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close this bookProtective Measures against Hazardous Contact Voltage - Course: Basic skills and knowledge of electrical engineering. Trainees' handbook of lessons (Institut für Berufliche Entwicklung, 23 p.)
View the document(introduction...)
View the documentIntroduction
View the document1. The Necessity of Protective Measures against Hazardous Contact Voltage
View the document2. Potential Equalization
close this folder3. Protective Measure against Hazardous Contact Voltage
View the document(introduction...)
View the document3.1. Protective Measures Preventing the Development of Hazardous Contact Voltage
View the document3.2 Protective Measures which Prevent that Hazardous Contact Voltages Continue to Exist

(introduction...)

These are subdivided in two groups.

Group 1: Protective measures preventing the development of hazardous contact voltage.

- protective insulation
- protective low voltage
- protective isolation
- protective conductor system

Group 2: Protective measures which prevent that hazardous contact voltage continue to exist.

- protective earthing
- connection to neutral
- fault-voltage protective system
- fault-current protective system
- isolating fault-current protective system

If the protective measures are categorized with respect to the presence of a protective conductor, the following subdivision results:

Protective measures "without" protective conductor

- protective insulation
- protective low voltage
- protective isolation

Protective measures "with" protective conductor

- protective conductor system
- protective earthing
- connection to neutral
- fault-voltage protective system
- fault-current protective system
- isolating fault-current protective system

Technical terms recurring with the individual protective measures have to be used according to Figure 3:

- contact voltage (1)
- fault-voltage (2)
- fault-current (3)
- body resistance between current entry and exit points (4)
- transition resistance of the station point (5)
- resistance of earth (ground) (6)
- resistance of earth bus (7)


Figure 3 - Fault-current circuit - 1 contact voltage, 2 fault voltage, 3 fault current, 4 body resistance between current entry and exit points, 5 transition resistance of station point, 6 resistance of the ground, 7 resistance of earth bus