BS EN 60068-2-1 deals with cold tests applicable to both non heat-dissipating and heat dissipating specimens. For non heat-dissipating specimens, Tests Ab and Ad do not deviate essentially from earlier issues. Test Ae has been added primarily for testing equipment that requires being operational throughout the test, including the conditioning periods.
The object of the cold test is limited to the determination of the ability of components, equipment or other articles to be used, transported or stored at low temperature.
The cold tests are subdivided as follows:
Cold tests for non heat-dissipating specimens
• with gradual change of temperature, Ab;
Cold test for heat-dissipating specimens
• with gradual change of temperature, Ad,
• with gradual change of temperature, specimen powered throughout, Ae.
The procedures given in this standard are normally intended for specimens that achieve temperature stability during the performance of the test procedure.
Temperature chamber(s) are constructed and verified in accordance with specifications IEC 60068-3-5 and IEC 60068-3-7.
Further guidance for dry heat and cold tests can be found in IEC 60068-3-1 and general guidance in IEC 60068-1
Contents of BS EN 6008-2-1:2007 include:
Scope and object
Normative references
Terms and definitions
Application of tests for non heat-dissipating specimens versus tests for heat-dissipating specimens
Ascertaining high or low air velocity in the test chamber
Non heat-dissipating specimens
Testing of heat-dissipating specimens
Temperature monitoring
Packaging
Diagrammatic representations
Test description
Test Ab: Cold for non heat-dissipating specimens with gradual change of temperature
Test Ad: Cold for heat-dissipating specimens with gradual change of temperature that are powered after initial temperature stabilization
Test Ae: Cold for heat-dissipating specimens with gradual change of temperature that are required to be powered throughout the test
Energizing the specimen
Test procedure
Confirmation of performance
Working space
Thermal radiation
Specimen with artificial cooling
Mounting
Severities
Temperature
Duration
Preconditioning
Initial measurements
Conditioning
Intermediate measurements
Final temperature ramp
Recovery
Final measurements
Information to be given in the relevant specification
Information to be given in the test report
Block diagram tests A: Cold
Normative references to international publications with their corresponding European publications
BS EN 60068-2-1:2007 replaces BS EN 60068-2-1:1993, which has been withdrawn.