EN 61543 deals with the electromagnetic compatibility (EMC) requirements for residual current-operated protective devices (RCDs) used in household and similar applications. The standard outlines the necessary performance criteria and testing methods to ensure that RCDs operate reliably in the presence of electromagnetic disturbances. It aims to ensure that these devices do not interfere with or are not adversely affected by other electronic equipment in residential or similar settings, thereby maintaining their protective functions and contributing to overall safety and reliability in electrical installations.