System

Definition of System Protection Schemes (SPS)A System Protection Scheme (SPS) or Remedial Action Scheme (RAS) is designed to detect abnormal system conditions and take predetermined, corrective action (other than the isolation of faulted elements) to preserve system integrity and provide acceptable system performance.CIGRE TB 187, June 2001 Earlier known as Special Protection SchemesWhat is special today may be common tomorrow.Other than equipment protectionNow formally known as System Integrity Protection Schemes (SIPS).