for a project I want to apply two 120 mm 12V fans (not for computer cooling). The ones I got have only two wires and work always on full speed (about 90 cfm). The full speed is not enough for me, so I looked for fans with about 150 cfm (at full speed). All I found have three or four wires (eg. this one http://www.frozencpu.com/products/12944/fan-858/Sunon_120mm_x_25mm_Precision_Ball_Bearing_Fan_-1500_CFM_PMD1212PTB1-A.html?tl=g36c435s1106
). Since I have already done the wiring and don't want to change, I wonder if I could use such fans (my Arduino only controls, wether the fans will run or not, i.e. wether they get power or not). At the end of my wiring solution I added a box for the remaining wires. If necessary I could add some electronics inside to make the fans running at full speed, but if possible I want to avoid to send control signals through the third or third and fourth wire.
Can anyone help me solving my problem?