Preen resources for air conditioner testing
A changing climate, with ever-increasing extreme temperatures, and a high degree of urbanisation have driven the demand for air conditioning units, particularly in recent years, even in regions where the need was virtually non-existent in previous decades. In view of these developments, therefore, how to reduce the energy consumption of HVAC (Heating - Ventilation - Air Conditioning) systems has become a key factor in the design phase, not only for domestic air conditioners. An important tool for verifying HVAC in terms of cooling and heating efficiency of air conditioning units under various ambient conditions is, among others, the psychrometric calorimeter or air enthalpy measuring device.
Air conditioning equipment generally refers to equipment that is used to create and maintain constant conditions of temperature, relative humidity, and indoor air movement and purity. Calorimetric chamber measurements and enthalpy measurements (in which case the air conditioner under test may be installed in a conventional manner in a cooled/heated room) are the two main methods of testing air conditioning equipment. Depending on its type, different standards are then used for the test setup, for example ISO 5151, ISO 13253, ISO 15042, GB/T 7725, GB 21455, ARI-310/380, JIS B 8515 and JIS C 9612.
For both of these measurement methods, a stable AC current source with a guaranteed "clean" sinusoidal waveform of sufficient power is necessary. Preen 's power supplies offer just such a stable and clean output for testing air conditioning systems while ensuring compliance testing according to ISO 5151. It is also a cost-effective solution where the customer does not pay unnecessarily for functionalities that are not needed in this case (e.g. arbitrary shaping of the output signal waveform, etc.).
For example, the AFV+ series provides a stable and clean sine wave output with THD ≤0.5%, helping to eliminate network interference, which ultimately increases the required accuracy of test results. In some cases, the power quality of the device under test can even help suppress interference from DUT interference to the connected local electrical system and surrounding equipment.
According to ISO 5151, the air conditioning system must be tested at 90% and 110% of rated power during the maximum operating cooling/heating test. If the air-conditioning system has more than one input voltage, it shall be tested at 90 % and 110 % of the defined nominal voltage. Of course, if the DUT has different input nominal frequencies, these variations must also be tested.
But the Preen brand offers more - the AFV+, AFV, AFC and AFV-P series programmable power supplies are solutions for many other applications. These power supplies provide an adjustable output voltage range of 0-310 VAC and an output frequency range extensible up to 2000 Hz. With a power range from 600 VA to 2000 kVA, they are thus naturally suitable not only for testing air conditioning units, but wherever a stable AC power supply with a precisely defined waveform is required. And all this at a very reasonable price.
