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close this bookCircuits, Formulas and Tables Electrical Engineering - Basic Vocational Knowledge
View the document(introduction...)
View the documentPreface
Open this folder and view contents1. Selected Graphical Symbols of Electrotechnology
Open this folder and view contents2. Bell Circuits
Open this folder and view contents3. Basic Circuits of Illumination Engineering
Open this folder and view contents4. Electrical Machines
Open this folder and view contents5. Contactor Circuits
Open this folder and view contents6. Rectifier Circuits
Open this folder and view contents7. Measurement Circuits
View the document8. Protective Circuits
Open this folder and view contents9. Circuits in Motor Vehicles
View the document10. Tables
Open this folder and view contents11. Basic symbols and formulas of electrical engineering

8. Protective Circuits


Protective wire in a three-phase current system


Earthing (Three-phase a-c three wire system)


Earthing (Three-phase a-c four wire system)

Protective Earthing


Reflux of the leakage current via water pipe system (1)


Reflux of the leakage current via earth

IF leakage current, In rated current of the fusible cut-out


Circuit for Generating Protective Low Voltage

Fault-voltage Protective Circuit


in a three-phase three-wire system

1 fault-voltage circuit breaker

Fault-current Protective Circuit


in a three-phase four-wire system

1 fault-current circuit breaker