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Unread 11-05-2002, 04:20 AM   #23
gmat
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Join Date: Mar 2001
Location: France
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Quote:
Originally posted by MadDogMe
Does'nt that allow them to run slower as well?(the Hall thingy?), gives them a lower stalling speed?. I read somewhere that it did, feeding the current in pulses or something?, whatever!, Hall was mentioned...
Not at all
It's the standard probe you have on 99% of fans - it's the little device that detects fan rotation. When the fan is spinning, it emits a pulse wave (maybe thats what you heard), each pulse is in sync with 1 blade (more precisely, rotor coil) passing by the probe. i.e. 1 pulse=1 spin...
You can hook the wire to Maxim chip, put the fan alim on the chip as well, and the chip will control the fan speed with great precision (yes you can slow it down...) - the chip i was referencing to is a multiple-fan control. Found it while browsing Maxim's catalog.
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