NF C26-221

Methods of testing isulating materials. Test methods for evaluating resistance to tracking and erosion of electrical insulating materials used under severe ambient conditions.

Cette norme développe deux méthodes d'essai permettant de mesurer la résistance au cheminement et à l'érosion des matériaux isolants en faisant appel à un contaminant liquide et à des éprouvettes planes inclinées. Les méthodes se distinguent par la tension appliquée: essai à tension constante ou essai par paliers de tension. Pour chacune des méthodes, deux critères de fin d'essai sont décrits dont un est préférentiel.

To comply with a standard, you need to quickly understand its issues in order to determine its impact on your activity.

The Requirements department helps you quickly locate within the normative text:

• mandatory clauses to satisfy,
• non-essential but useful clauses to know, such as permissions and recommendations.

The identification of these types of clauses is based on the document "ISO/IEC Directives, Part 2 - Principles and rules of structure and drafting of ISO documents" as well as on a constantly enriched list of verbal forms.

With Requirements, quickly access the main part of the normative text!