Protection against intentional contact
(protection obstacles, placing out reach) intended for applying rooms with electrical
equipment where only skilled instructed persons are permitted entry.
Figure 5.3
Fundamental principle residual-current
protective device
T test button
CT current transformer
R release, trip coil
M mechanical lock
C contact switching device
.
5.1.5 Use protective measures
Protection against unintentional contact (protection insulation barriers enclosures) is
applied electrical equipment, especially household electrical appliances, used ordinary
persons without any electrotechnical qualification).
The application residual current protective devices very important protective
element leads the necessity show the function these devices (see Figure 5.1.1. The use obligatory many countries for electrical installations in
bathrooms, construction sites, and outdoor space.FUNDAMENTAL RULES FOR PROTECTION AGAINST ELECTRIC SHOCK 33
5.
The fundamental principle residual-current protective device is: the total amount of
current flowing and from any electrical equipment zero (null), that means, normal use, no
difference.1.3).6 Additional protection
Besides these traditional types protection which international standards are considered
as usual types protection, there exists the protection very sensitive residual-current
protective devices. This protection may used additional protection fundamental types
shown above
