Walk-In Altitude, Temperature & Humidity Chamber (CATH))




Aerospace & Defence applications demand high reliability under mixed environmental conditions where Pressure, Vacuum, Temperature & Humidity constantly affect a component’s performance. Our 3000 Litre combined Altitude, Temperature & Humidity (CATH) chamber simulates pressure up to 30 mbar in its test space between temperature range of -70°c to 100°c and humidity range of 10%RH to 95%RH, with average rate of cooling not less than 2.5°c per minute and average rate of heating not less than 3°c per minute. The test chamber can reach 30 mbar from ambient pressure in one 1 hour while maintaining the temperature of -20°c .









Exterior Surface
  • Its an RRU construction with outer material primed with phosphate. RAL 7035 epoxy based electrostatic powder coating for a good aesthetic look. The exterior surface have high wear resistance.
  • Leveling pads are be provided for installation.
Test Space
  • The inner chamber is constructed using AISI-304 grade of stainless steel polished with a brushed finish.
  • The test space is insulated using multi layered mineral wool. This mineral wool have a low `k’ factor and high density of up to 48Kg/m3. This insulation is non hygroscopic in nature and asbestos free.
Chamber Door
  • Door is designed to open pneumatically. A separate  compressor is provided for the door opening system.
  • Spring loaded latch is provided with a locking facility. The inner surface of the the door is pre-polished stainless steel and a micro switch is provided for an interlock between the conditioning fan and the door opening. Door opening system shall have manual opening as well as programmable.
Viewing window & Lighting
  • Viewing Window of 300 cm x 300 cm, multi panes glass is provided with suitable heaters to provide visibility of test unit during all tests
  • The semi hermetic compressor is used with flame proof enclosure. The compressor is mounted on anti vibration pads.
  • A water chiller condenser specially designed for tropical climates is driven by a co-axial fan. The chiller unit will have a DM plant. The heat exchanger coils is with Inner grooved copper tubes and be finned for maximum heat transfer. Hot gas bypass systems is used for protection against No-Load condition and superior stability and control in temperature.
  • Oil return system is used for protection against oil migration from the compressor. Other than the Chamber and Control unit, remaining systems like, Chiller, refrigeration system, water softner & air compressor is installed outside of the bay.
  • A low-pressure droplet free vapour boiler of SS 304 with water level indicator and direct vaporization system is used.
  • Float switch is provided inside the boiler to maintain the water level in the boiler through makeup solenoid valve.
  • Heater safety thermostat is provided on the boiler to protect the heater failure in case no water.
  • The wick tank water level is automatically maintained through a water solenoid valve and an electrical float switch.
  • Refrigeration based de-humidification coils are used. The desired level of lower humidity is achieved based on maintaining the precise dew point temperature. The output shall automatically be activated on the set point as well in ramp up mode after a low temperature cycle.
  • Fault Diagnostics system with history.
  • Complete or circuit relevant protection based on fault with audio-visual alarm.
  • Independent temperature protection for test specimen (T max & T min)
  • Software temperature limiter for min./max. test chamber temperature.
  • Protection for excess pressure in refrigeration circuit.
  • Automatic oil return for safety of compressor. Bypass protection at No-Load conditions.
  • Under Voltage, Over Voltage, Single Phase protection and phase reversal at input.
  • Protection for overloaded motor of test space fan and compressors (Thermal Overload Relay).
  • The control and monitoring system will be protect against input electrical surge and spike.
  • Common Earth point is provided.
  • Low water level protection is provided with an electrical float switch
  • Low water level protection shall be provided with an electrical float switch. Digital time totalizer shall be provided to monitor the usage.
  • An emergency stop switch is provided. Thermal cut out, in master-slave configuration  shut down the chamber in case of temperature exceeds the set temperature along with audio – visual alarm at the control panel and in the control room at a distance of about 150 meters away from the chamber.
  • The control panel to be equipped with suitable smoke detector / fire alarm.












Test Space Dimension (WXDXH) (mm)

1500 X  1500 X 1500

Test Space Volume (L)


Temperature Range (°C)

-70 to +100

Temperature Fluctuation (°C)

0.1 to 1

Ramp Rate (°C/min)


Humidity Range (%RH)

10% – 95% RH

Humidity Fluctuation (%RH)

1%RH  to 3%RH