Why Choose the Finder 7F.21.8.120.4400 Reverse Flow Filter Fan?
The Finder 7F.21.8.120.4400 is a high-performance 120 V AC reverse flow filter fan designed for effective ventilation of industrial electrical cabinets, switchboards and automation control enclosures. Part of the Finder 7F Series, this Size 4 fan provides a nominal 400 m³/h free-air airflow at 50 Hz and is specifically configured to extract warm air from electrical enclosures.
Unlike conventional intake filter fans, the Finder 7F.21 reverse flow configuration is designed for exhaust ventilation. It draws warm air from inside an electrical cabinet and expels it through the fan assembly, helping remove heat generated by power supplies, variable frequency drives, contactors, relays and other electrical equipment.
Featuring a 120 V AC, 50/60 Hz supply, a robust Size 4 enclosure grille, an easily replaceable filter mat and IP54 / UL Type 12 protection when correctly installed, the Finder 7F.21.8.120.4400 provides a practical solution for thermal management in industrial automation panels. Its snap-in mounting system helps reduce installation time, while its grey RAL 7035 finish complements standard industrial electrical enclosures.
Key Advantages
- Reverse flow exhaust operation removes warm air from industrial electrical cabinets.
- 400 m³/h nominal free-air airflow at 50 Hz provides high-volume ventilation for demanding enclosure applications.
- 445 m³/h free-air airflow at 60 Hz supports installations operating at the higher supply frequency.
- 120 V AC supply for compatible industrial electrical systems.
- 50/60 Hz compatibility provides flexibility across different AC supply arrangements.
- IP54 protection rating helps protect the enclosure against dust and splashing water when correctly installed.
- UL Type 12 enclosure protection supports use in suitable indoor industrial environments.
- Integrated replaceable filter mat supports straightforward maintenance.
- Size 4 construction provides a substantial airflow capacity within a standardised enclosure opening.
- Snap-in mounting helps simplify installation in prepared cabinet cut-outs.
- RAL 7035 grey finish matches common industrial control panel colours.
- Low-profile external grille design supports neat enclosure integration.
- Reduced installation and maintenance time through the modular fan and filter construction.
- Compatible with Finder 7F Series exhaust filters for planned cabinet ventilation arrangements.
- Suitable for industrial automation, electrical distribution and machinery control panels.
Key Features
- Finder 7F Series industrial enclosure ventilation fan.
- Type 7F.21 reverse flow filter fan.
- Exhaust airflow configuration for extracting warm air from electrical cabinets.
- 120 V AC nominal operating voltage.
- 50/60 Hz supply frequency.
- 400 m³/h free-air volume at 50 Hz.
- 445 m³/h free-air volume at 60 Hz.
- Approximately 270 m³/h system airflow at 50 Hz with a corresponding exhaust filter installed.
- Approximately 300 m³/h system airflow at 60 Hz with a corresponding exhaust filter installed.
- Size 4 fan and grille assembly.
- 255 × 255 mm front grille dimensions.
- 223 × 223 mm nominal enclosure cut-out, subject to the manufacturer's installation tolerances.
- IP54 enclosure protection rating.
- UL Type 12 protection classification.
- Grey RAL 7035 housing.
- Replaceable synthetic filter mat.
- Snap-in panel mounting arrangement.
- Push-in electrical connection system.
- Approximately 72 dB(A) acoustic noise level.
- Approximately 50,000-hour fan service life at 40 °C under the manufacturer's specified conditions.
- Designed for indoor industrial electrical enclosures.
Technical Specifications
- Manufacturer: Finder
- Series: 7F Series
- Model: 7F.21.8.120.4400
- Product type: Industrial enclosure filter fan
- Fan type: Reverse flow / exhaust filter fan
- Installation environment: Indoor electrical cabinets and control enclosures
- Airflow direction: From inside the enclosure to the outside
- Nominal supply voltage: 120 V AC
- Supply type: Alternating current
- Rated supply frequency: 50/60 Hz
- Nominal free-air airflow at 50 Hz: 400 m³/h
- Nominal free-air airflow at 60 Hz: 445 m³/h
- Approximate airflow with corresponding exhaust filter at 50 Hz: 270 m³/h
- Approximate airflow with corresponding exhaust filter at 60 Hz: 300 m³/h
- Fan quantity: 1
- Fan size: Size 4
- Front grille width: 255 mm
- Front grille height: 255 mm
- Overall assembly depth: Approximately 144 mm
- Nominal enclosure cut-out: 223 × 223 mm
- Cut-out tolerance: Refer to Finder's Size 4 mounting drawing
- Acoustic noise level: Approximately 72 dB(A)
- Fan service life: Approximately 50,000 hours at 40 °C under specified operating conditions
- Protection rating: IP54 when correctly installed
- Enclosure protection classification: UL Type 12
- Mounting method: Snap-in panel mounting
- Electrical connection: Push-in terminals
- Housing colour: Grey
- RAL colour code: RAL 7035
- Filter element: Replaceable filter mat
- Compatible replacement filter mat: Finder 07F.45
- Compatible Size 4 exhaust filter: Finder 7F.02.0.000.4000
- Airflow arrangement: Reverse flow exhaust
- Mounting location: Electrical enclosure sidewall or other manufacturer-approved panel position
- Country of manufacture: Italy
Reverse Flow Exhaust Ventilation for Industrial Electrical Enclosures
The Finder 7F.21.8.120.4400 is designed to improve ventilation in electrical enclosures by actively extracting heated air. Electrical equipment such as variable speed drives, transformers, power supplies, contactors and electronic control modules generates heat during operation. If this heat cannot escape, internal cabinet temperatures may rise and adversely affect component reliability.
The reverse flow design of the 7F.21 Series addresses this issue by moving air from the enclosure interior towards the outside environment. This makes the fan suitable for installations where an active exhaust arrangement is preferred, rather than a conventional filtered intake fan.
With a nominal free-air capacity of 400 m³/h at 50 Hz, the Finder 7F.21.8.120.4400 is designed for electrical cabinets requiring substantial airflow. At 60 Hz, its nominal free-air volume increases to approximately 445 m³/h.
Actual installed airflow will normally be lower than the free-air rating because filters, cabinet openings, internal equipment and other restrictions create resistance to airflow. Finder's published performance data indicates approximately 270 m³/h at 50 Hz and 300 m³/h at 60 Hz for a corresponding filtered enclosure ventilation arrangement.
For effective cabinet cooling, the fan should be installed as part of a properly designed ventilation system with a suitable make-up air opening or complementary filter assembly. The positioning of the inlet and outlet should encourage airflow across heat-generating equipment rather than allowing air to bypass critical components.
The Finder 7F.21.8.120.4400 offers a high-volume ventilation solution for electrical panels containing components with significant heat dissipation. By promoting continuous air exchange, the fan can help reduce temperature build-up when the surrounding air is cooler than the air inside the enclosure.
The correct ventilation capacity depends on several factors, including the total heat dissipated by the installed equipment, the permitted internal cabinet temperature, the ambient temperature and the resistance created by filters and cabinet construction.
Airflow selection should be based on installed operating conditions rather than the free-air rating alone. A ventilation fan cannot cool an enclosure below the temperature of the incoming ambient air. Where ambient conditions are unsuitable or heat loads are excessive, an enclosure air conditioner or another cooling method may be necessary.
The fan's approximately 72 dB(A) noise level should also be considered during system design, particularly where electrical cabinets are installed close to occupied work areas. This is a high-airflow industrial ventilation device intended for applications where thermal performance is a primary requirement.
Replaceable Filter Mat and Reduced Maintenance Time
The Finder 7F.21.8.120.4400 incorporates a replaceable filter mat that can be serviced as part of routine enclosure maintenance. The filter helps manage airborne contaminants in the ventilation path and supports the protection of sensitive electrical equipment.
For this Size 4 fan, the corresponding replacement filter mat is the Finder 07F.45. Using the correctly specified filter material helps maintain the intended fit, airflow characteristics and enclosure protection performance.
Filter condition has a direct effect on ventilation performance. As airborne dust accumulates, the resistance to airflow increases, potentially reducing cooling effectiveness. Inspection and replacement intervals should therefore be based on the surrounding environment and the manufacturer's maintenance recommendations.
The fan's snap-in mounting arrangement and accessible filter construction are designed to reduce installation and servicing time. Maintenance should only be performed after following the relevant electrical isolation and safe working procedures.
Size 4 Snap-In Mounting and IP54 Enclosure Protection
The Finder 7F.21.8.120.4400 uses a Size 4 mounting format with an external grille measuring approximately 255 × 255 mm. It is designed for installation into a nominal 223 × 223 mm enclosure cut-out, with the exact cutting dimensions and tolerances specified in Finder's installation documentation.
The snap-in mounting system helps simplify installation into a prepared electrical enclosure panel. Push-in electrical terminals support efficient connection to the appropriate 120 V AC supply.
When installed according to the manufacturer's instructions, the assembly provides IP54 protection and is associated with a UL Type 12 enclosure protection classification. These ratings are relevant to protection against dust and water ingress, but they depend on correct installation and the overall enclosure design.
The RAL 7035 grey finish complements commonly used industrial cabinet colours, making the fan suitable for integration into standard electrical distribution and automation enclosures.
The Finder 7F.21.8.120.4400 is intended for indoor industrial enclosure ventilation. It should not be assumed suitable for outdoor exposure or aggressive environments without verifying the complete installation's environmental requirements.
Typical Applications
- Industrial electrical cabinet exhaust ventilation.
- Automation and PLC control panel cooling.
- Electrical switchboard thermal management.
- Variable frequency drive and motor control enclosures.
- Industrial machinery electrical cabinets.
- Manufacturing and production line control panels.
- Power supply and transformer enclosure ventilation.
- Electrical distribution equipment cooling.
- Industrial process control cabinets.
- Packaging and processing machinery enclosures.
- Machine tool electrical panels.
- Industrial OEM electrical cabinet manufacturing.
- Facilities maintenance and electrical enclosure refurbishment.
- High-airflow cabinet ventilation systems using 120 V AC supplies.
- Applications requiring a reverse flow exhaust fan rather than a standard intake fan.
