FUNDAMENTAL RULES FOR PROTECTION AGAINST ELECTRIC SHOCK 29
5.
The current can pass through the human body either case touching live parts of
different potential case standing the place with some potential and touching live part
with different potential. This first step protection, which has be
provided during the normal service electrical equipment and/or electrical installation, called
protection against direct contact basic protection protection under normal conditions.g.
. when basic insulation fails), are called exposed conductive parts. This the usual way of
protection against direct contact overhead transmission lines.e.
For that reason the first task prevent anybody (persons livestock) from touching
dangerous live parts.) electrical installation.
In the course many year utilization electricity, system protection against electric
shock has been developed. That called single fault
condition and, such case, the called protection against indirect contact has be
provided. live parts electrical
household appliances are covered enclosures) means barriers obstacles around the
live parts larger equipment electrical substations. The conductive parts electric
equipment that can touched and that are not normally live, but may become live case of
fault (e.g.g. FUNDAMENTAL RULES FOR PROTECTION AGAINST ELECTRIC
SHOCK
As mentioned the previous text, case touching live part, that means part with a
potential different from the potential earth, current flows through the body from the live part
to the earth.e. The other potential, i. the potential the live parts, usually
potential compared with the zero potential the earth. The other possibility how provide
protection against direct contact situate live parts out reach. called the voltage live parts. under single fault condition.
This protection usually provided means insulation live parts (e. This has provided during the whole life electrical equipment
(household appliances etc. conductors are
insulated) means enclosures which live parts are situated (e. One these different potentials usually potential earth, which we
consider equal zero.
The protection can achieved one the following methods:
- preventing current from passing through the body any person any livestock;
- limiting the current which may pass through body value lower than the current. That means contact with parts that are not live during the normal service and may
become live case fault, i.
During the normal service may come such case that the insulation may disrupted or
that the metal enclosure may come contact with live parts. The main objective this protection ensure that persons and
livestock shall protected against dangers that may arise from the contact with live parts the
electrical equipment installation
