CBI CH Series, Перевод оригинальной инструкции

Страница: 9 / 26

8
Categories of constructive safety
The potentially explosive atmosphere can be caused by:
- Gas , potentially explosive vapours and mists.
- Dust , potentially explosive dust.
- Gas and Dust , both.
Depending on the duration of the potentially explosive atmosphere and its type,
the risk areas are defined and shared with the customer; these can differ between
inside and outside the fan.
Normally such characteristics are described and agreed upon in a separate
document attached to the contract review ( attachment Ex ).
ATEX fans can only be used in the RISK ZONE defined by the Manufacturer and
Customer upon signing this document.
ATEX fans are consequently divided into two Groups:
- Fans Group I - For installation in a pit (NOT PROVIDED and not conforming
to this manual)
- Fans Group II – Surface equipment.
ATEX fans are also grouped in three categories depending on the level of protec-
tion so that the anti-explosion safety is guaranteed:
- Category 1 in the case of rare or unusual malfunctions (NOT SUPPLIED);
- Category 2 in conditions of foreseeable malfunction; high protection;
- Category 3 in normal operating conditions; normal protection.
Correspondence table of Risk areas and Fan categories.
F
eatures
Risk
of
area
Meaning Requested type of fan
Category
Fan
corresponding
0
Presence of potentially explosive
Gas/Vapours/Mists.
Constant or long-term
Fan that
guarantees anti-explo-
sion safety even in case
of rare malfunctions
1G
(NOT SUPPLIED)
20
Presence of potentially explosive
Dust.
Constant or long-term
1D
(NOT SUPPLIED)
1
Presence of potentially explosive
Gas/Vapours/Mists.
Probable
Fan that
guarantees anti-explo-
sion safety even in case
of foreseeable malfunc-
tions
2G
21
Presence of potentially explosive
Dust. Probable
2D
2
Presence of potentially explosive
Gas/Vapours/Mists.
Rare or short-term
Fan that guarantees
anti-explosion
safety in normal operat-
ing conditions
3G
22
Presence of potentially explosive
Dust.
Rare or short-term
3D