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1
Types Of Chambers Climatic simulation Used to test the reliability & performance of components and assemblies under various conditions of temperature, humidity, altitude, vacuum and vibration.
• Thermal stress/shock screening Used to produce rapid changes in temperature to screen out potentially faulty components and sub-assemblies.
• Plant growth test chambers/roomsUsed in horticultural research labs to set standard growing conditions for testing fertilizers etc.
Environmental Chambers
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Related applications
•Brick and ceramic drying rooms•Mushrooms farms•Cheese maturing rooms•Incubators - eggs, antibiotics•Fruit and meat storage rooms
Environmental Chambers
These all involve the control of temperature, humidity and sometimes CO2, solar energy. They are really all environmental chambers.
Environmental Chambers
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Typical Chamber.
Temp probe
Humidity probe
Water Spray
Humidification
Compressor
Cooling/dehumidify
HeatingHeaters
X26
By-passCooling/dehum
coils
Environmental ChambersEnvironmental Chambers
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Example plant growing chamber.
Control & Data Acquistion of:• Temp, %RH, CO2 and day/night simulation
Recorder
TempPID Loop
HumidityPID loop
_
_Temp
_
C02PID loop
%RH
C02
Control OP
Control OP
Control OP
ToolkitBlocks
Light SP
Temp SP
%RH SP
C02 SP
Time
Plant Growth Chamber
26/2704
Example plant growing Chamber
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•Brick, tiles drying room
The purpose of drying is to extract water so that the product does not crack during the firing process. The aim is to achieve this as quickly as possible without cracking the product during the drying process. Typically both temperature and humidity are controlled.
This process can take from 3 days to 3 weeks depending upon the product type
Bricks & Ceramics
Example - brick or tile drying room
2 weeks
Temp
Humidity
30C
20C
Example Brick Drying Room
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Control methods
• Heating is usually electrical
• Cooling and dehumidification is normally performed using compressors
• Fast cooling is typically provided by liquid nitrogen
• Humidification is achieved using either steam or atomised water sprays
Environmental ChambersEnvironmental Chambers
Recorder Values
• Temperature, Humidity, Dewpoint, Atmosphere, Light, Vibration
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Equipment usedThermal shock and stress chambers - 2408/2404 programmable controllers
- solid state relays- Recorders
Temperature and humidity chambers - 2408/2404 programmable controllers
- X26 chamber controller- 2604 and 2704 advanced 3-
loops- T800, 2500 - solid state relays- Recorders
Environmental ChambersEnvironmental Chambers
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Environmental Chambers
Cooling by-pass
X26 Control block diagram
Humidity Function Block
Hum
PID%RH
Humidity probe input
Wet bulb temp
Humidify op
Dehum opOP
Boost Heat SP Boost heat
OPBoost Cool SP
Boost cool OP
Temp (dry bulb)
Temp
PID
Heating opCooling op
Compressor On
Min-On Timer
Event 1
Event 2
Setpoint Programme
r
Temperature SPHumidity SP
reset
Event outputsrun
Clock
ORhold
OP
>0
> Drain valve
AND
1C/33 F
>0
Environmental Chambers
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Who uses them?Primarily:
• Avionic companies for testing Satellite and aircraft equipment
• Cars manufacturers
• The defence industries - for guns, tanks, telecomms
• Semiconductor manufacturers
• Horticultural research establishments
• Biological test laboratories
Environmental ChambersEnvironmental Chambers
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Eurotherm Advantages• Tailored product in the X26 - use out of the box
• Wide range of solutions - 2400 programmers, 2604, 2704,
• Solid State Relays
• Paper & Paperless Recorders
• 2500 offers front end to PLC - reducing system wiring and improving control.
• Humidity function block, Recorders and 26/2704
• Fast digital communications- Modbus, Devicenet
• Large installed base
Environmental ChambersEnvironmental Chambers