In the fields of industrial automation, power electronics, and process control, a large number of heating elements are integrated inside control cabinets, distribution cabinets, and servo drive cabinets - from PLCs and frequency converters to servo drives and power modules. The reliable operation of these components is highly dependent on the stable control of the internal temperature of the cabinet. Research has shown that the failure rate of electronic devices is exponentially related to their operating temperature, and for every 10 ° C increase in temperature, their lifespan may be reduced by half. Therefore, cabinet thermal management is not an optional auxiliary project, but a core link to ensure the long-term stable operation of the entire automation system.
The Rittal SK 3241.700 Blue e+fan filter unit is a high-performance solution to address this challenge. As a leading global supplier of cabinet technology, Rittal's Blue e+series represents the direction of high efficiency, energy efficiency, and intelligent thermal management. The SK 3241.700 model is an ideal choice for cooling many industrial cabinets due to its balanced airflow, excellent protection level, and convenient maintenance design.
Product positioning and design philosophy
SK 3241.700 is a wall mounted fan filter unit belonging to the Rittal Blue e+product series. The original intention of its design is to provide efficient and controllable air convection heat dissipation for enclosed cabinets without sacrificing the cabinet protection level (IP/NEMA). This unit adopts a tool free assembly design, which can be quickly fixed to the opening of the cabinet wall panel through optimized retaining hooks, significantly reducing on-site installation time.
Its shell is made of plastic and its color is RAL 7035 (light gray). This industrial standard color not only matches the appearance of most control cabinets, but also has good weather resistance and anti-aging performance. The delivery status of the entire machine includes pleated filters, which can be installed and used directly by the user after opening the box, without the need to purchase additional filter media.
Core Technology: Advantages of Diagonal Fan Technology
The core feature that distinguishes SK 3241.700 from traditional axial or centrifugal fans is the use of diagonal fan technology.
1. Working principle and performance characteristics
The diagonal fan combines the high airflow characteristics of axial fans and the high static pressure characteristics of centrifugal fans. Its blade design allows airflow to enter along the axis of the fan, accelerate through the impeller, and flow out in a diagonal direction (i.e. at a certain angle to the axis). This design brings two significant advantages:
Superior pressure stability: In actual cabinets, fan outlets often face resistance from filters, heat dissipation components, and internal cables. Under high back pressure conditions, diagonal fans experience much less airflow attenuation than traditional axial fans, ensuring sufficient airflow even under real working conditions.
More even and constant ventilation inside the cabinet: The diagonal fan has higher directionality and diffusion angle in the air outlet direction, which can effectively deliver cold air to the hot areas deep in the cabinet, avoiding the formation of local eddies and dead corners, thereby achieving a more balanced overall heat dissipation effect.
2. Motor and electrical parameters
SK 3241.700 adopts a shaded pole motor with an outer rotor, which is a mature technology widely used in industrial fans. It has the characteristics of simple structure, high reliability, and low electromagnetic interference. The electrical parameters are as follows:
Rated operating voltage: 230 V, 1~, 50 Hz/60 Hz (globally applicable voltage design).
Power consumption (Pel): 43.2 W at 50 Hz and 54.5 W at 60 Hz. Compared to the airflow efficiency it provides, this is a very economical set of energy consumption data.
Rated current (maximum): 0.27 A at 50 Hz and 0.32 A at 60 Hz. The low starting and operating currents reduce the burden on the cabinet distribution circuit, and the front-end pre fuse only needs to be equipped with a 4A miniature circuit breaker.
In depth analysis of air volume performance
When choosing a fan filter unit, air volume is the primary performance indicator to consider. SK 3241.700 provides multiple sets of measured air volume data under different configurations, which is crucial for engineers to perform accurate thermal calculations.
1. Comparison of air volume under different filter media
Unstoppable airflow (free air outlet):
Equipped with pleated filter (factory standard): 272 m ³/h at 50 Hz and 280 m ³/h at 60 Hz.
Equipped with chopped fiber filter: 225 m ³/h at 50 Hz and 245 m ³/h at 60 Hz.
Used in combination with the outlet filter:
Equipped with pleated filters: 242 m ³/h at 50 Hz and 246 m ³/h at 60 Hz.
Equipped with a broken fiber filter: 173 m ³/h at 50 Hz and 187 m ³/h at 60 Hz.