Current transformers are specific transformer types used for current measurement. The common engineering laws are also valid for the current transformers. The most important roles of current transformers are: - To transform currents, from a high value to a value that can be easily handled by protection relays and associated instruments - To separate and insulate the metering circuit from the high voltage - To provide options for standardization of instruments and protection relays with rated currents This course is suitable for engineers with a desire to understand the fundamentals of current transformers. Presented details cover issues related to measurement error, protection and measurement cores, accuracy classes, core selection and necessary technical requirements that current transformers have to meet. Upon successful completion engineers will be able to address various current transformer terms, specific classes, application purposes and overall core selection process. Learning Objectives Specific Knowledge or Skill Obtained

• Current transformer measurement error
• Metering cores
• Protection cores
• Current transformer core selection
• Current transformer technical requirements
• Current transformers specific requirements for different relay protection applications