Two Zone Thermal Shock Test Chamber

Purpose

The Chamber is used to carry out Thermal Shock Test for screening of electronic components and reliability testing of instruments/equipments by generating mechanical stress as a result of sudden change in temperature.

Understanding the Standards and Establishing the Requirements:

• This is our humble try to educate our clients and it will help to finalize their specifications to procure appropriate test chamber.
• Kindly read MIL-STD-202/810/883, IS 9000 (Part 14) and JSS 55555 (Test No. 22) and select appropriate
• Selecting temperature range is not the issue.
• Specimen transfer time and recovery of temperature after transfer of specimen is a major issue.
• Most of the standards suggested their transfer time with respect to use of individual hot chamber and cold chamber. Many of them have suggested avoiding ambient condition to transfer. In many cases we have to understand the language “Maximum five minutes” means minimum can be “five seconds” also.
• Thermal shock Test means sudden change of temperature. It means that if anyone is holding test specimen at ambient condition, test severity is decreasing proportional to time hold at ambient.
• Thermal Shock Tests are recommended for two purpose i.e. component screening by some standard and instrument testing by other standards. Some standards have not clearly specified its use.
• Standards identify such test either as Thermal Shock, Thermal Cycling or Thermal Cycling (Thermal Shock) testing but we will call it Thermal Shock Testing only.

There are many matters required clarifications and proper understanding. Therefore, we request our clients to read the applicable standards in detail. If required kindly discuss with us.

Temperature Range: Hot Zone: (Ambient +15⁰) C to -73⁰ C (Specify your testing range) Cold Zone: (Ambient -20⁰) C to +220⁰ C (Specify your testing range)

STANDARD SIZE OF CHAMBERS Table-1

Final Model	Basket Size  (W x D x H)	Equivalent Steel Test Load		No. of Selves
		Component#	Equipment@
ENV-041-100 Liter	40 x 50 x 50 cm	0.1 Kg	10 Kg	1
ENV-041-180 Liter	60 x 60 x 50 cm	0.25 Kg	25 Kg	2
ENV-041-320 Liter	80 x 80 x 50 cm	0.50 Kg	50 Kg	2
ENV-041-CB	Custom Built (Specify H x W x D)	Specify	Specify	Specify
# Temperature recovery rate is 5 min (In case of IS 9000-Part -14, applicable for   dwell time 1 hour and above as is suggesting recovery time 10% of the dwell time) @ Temperature recovery rate is not recommended in any standard for testing of instruments/equipments

Standard Features:

• Thermal shock medium: Air to Air
• Construction concept: Vertical (Horizontal for large size basket)
• Basket movement: Pneumatically
• Dwell time for basket in each zone: 5 min to 180 min (3 Hours)
• Single stage refrigeration system is used up to -25⁰ C and cascade refrigeration system is used below -25⁰
• Temperature sensing by Pt-100 sensor
• Control accuracy: Better than +/- 1⁰ C
• Heating and cooling rate: Approximately 3⁰ C/min – Average
• Two selves are provided in basket
• Multilayer observation window with illumination for hot zone only
• Defrosting arrangement for cold zone.
• Door side of cold zone is covered by a SS sheet to avoid infiltration of moisture. It is reducing defrosting interval drastically.
• Air cooled for AC lab operation. Otherwise water cooled condenser is recommended.

Control Instrumentation Options (Select):

• EUROTHERM Programming controller, Model-2404
• HMI-PLC based programming controller (WATLOW or EUROTHERM)

Optional Accessories:

• Two channel Paperless chart recorder
• Two channel data logger

Major Safety Protection:

• Independent workspace over temperature protection for hot zone
• Motor winding over temperature protection for semi sealed refrigeration compressors
• High discharge and low suction pressure correction before tripping
• Refrigeration compressor tripping abnormal high discharge and low suction pressure
• Low water level in humidity generation system
• Over current Relay (OLR) and MCBs are provided as required
• Low air pressure

Power Supply:

• 415 Volt – 50 Hz – 3Φ – N – E

Provide Minimum Information While Rising Inquiry to Get Precise Quotation:

• Select final model number from Table 1.
• Specify temperature range of Hot zone and Cold zone
• Type of controller (Select from above)
• Optional accessories (Select from above)
• Basket size (Width x Depth x Height) and test load in case of Model: ENV-041-CB

Specify any additional facilities if needed