fan rpm question

P

PG~LID

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Mar 15, 2001

• Apr 6, 2001

• #1

just wondering on how if a fan is a 2 wire set up...how do programs like mbm5.0 and others know the rpm's of the fans?....there are only 2 wires....i can see how a 3 wire hook up could send a reading through the third wire...but when you only have 2????? just wondering.

 

OP

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PG~LID

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Mar 15, 2001

• Apr 6, 2001

• Thread Starter
• #2

bump

 

D

Daniel ~

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Dec 16, 2000

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Seattle Wa.

• Apr 6, 2001

• #3

Moved post to "Cooling"

 

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doublec16

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Apr 3, 2001

• Apr 6, 2001

• #4

If the fan is supplied with a constant voltage through 2 wires, the rotation speed is related to how much current the fan draws, which would be measured through those same 2 wires.

 

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Gerti

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Feb 18, 2001

• Apr 7, 2001

• #5

The third usually yellow wire measures the RPM's of the fan.If u remove it or u have a two wire fan than say bye bye to monitoring the RPM's.