Reliable Data - Documentation and Fan Selection

Selection of the right fan on the basis of an application- specific operating point is only possible with reliable data and is generally performed with the aid of appropriate product selection software.

The properties of ebm-papst fans are documented in product data sheets and printed catalogues (Fig. 1-2) as well as in our product selection program, the Product Selector. At ebm-papst, the origin of the fan performance data contained in the software can always be traced back to measurements (as described in our article on Precision Measurement). The required air flow and the static pressure increase which the fan subsequently has to achieve in practical use are the minimum criteria employed for the selection process.

Optimised software

Fan curves Plug Fan
Fig. 2: Catalogue characteristic curves (source: RadiPac catalogue)

Because the required operating points are not always identical to the measured operating points, there is a need for interpolation between the measured values. Therefore familiar affinity laws for flow machines are often used. These are sufficiently accurate in cases where fans merely consist of a flow machine, in other words an impeller. ebm-papst EC fans however are a complete system, and therefore also include a motor and control electronics. These two assemblies do not conform to the fan affinity laws, but rather exhibit completely different performance characteristics, particularly in the partial load range. The selection software has been appropriately optimised to obtain a highly accurate forecast of the operating behaviour of the fan unit at any conceivable operating point.

Product Selector

ebm-papst’s Product Selector software provides a particularly user-friendly means of finding the right fan. The selection program makes it possible to check fans at various operating points and determine the performance data. It additionally permits dynamic comparisons closely resembling actual operating conditions.

The influence of temperature, altitude and installation space can also be incorporated. If there are several fans in the specified performance range, the aerodynamic and acoustic data displayed can be used to help select the most suitable model. Another option available is calculation of the life cycle costs for the fans selected. The performance data are also output at the specified operating point with suction and pressure side sound power level values over the octave band. The software can be incorporated into customer device configuration programs by way of a DLL interface.

Certified accuracy

Fig. 4: Validation test on a total of 38 different fan models from ebm-papst. Shown here: K3G310-AX69-01. Red dots (1–15): Selected operating points for measuring actual power consumption

The performance data output is extremely accurate, as confirmed by the inspection authorities (TÜV Süd). Validation measurements performed on all 38 models in the RadiPac product range show that on average the efficiency level indicated by the Product Selector even tends to be slightly too low.

What procedure was employed for the validation measurements? 15 reference points were chosen for each fan in the RadiPac product range. These were measured on the certified chamber test rig and the performance data was then compared to the data from the Product Selector (Fig. 4).

Fig. 5: In reality, fans from ebm-papst tend to have a higher efficiency level than shown in the product documentation.

The test revealed that the calculated values from the Product Selector are almost identical to the values actually measured. In accordance with AHU guideline 01, the best possible accuracy class 0 is thus obtained for RadiPac fans (Fig. 5, Accuracy classes according to AHU guideline 01, 2013, German association of air handling unit manufacturers, based on DIN 24166)). In other words, ebm-papst RadiPac fans in as-delivered condition tend to exhibit a higher level of efficiency than that indicated by the Product Selector. This guarantees true planning reliability for customers.

All customers can download the ebm-papst Product Selector software by registering on our document server, ds.ebmpapst.com.au.