al-ko prospekt at4-atex engl

8/9/2019 Al-ko Prospekt At4-Atex Engl

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AIR-HANDLING-UNITAT4 COMPLIANT WITH EUGUIDELINE ATEX 95

SAFETY CERTIFIED QUALITY

AIR-HANDLING-UNITS



ATEX 95 unit categories

According to the ATEX guideline (94 / 9 /

EG), units are grouped into categories

for use in the corresponding zones.

There are three different unit categories

for the unit group II, which correspond

to the different zones. This makes it

possible to associate explosion-proof

products with operational Ex zones.

Category 1 includes units for zones 0

and 20 (very high degree of safety).

AT4-classification

Category 2 includes units that are struc-

turally designed so that they can be

operated in compliance with the para-

meters furnished by the manufacturer

and assure a high degree of safety. Units

of this category can, upon approval, be

operated in zones 1 and 21.

Category 3 includes units that are struc-

turally designed so that they can be

operated in compliance with the para-

meters furnished by the manufacturer

and assure a normal degree of safety.

Units of this category can, upon appro-

val, be operated in zones 2 and 22. DIN

EN 50281-1-2 differentiates between

conductive and nonconductive dust.

When there is conductive dust in zone

22, equipment from category 2 D must

be used.

EX-suitable unit components

I EX models of direct-driven fans for

zone 1 to T4 or 21 to T 120 °C com-

bined with a pressure-tight encapsu-

lated motor

I belt-driven EX fans for only zone 2

and temperature class T3!

I electrically conductive fan drive belt

I flexible connection made of electric-ally conductive material

I air filter cannot be statically charged

– for Explosionsgroups (IIA – IIC)

I inspection portholes made of glass

I drip eliminator cannot be statically

charged – new development

I all electrical components ATEX-

certified, all mechanical components

with manufacturer confirmation

I unit construction is completely

earthed

I earthing of louvre damper vanes

I run around coil system or plate heat

exchanger can be used for heat

recovery

CE II 2G / D c IIC T4 (x)



Unit situated inside the EX-zone

I dischargeable flexible connection

I earthed damper vanes

I electrically conductive filter G4 – H13

I heat recovery provided by a run

around coil system or heat recovery

I electrically conductive droplet eliminatorI EX models of direct-driven fans for zone

1 to T4 or 21 to T 120 °C combined with

a pressure-tight encapsulated motor

I belt-driven EX ventilators only for zone

2 and temperature class T3

I drive motor encapsulated in pressure-

tight fashion with FC = frequency

converter operation

I sound absorber

I weatherproof grille at exhaust

Unit design 1

Exhaust air unit situated outside

EX-zone

Same components as in unit design 1

Unit design 2

Intake and exhaust air unit situated

inside the EX-zone

I intake and exhaust air units must

be EX-models

I all electrical components must be

EX- models

Unit arrangement

Intake and exhaust air unit situated

outside the EX-zone

I exhaust air unit must be an EX-model

I intake air unit (EX-model not required)

with louvre damper at air outlet to

prevent return flow

I electrical components situated

outside the EX-zone do not have to be

EX-models

for zone 1, T3 to T4,

or zone 21 to T 120 °C

for zone 2, T3



AL-KO THERM GmbH

Hauptstraße 248-250

89343 Jet tingen-Scheppach

Phone (+49) 8225 / 39- 269

Fax (+49) 8225 / 39- 271

E-mail [email protected]

www.al-ko.com

al-ko prospekt at4-atex engl

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