Introduction

This Test Specification describes an environmental cycle test from Volkswagen AG and cycles between high and low test temperatures during a repeating 12 hour cycle. It is primarily used for testing units, e.g. vehicle parts in the engine compartment.

The behavior of the  parts during environmental cycle stressing by means of cycling temperature and moisture shall be assessed here (e.g. susceptibility to cracks, deformation, separation of the composite material, etc.).

The purpose of the test specifications (e.g. temperature -40 °C) is to uncover component weaknesses in a short-term test with accelerated time effect, not to define general component requirements for continuous operation.

Test Conditions & Method

A 12 hour cycle (720 mins)

• Step 1 - 1 hour (60 min) heating phase to +80 °C and 80% rel. humidity,
• Step 2 - 4 hours (240 min) holding time at +80 °C and 80% rel. humidity
• Step 3 - 2 hours (120 min) cooling phase to -40 °C, when freezing point is reached: approx. 30% rel. humidity, the air humidity remains unregulated as of T < 0 °C (depending on the system, humidity regulation can also be suspended as of T < 10 °C)
• Step 4 - 4 hour (240 min) holding time at -40 °C, air humidity remains uncontrolled
• Step 5 - 1 hour (60 min) heating phase to +23 °C, rel. humidity is regulated to 30% as of T = 0°CThe tolerances around the set values are as follows:
• Temperature Tolerance ± 2°C
• Relative Humidity ± 5%

 

Download the Test Methodology here

 

This test can be ran in its entirety in an Ascott Cyclic Corrosion chamber fitted with Dehumidification Unit (Ref ACC29 -40°C), Ultra heater blower system to +80°C (ref ACC47) including Atmosfar Premium -40°C Chambers