Course detail
Diagnostics and Electrical Equipments Protections
FEKT-MPA-DJZAcad. year: 2022/2023
Faults and protections against overcurrents in electrical equipments. Protective devices and their characteristics. Protection of cables and wires aganist overloads and short circuits. LV motors and generators protection. Protectin devices for transformers, capacitancies, batteries etc. Usage of switchgears in switgear assemblies. Protection of semiconductors. Overvoltage protection devices. Protection against electric shock, residual current devices.
Language of instruction
Number of ECTS credits
Mode of study
Guarantor
Offered to foreign students
Learning outcomes of the course unit
- principal of function of various protective devices
- principals of protection against overcurrents for individual kinds of devices
- principals of selectivity determination
- principals of protection against electric shock
- principals of overvoltage protection
Students can explain
- meaning of parameters of protective devices
- phonemena influencing design of protection for electric devices
- kinds of selectivity between protective devices
- principals of individual protective provisions for protective measure automatic disconnection of supply
- overvoltage origin and protection against it
Students are able to design
- cables protection against overload and short circuit
- protection of motors and inlets to them
- protection of transformers
- protection of semiconductors
- protection of capacitive bateries
- selectively connected protection devices in series
- electric circuit from the automatic disconnection of supply point of view
- individual levels of overvoltage protection
Students are able to analyse
- effects influencing protection of electric devices
- effetcts of short-circuit currents
- appropriate usage of protective devices
Students are able to judge
- correctness of overcurrent protection of electric devices
- selectivity between protective devices
- protection of surge arrestors
- fulfillment of conditions for protective measure automatic disconnection of supply
Students are able to compose
- report concerning protection of electric devices
- protocol on short circuit calculation
- protokol on measurement of important parameters of protective devices
Prerequisites
Requested knowledge:
- to solve electrical circuits by the method of circuit simplification and nodes potentials
- knowledge of electrodynamic forces effects and calculation
- knowledge of thermal effects of electric currents in steady state and during transient period
- calculation of short-circuit currents in LV networks
- classification of electrical switching devices based on the ability to switch various currents
- phonemena during motor start
- function of a transformer
- knowledge of regulation 50/1978 Sb.
Co-requisites
Planned learning activities and teaching methods
1. Lectures on each subjects (P1-P13).
2. Lectures are practised during numerical, computer and laboratory tasks every week.
3. All texts are available in faculty system.
Assesment methods and criteria linked to learning outcomes
Course curriculum
2. Parameters and characteristics of fuses
3. Parameters and characteristics of circuit breakers and other protective devices
4. Wires protection against overload
5. Calculation of short-circuit currents and wires protection against short-circuit currents.
6. Motor and motor inlets protection
7. Transformer protection
8. Protection of semiconductors and other devices
9. Protection of capacitor bateries, usage of switchgears in switchgear assemblies
10. Selectivity between protective devices
11. Protection against electric shock
12. Protection against overvoltage
13. Excursion
Work placements
Aims
Specification of controlled education, way of implementation and compensation for absences
Recommended optional programme components
Prerequisites and corequisites
Basic literature
Dunning J.: The Fundamentals of Circuit Breaker & Protection Maintenance, ISBN: 9781519258410 (EN)
NCCER: Circuit Breakers and Fuses TG, ISBN: 9780132661393 (EN)
Ragunath Ram: Electrical Protection Systems & Units: Protection Devices Guide (EN)
Recommended reading
Elearning
Classification of course in study plans
Type of course unit
Lecture
Teacher / Lecturer
Syllabus
Failures and types of faults
Protection devices basic characteristics
Fuses, characterics and applications
Short-circuit currents evaluation.
Protection of lines.
Protection of electric motors.
Protection of transformers.
Protection of semiconductors.
Computarized protections
Selectivity of protection devices
Protection against electric shock
Protections against overvoltages
Exercise in computer lab
Teacher / Lecturer
Syllabus
PC aided selectivity design.
Laboratory exercise
Teacher / Lecturer
Syllabus
Electrical switch voltage test.
Losses of a fuse.
Test of el. device switching time.
Thermal relay characteristic measurements.
Practical test of sectivity in laboratory circuits
Connection and test of overvoltage protection <BOD<Test of microprocessor protection
Impedance loop calculation and meassurement
Residual current device testing
SPACOM protection using and simulation
Elearning