Causes of Aging

Introduction

Switchboards and switchgear age whether they are in operation or not. Aging is due primarily to the influence of the environment and the operating conditions.

Influence of the Environment

A device placed in a given environment is subjected to its effects. The main environmental factors that accelerate device aging are:

• Temperature

• Percent load

  @Writer (09/2016): info for Translation phase: Percent load (EN) = Taux de charge (FR) (see LVPED508016FR-02 - 07/2013).

• Relative humidity

• Salt environment

• Current harmonics

• Dust

• Corrosive atmosphere

• Vibration

• Operating cycles

• Interrupted currents

The tables in this chapter summarize for each factor:

• Why it is harmful: influence

• How to identify it: appearance

• Impact on operation: consequences