# Result Charts - Fans and Compressors

A typical fan chart is shown below: Figure 1: Fan or Compressor Chart The upper chart shows the fan performance curve (blue), and the duty point (shown by the larger yellow triangle), the operating limits of the fan as specified in the database (the crosses X on the performance curve) and the efficiency curve (red). The duty point on the efficiency curve is also shown (smaller yellow triangle in the upper chart). The lower chart shows the power (purple) curve, together with the duty point. Fan charts provide invaluable information that should be utilized when considering your system designs. For example, we need to consider if the fan is being operated near to the best efficiency point (BEP). The BEP occurs at the maximum height of the efficiency curve. Efficient designs should have duty points as near as possible to the BEP.