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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