Course Description
This course will review of Over Current Protective Devices (OCPD) and their application. We will review overloads, short circuits and ground faults. The course will cover OCPD equipment, fuses breakers and relays. Review and understand time inverse curves how it works with fuses and breakers. Inrush current will be discussed to understand the need for proper overcurrent devices for motors, transformers and power electronic equipment. We will review references in the NEC of Overcurrent Protection (Article 240) Interrupting Ratings, available fault current and short circuit current rating in other parts of the code. We will review calculating fault currents in electrical systems. This will provide an understanding of protection coordination and when things do not operate as expected. Using breaker time inverse curves to understand breaker selection and how a fault prorogates in an electrical system. We will review the breaker setting on module type breaker with continuous, time delay and instantaneous pickups. We will discuss GFCI (Ground Fault Circuit Interrupters) and GFPE (Ground Fault Protection of Equipment) equipment and the differents and function of theses devices. We will review AFCI (Arc-Fault Circuit Interrupters) devices the function and operation of these devices. The course will provide an understanding and application of Over Current Protective Devices (OCPD).
Course Material
Presentation in Power Point
Course Outline
Basic Fundamentals
-
- Ohms Law
- Overload
- Short Circuit
- Ground Fault
- OCPD Equipment
- Fuses
- Types
- Breakers
- Types
- UL 489
- Relays
- Fuses
- Time Inverse Curves
- Types of Breaker Tripping Curves
- Inrush Current
- Motors
- Transformers
- Power Electronics
- References in the NEC
- Overcurrent Protection
- Interrupting Rating
- Available Fault Current
- SCCR (Short Circuit Current Rating)
- Fault Current
- Infinite Bus
- Primary Fault Current
- Calculation of Fault Current
- Conductor Impedance
- Motor Contribution
- Waveforms
- Motor Protection
- Article 430
- Short Circuit
- Overloads
- Service Factor
- Fuses and Heaters
- Breaker Coordination
- Time Inverse Curve Reviews
- Breaker Selection
- Fault Locations
- Breaker Settings
- Continuous Amps (Ir)
- Long – Time Delay
- Short – Time Delay
- Short – Time Pickup
- Instantaneous Pickup (some time not adjustable)
- Ground Fault Pickup
- Ground Fault Time Delay
- GFCI Protection
- Personnel
- Equipment
- GFPE
- AFCI Protection
- Types of Faults
- Combination
- Dual-Function
- Sensing and Operation
- Other Breaker Protective Modes
Course Objectives
This course should help qualified individual understand Over Current Protective Devices and the function of the devices. How they are categories and the theory of the function of the device with current flow. The course will provide the knowledge of time inverse curves terms, and UL characterization of equipment. The individual should have a better understanding the types of Over Current Protection Devices and their function in the electrical system. Understanding fault currents in the system will provide the individual of proper application and proper function of OCPDs, how they are categorized and the theory of the function of the device with current flow. The course will provide the knowledge of time inverse curves terms, and UL characterization of equipment. The qualified individual should understand the circuit and how these devices can be applies in the field and proper function.
