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|kbn| · 03-10-2004, 11:11 AM

Ususally lower voltage would increase the resistance though, would this happen on fans?
Anyway the fan has arrived and ive got some numbers for you. I only have a multimeter, not a scope or anything, so the peak startup current wont be exact, as multimeters measure RMS values. Instead it will be RMS over the first second.

Startup 12v = 0.63A
running 12v = 0.17A

This looks about right, The fan is rated for 0.55A at 24v on the label, if thats start up or running current I dont know. I was expecting 1A running at 5A startup with what you said about it almost doubling the current draw!
Should definatly work on well on my pc's ATX psu without problems.
The fan doesnt start a 5v, which is what I expected. At 7v it wants to move, but cant. If i push the fan round and leave it spinning at 7v it will continue slowley for a while. I will try 9v later, either using a linear regulator if i can find it, or 12v-3v mod from the psu.

03-10-2004, 11:11 AM	#23
\|kbn\| Cooling Savant Join Date: Feb 2004 Location: W. Sussex, UK Posts: 329	Ususally lower voltage would increase the resistance though, would this happen on fans? Anyway the fan has arrived and ive got some numbers for you. I only have a multimeter, not a scope or anything, so the peak startup current wont be exact, as multimeters measure RMS values. Instead it will be RMS over the first second. Startup 12v = 0.63A running 12v = 0.17A This looks about right, The fan is rated for 0.55A at 24v on the label, if thats start up or running current I dont know. I was expecting 1A running at 5A startup with what you said about it almost doubling the current draw! Should definatly work on well on my pc's ATX psu without problems. The fan doesnt start a 5v, which is what I expected. At 7v it wants to move, but cant. If i push the fan round and leave it spinning at 7v it will continue slowley for a while. I will try 9v later, either using a linear regulator if i can find it, or 12v-3v mod from the psu. Last edited by \|kbn\|; 03-10-2004 at 11:49 AM.