started from the first area instead of the area where the emergency irrigation was stopped.
Nutrient solution supply system. The sensors installed in the greenhouse include a solar radiation sensor, a soil moisture content sensor, an internal temperature sensor, and an internal humidity sensor.
The nutrient solution supply system according to claim 1. The nutrient solution supplying device is characterized in that a sensor for measuring EC and pH in the pipe is further provided in the pipe.
The nutrient solution supply system according to claim 2. The nutrient solution supplying device is characterized in that it is provided with an LCD display used to provide a user screen, a raw water supply pump used to supply water from a raw water tank to a mixing tank in the nutrient solution supplying device, and a nutrient solution supply pump used to supply nutrient solution from a nutrient solution storage tank to the mixing tank in the nutrient solution supplying device.
The nutrient solution supply system according to claim 1.