AL ATEX GAS – ATEX explosion-proof centrifugal fans with forward-curved impeller, up to 10,770 m³/h

AL ATEX GAS – ATEX centrifugal fans for explosive gas atmospheres

AL ATEX GAS centrifugal fans with forward-curved Sirocco-type impellers are designed for transporting clean air containing potentially flammable gases, vapours or mists in explosive atmospheres. Suitable for Zone 1, they comply with ATEX Directive 2014/34/EU. The highest maximum airflow of the catalogue-listed models is 10,770 m³/h.

Main features

• ATEX equipment category II 2G for explosive gas atmospheres in Zone 1.
• ATEX marking: II 2G Ex h IIB T4 Gb.
• Certificate: IMQ 10 ATEX 017 X.
• Forward-curved Sirocco-type centrifugal impeller.
• Scroll casing made of sheet steel with epoxy-polyester powder coating.
• Galvanised steel impellers for sizes 200–315; welded and painted steel impellers for sizes 355–450.
• Steel inlet with epoxy coating.
• Direct-drive arrangement, execution 4.
• Explosion-proof asynchronous electric motor.
• Motor protection rating IP55, insulation class F and continuous duty S1.
• PTC thermistors for motor winding protection.
• Inverter speed control for three-phase models, subject to manufacturer requirements.
• Conveyed air temperature from −20 °C to +60 °C; from −40 °C to +60 °C on request.
• 60 Hz versions and T5 or T6 temperature classes available on request.

Casing discharge positions

Standard casing position: LG270°. LG and RD discharge orientations are available in 45° increments. The 180° and 225° positions require special construction and must be specified when ordering.

Optional accessories

• Round inlet adapter.
• Inlet protection guard.
• Outlet protection guard.

Accessories are not included in the fan type-examination certificate. Their suitability for the specific ATEX installation must be confirmed with the manufacturer.

AL ATEX GAS – technical catalogue (PDF)

AL ATEX GAS – dimensions

Dimensions are in millimetres (mm); weights are in kilograms (kg). Dimension references are illustrated in the drawing below. The tables contain AL ATEX GAS data.

Connection and mounting dimensions

Dimensional drawing

The drawing illustrates the standard AL series. For AL ATEX GAS, use the dimensions and weights in the tables above, which may differ from the standard AL series.

AL ATEX GAS – technical specifications

Model performance data

P = number of motor poles; Pm = motor power; In = rated current; Qmax = maximum airflow; Pt min = minimum total pressure indicated by the manufacturer.

Qmax and Pt min for models 284 A/B and 314 A/B are shown using the combined catalogue entries for their respective size groups. Check the individual performance curve before selecting a specific model.

AL ATEX GAS – technical catalogue and performance curves (PDF)

AL ATEX GAS – installation and operation

Installation environment

AL ATEX GAS fans are intended for industrial ducted ventilation systems where explosive atmospheres containing gases, vapours or mists may occur. Before installation, verify that the selected fan's ATEX marking II 2G Ex h IIB T4 Gb is suitable for the hazardous area classification, gas group and temperature requirements.

Duct system requirements

Fans with forward-curved impellers must always be connected to a duct system. Where necessary, additional aerodynamic resistance, such as a regulating damper, must be provided. Airflow must be limited so that the motor current does not exceed the value stated on the motor rating plate.

Casing orientation

The standard casing position is LG270°. Select the discharge orientation according to the duct layout. LG and RD positions are available in 45° increments; 180° and 225° require special construction and must be agreed before ordering.

Mechanical installation

• Secure the fan to a stable support suitable for the operating loads.
• Connect ducts without transferring their weight or mechanical loads to the fan casing.
• Provide sufficient access for inspection, servicing and motor maintenance.
• Before start-up, check that the impeller rotates freely without touching the casing.
• Verify that inlet and outlet guards and other accessories are suitable for the ATEX installation.

Electrical connection

Electrical installation must be carried out by qualified personnel in accordance with the motor rating plate, manufacturer instructions and electrical requirements applicable to explosive atmospheres.

Connect the PTC thermistors to a compatible protective device. Frequency-inverter speed control of three-phase models is permitted only under the conditions specified by the manufacturer and the motor explosion-protection requirements.

Commissioning

• Check earthing, electrical connections and motor protection devices.
• Verify the impeller rotation direction.
• Check that airflow and system resistance correspond to the selected model's performance curve.
• Measure the motor current and verify that it does not exceed the rated limit.
• Check for abnormal noise, vibration or overheating.

Maintenance

Regularly inspect the impeller, casing, fasteners, motor and protection devices. Perform maintenance only after safely disconnecting the electrical supply and preventing unintended restart.

AL ATEX GAS – technical catalogue (PDF)