Standard tests sequence used at EDF for automation

This article defines the three types of stresses used by Electricite de France to verify the aging effects on the automation equipments. Their succession is chosen so that the effects of each, favour the following one. Mechanical and thermal stresses with mechanical effect are applied first in order to age seals and components submitted to a mechanical overstress, and to verify and check the stabilization and compatibility of materials. The corrosive environments applied afterwards, do or do not reach the sensitive parts of the equipments (electronics, measure cells, contacts...) according to the conception of cabinets and their response to the previous tests. Finally, long time functional cycling allows to point out the underdimensioned components, the weakness of metallic diaphragms, the fatigue of measure cells. The test severities for each type of equipment are settled after numerous investigation test on equipments from many manufacturers, the target being to allow the selection of equipment having a sufficient resistance and a good life expectation