Furuno 9ZWWR2120, Руководство по установке

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S2E-17-0209_IM_WR2120_C
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2.2. Assessment of Risk Components
Each risk component and , consists and may be expressed by the
following general equation:
where
is the number of dangerous events per annum
is the probability of damage to a structure
is the consequent loss
The number of dangerous events is affected by lightning ground flash density ( ) and by the
physical characteristics of the structure to be protected, its surroundings, connected lines and the
soil.
The probability of damage is affected by characteristics of the structure to be protected, the
connected lines and the protection measures provided.
The consequent loss is affected by the use to which the structure is assigned, the attendance of
persons, the type of service provided to public, the value of goods affected by the damage and the
measures provided to limit the amount of loss.
2.2.1. Composition of risk components
Composition of each risk components are as follows:
: Risk of loss of service to the public:
: Risk of loss of economic values:
2.2.1.1. Risk components for a structure due to flashes to the structure
: Component related to physical damage caused by dangerous sparking inside the structure
triggering fire or explosion which will also endanger the environment. All types of loss (L1, L2, L3
and L4) will arise.
: Component related to failure of internal systems caused by lightning electromagnetic impulse
(LEMP). Loss of type L2 and L4 could occur in all cases along with type L1 in the case of
structures with risk of explosion, and hospitals or other structures where failure of internal
: Component related to failure of internal systems caused by LEMP. Loss of type L2 and L4
could occur in all cases, along with type L1 in the case of structures with risk of explosion, and
hospitals or other structures where failure of internal systems immediately endangers human life.
2.2.1.2. Risk components for a structure due to flashes to a line connected to the structure
: Component related to injury to living beings caused by electric shock due to touch voltage
inside the structure. Loss of type L1 and, in the case of agricultural properties, loss of type L4 with
possible loss of animals could also occur.
: Component related to physical damage (fire or explosion triggered by dangerous sparking
between external installation and metallic parts generally at the entrance point of the line into the
structure) due to lightning current transmitted through or along incoming lines. All types of loss (L1,
L2, L3 and L4) will occur.
: Component related to failure of internal systems caused by overvoltages induced on incoming
lines and transmitted to the structure. Loss of type L2 and L4 could occur in all cases, along with
type L1 in the case of structures with risk of explosion, and hospitals or other structures where
failure of internal systems immediately endangers human life.
2.2.1.3. Risk components for a structure due to flashes near a line connected to the structure
: Component related to failure of internal systems caused by overvoltage induced on incoming
lines and transmitted to the structure. Loss of type L2 and L4 could occur in all cases, along with
type L1 in the case of structures with risk of explosion, and hospitals or other structures where
failure of internal systems immediately endanger human life.