Wire Gauge on 3-Wire Fan Does Not Match Data Sheet

One common item that is brought up to the technical department is that a customer will order a 3 wire fan and the wire leads are a smaller gauge wire than the data sheet stats. For this example I will look Digi-Key part numbers P15633-ND and P14517-ND. This would be NMB Technologies 2-wire fan 2410ML-04W-B60-B00 and 3-wire fan 2410ML-04W-B69-B00. Now if you were to look at the Datasheet for these two fans you will notice that the lead wire is listed as 24 AWG in Red (+) and Black (-). You will also notice this is the same data sheet for both part numbers. In this example we are fortunate to have a separate drawing for part P14517-ND. If you look closely at page 3 of the drawing you will notice note 4, 5, 6 on the wires. This is calling out a wire gauge of 26 AWG and colors Red (+), Black (-), and White (s). This smaller wire gauge is done to allow room for the additional wires.

Note: There are times the additional wires are not shown in the data sheet or manufacturer drawing and not every 3-wire fan has smaller wires then the 2 wire fan. It is a common occurrence to allow the wires from a 3 or 4 wire fan to fit through the same grommets and housings as the same 2 wire fan.