Climate regulator LB-760A is designed for measurement and regulation of full air conditioning (temperature, humidity, CO2 concentration, aeration) in a mushroom cultivation hall (or a similar cultivation for example in a greenhouse). The regulator is a stationary device, powered from the 220V supply network, built in a form of a panel, which is supposed to be hanged on the wall. The device's design is based on advanced microprocessor technique. The control over the regulator is possible through a remote control. Such solution allows on convenient control over the regulator even in conditions when it is hanged high on the wall or in a place which is not easily accessible. All measurement results are shown on easy to be read LED screens.
Regulator LB-760A is designed to supervise only one cultivation hall. In case when there are more halls it is necessary to use separate regulator for each one of them. The regulators LB-760A installed in each one of the halls connected to a PC computer create a common measurement- control system. Then it is possible to system measure the CO2 concentration level (picture 3), have comfortable control over the regulators form a PC computer, collect measurement results, create data history, view the results in a form of graphs and easily print them. RS485 interface is used to connect the regulators with the computer. The interface assures the use of minimum number of wires between the regulators and a computer as well as wide range of data transmission (few hundred meters).
The regulator LB-760A (picture. 1, 2) can be attached with the following measuring devices:
Picture 1. Devices co-operating with the climate regulator LB-760A: A, B, C and D - probes for ground temperature measurement, E and F - probes for air temperature measurement in the air conditioning centre, G - psychrometer for temperature and air humidity measurement in a hall; exits proportional for regulation: 1 - air throttling valves, 2 - heating valve, 3 - cooling valve, 4 - humidify valve, 5 - ventilator turns; exits: 6 - emergency situation signalling, 7 - switching on the light, 8 - CO2 system measurement valve; transmitter exits for valves type ON/OFF 9 - heating, 10 - cooling, 11 - humidify.
Output regulating signals are results of calculations done during PID regulation procedures basing on set values and actual planned values. For testing and initiating purposes the manual programming of output signals value is possible.
The regulator LB-760A control over the actuators is done through
control (with servos of proportional operation) or in a different way
simulates the proportional regulation basing on the rule ON/OFF with
filling factor, through supply them with voltage 220V / max.1A
The additional possibility is to control the heating device through contact of relay (no voltage output), what allows on control over the modern type of gas furnace or oil furnace.
Picture 2. The arrangement scheme for measurement sensors and actuators for full air conditioning in a cultivation hall HU using regulator LB-760A: A... D - soil temperature measurement probes, E - probe measuring the temperature behind the cooler, F - probe measuring the temperature behind the heater, G - psychrometer, 1..10 - control outputs from LB-760a regulator (output functions: 1 - air, 2 - heating, 3 - cooling, 4 - moistening, 5 - ventilation, 6 - cooling 2 initial, 7 - initial heater, 8 - CO2 measurement, 10 - steam), PU - cultivation, CO - air collection ducts for CO2 concentration measurement system, ZP - air collection valve, PP - air throttle, PC - circulating air, PS - fresh air, CP - fresh air inlet, KM - mixing chamber, CW - initial cooler, CH - main or freon cooler, WW - initial cooling ice water (e.g. from well), WL - main ice water (chiller) or freon, ZW - water valve, SP - servomotor of proportional action, WW - water dephlegmators, SO - reflux water outflow trap OW, WG - hot water, PA - steam, NA - main heater, NW - initial heater, WN - fan o, FA - inverter for regulation of SW fan engine rotations, DW - moistening water inflow, RW - water sprayers, RN - ventilating arm, DN - ventilating nozzles, ZZ - return valve for air WP taken away from the hall.Basic function of the proportionally regulated fresh air access servo is CO2 concentration control. Additional function is the possibility of climate regulation in a hall using outside air, what saves energy (for example cooling with cold night air during the summer period). Because of that the set of regulators LB-760A is complemented with a hytherograph LB-710 installed outside of the hall (in a meteorological cage, in a place shielded from direct exposure to rainfall and sun radiation).
Regulator is equipped with an alarm output (output 6), what allows on signalling the emergency situations (probe damage, lack of power) or any situations that can be of serious danger to the cultivation (for example caused by serious variations of climate conditions in a hall from the set values). The emergency output can be attached with; for example a ring, which is going to signal the duty personnel about an emergency situation.
In case when installation composes of a larger amount of regulators LB-760A/LB-760 and a supervising PC computer (picture 3) it is possible to use only one CO2 concentration meter for the whole installation. The air from each hall is delivered in cycles to the CO2 meter using the valve system, the pipes and the air pump. Work of such measurement system has to be constantly supervised by the computer - this is the condition for the installation to work.
Using such of CO2 concentration measurement method allows on lowering the costs since only one CO2 concentration meter is required (the device is very expensive).
Device's software performs few additional special functions, such as:
Picture 3. System measurement of CO2 concentration in cultivation halls HU: CO - air collection ducts, 8...9 - LB-760a regulator control outputs (output functions: 8 - CO2 measurement, 9 - external CO2 measurement), ZP - air valves, PS - fresh air (external air CO2 measurement), KO - LB-485 converter, LB-710 - hytherograph for measurement of external air parameters, SP - CO2 measuring box (containing: FO - drainage filter, PO - air pump and DC - CO2 concentration meter), PC-S - computer controlling system operation (server), ETH - local Ethernet network, MD - modem/router, INT - the Internet, PC-K1 - additional operator position (computer in the internal network), PC-K2 - additional operator position (computer with access from outside through the Internet).The construction of the device and the computer control software were elaborated after consulting many mushroom growing experts and based on experience gained in many mushroom growing cellars throughout few years on the territory of the whole country, including the biggest mushroom growing cellar: HAJDUK in Lipinka. We guarantee 12 month warranty and full after warranty service. Software for the system is on a constant development. All users can load a free new version of software via internet.
The LAB-EL climate regulator can cooperate with all existing type of ventilation channels (air conditioning centers). When planning a new investment a lot of attention should be paid to the right solution selection; use of one heater in the ventilation channel or use of a cooler and a heater (with two independent circuits of hot and cold water). In the first case the inside air can be heated, when it comes to cooling it can be done through watering the walls or inserting in the outside air.
The outside air can be let in to the hall to keep CO2 concentration on a necessary level. The inconvenience of such solution is high humidity and too high temperature in a hall during the summer period if there is no cooling circuit (lower cost, simplified version of conditioning centres). In the second case (picture 2) warming, cooling, and drying of the inside air can be done independent from the outside air. It allows on getting full air conditioning in a hall, but it is more expensive when it comes to investment spending and exploitation (higher energy consumption). The extended version of regulator LB-760A should be applied for regulation in that case. The possibility to humidify does not change in both cases (through spraying water) and lowering the CO2 concentration level (through letting in the fresh air ).
The climate regulator LB-760A can cooperate with all of those servos, that are powered with DC supply 24V / DC or AC supply 24V / 50 Hz and have control signal output Y = 0...10 V / DC (or Y = 2...10V / DC). We especially recommend the BELIMO servos type LM24-SR with a turn moment 4 Nm. In case when larger turn moments are required or it is necessary to close air throttle with no power (returning spring) other BELIMO servos can be used for example: LF24-SR (4 Nm, returning springs), NM24-SR (8 Nm), SM24-SR (15 Nm), AF24-SR (15 Nm, returning springs), GM24-SR (30 Nm). A servo with adequate moment should be proposed by the producer of the ventilation channels.
The climate regulator LB-760A can cooperate with all inverters (frequency converters - changing single phase mains 220 V / 50 Hz for three phase mains 3 x 220 V / 0...60 Hz), that have control signal input 0...10 V / DC. The change in voltage from 0 V to 10 V should be caused by the change in the engine turn speed from the minimum (for 0 Hz) to the maximum (for 50...60 Hz). The inverter's type should match the engine's power. We recommend to agree the inverter's type with its producer (distributor). Mostly we use EUROTHERM inverters.
The basic set provided by the LAB-EL company include the following: regulator LB-760A, temperature and humidity measurement probes and the control software for the computer. As additional equipment we provide the following; the converter RS232/RS485, hytherograph LB-710, CO2 meter with equipment for the CO2 system measurement and shielded computer cables (for connecting the regulators to the computer). Purchase of a control computer, a printer and possibly a modem, should be done in a computer company close to the client's place since the warranty service should not be too far away.
The LAB-EL company also provides help in installation of low voltage circuits and system configuration (probe connection, probe calibration, parameter programming, computer connection and configuration) as well as training. The relatively low installation cost assume grower's active participation in the installation process (mechanic device assembly and wiring) and usage of grower's own actuator devices (see export price list).