KD250A H.55
Physical Properties
design type axialfan
air supply 3200 m³/h
pressure pt 220 Pa
speed controllable yes
impeller axial
size 400 mm
Installation site
machine or wall
mounting Built-in fan and Built-on fan
air direction at order
reversible with restrictions
Thermokontakt possible
possible temperature at nominal current -20 °C bis 60 °C
air supplyNenn 2000 m³/h
rotation speedNenn 2800 U/min
Electrical Properties
  Three-phase motor
voltage 400 V
frequency 50 Hz
other voltages 400V-50Hz, 480V- 60Hz, 500V-50Hz
Imax 0,65 A
protection class IP 44 to IP 54
other Protection classes IP x6
heat class F and H
star / delta connection yes
Material properties
material steel ring
surface Galvanized or powder-coated
impeller komponend plastic
stainless steel (V2A , V4A) possible
offshore modell possible
Property- Tests
climate chamber test yes  (design test)
salt water test yes  (design test)
protection class test: IPx6 yes  (design test)

All details [ liability-free ]


Please get further data from the data sheet:
Axialfan KD252


The axial fan is also deliverable into high-grade steel and for the offshore use at a corresponding execution, see high-grade steel ventilators and offshore ventilators.

built-on ventilator
available from stock

built-in ventilator
available from stock

plate ventilator
available from 50 pieces


Description of axial fan KD252

The axial fan type KD252 is a three-phase fan with a rated voltage of 400 volts, 50Hz. Due to the speed of 2800 rpm, high performance can be achieved here with a compact design. The impeller of the fan has a nominal diameter of 250mm. The nominal size is 250mm.

The fan can be used in a wide variety of applications, including cooling of generators, containers, machinery, cooling of castings or forgings. The fan is very well applicable as axial built-in fan in hall walls, office walls or walls in sandwich construction for example for machine cooling in containers.

Voltage and control of the axial fan KD252

The fan is equipped as standard with thermal contacts in the form of bimetal switches in the winding, to protect the motor.

The voltage of the motor in three-phase operation is 400Volt, 50Hz as standard. However, special voltages of 480Volt, 60Hz (USA) and 575Volt, 60Hz (Canada) are also possible. Special voltages of 500Volt, 50Hz can also be manufactured on short notice.

Stainless steel versions of the KD252 axial fan

In the beverage and food industry (food industry) stainless steel fans in V2A (material number 1.4301 or AISI 304 or X5CrNi189) are used. The axial fan KD252 is also available in stainless steel. We produce the motors from high quality aluminum castings, which can be left raw for the food industry but also painted with food color. It is also possible to cast the motor from aluminum material approved for the food industry, for annually recurring purchase quantities.

In coastal areas or on drilling platforms, the so-called offshore area, where the air is very salty, fans made of stainless steel V4A (material number 1.4571 or AISI 316 or X10CrNiMoTil810) are used. In addition, the use of salt water resistant paint can be used as a paint finish.

Material of the axial fan KD252

Depending on the application, the axial impellers are available in glass fiber reinforced plastic, or aluminum impellers for high temperatures.

The rectangular plate design in the form of a plate fan is available. Here, however, there is a need for a minimum order quantity for cost reasons.

The IP44 protection class is standard. If protection class IP54 and protection class IP56 are required when ordering, these can also be supplied.

The various mounting positions and corresponding air directions can be viewed in the Service section or in the technical documentation. These should be specified when ordering, but can also be changed afterwards.

Technical illustration of the axial fan KD252

The fan KD252 can be used in reversing mode. This means that the air direction can be reversed. The only thing to note is that the impeller blades are profiled for optimum efficiency, in the reversed direction the air flow is reduced by about 15%.
The motors are specially designed and developed for the axial fans by Kaiser Ventilatorenbau. According to DIN EN 60085 the thermal protection class is F or on request H.
Type tests are available, which show the storage temperature and the temperatures possible for operation.
For the use of the stainless steel fans, salt water tests for the offshore area and an IPx6 humidity test are available, which confirms the usability.
The fan carries the CE mark according to the Ecodesign Directive ERP2015 (ErP Directive 2009/125/EC EU Regulation No. 327/2011). and the Machinery Directive.
In modulating operation, the fan can be adjusted over the entire speed and power range. In the simplest case, this is possible by means of robust multistage speed controllers in transformer design.
Control and the use of frequency converters is possible. According to DIN-IEC/TS 60034-17 it has to be considered that depending on the frequency converter an all-pole sine filter has to be connected between motor and fan.
Various add-on parts and supplements in the form of discharge protection grilles and weather protection flaps can be ordered in order to also comply with the Machinery Directive.
Ready-made CAD data in STEP format is available for download. The fan can thus be taken into account at an early stage in the design process to save costs and time.

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