Many PC fans have a speed sensor in them that tells the CPU how fast the
fan is going. When the fans are plugged into the PC motherboard, the
system runs a closed loop speed control vs temperature to control the
fan speed.
The third wire is in the connector but not used when the mating
connector is going to a fixed 12V source (PC harness supplied. In this
case t he mating side of the connector only has two wires coming out.
The speed sensor is left unconnected. Use the two wires that are
attached to the mating connector. When you have all the parts in front
of you, with the harness supplied, this will be clear I think.
The thermistor fans come with the thermistor attached with its own
separate 2wire line without connector.
The fans will run either direction depending on polarity but, as with
all propeller and fan blade design, there is a most efficient design
direction. There are arrows marked in the sides of the fan for
airflow. Use this direction.
You can still find these on e*(B**Y) for 7-8 depending on the color
etc. but it looks like the single pc price went up a little at
Tiger..now $11.. THink I found them at Mouser or one of the other
distributers also, and they usually have a 10pc break.
I opted to use mine without grilles over them. Grilles make noise as
air passes over them (not really an issue with these) and efficiency is
slightly reduced. I'm just cheap and didn't have any on hand.
eMail with any questions.
Also, please let us know how you like these fans after using them. An
aerospace engineer friend of mine said Silenx used the same software to
design and optimize these fans that the military guys used on submarine
props.
Curt
KU8L
J G wrote:
Hi Curt,
Thanks for sharing the Silenx fan information. I ordered three of the
120mm fans for my 30L-1 amps to replace my current fans (too noisey,
not enough cfm). I haven't tried them yet, and it may be a few days
before I get at that.
A couple questions:
1-- Where are you buying them for $7? Tiger Direct has the 80mm for
$10.99 and they go up from that price.
2-- Your photo #8 shows the connector siliconed to the back panel.
This may seem like an obvious matter as there are only two wires
coming out (three going in). But, those two are the 12v? The other one
is for what? I ask because I bought fan a year or so back, not a
Silenx, that did not have the 3 in/2 out connector ... just a 3 pin
connector for the 3 wires. I guessed incorrectly as to which 2 were
the 12v and smoked (literally) the fan. I don't want to take that
chance with my new Silenx fans! Heck, I even splurged and got the ones
with the LED's! If they are that quiet I will need the visual feedback
(and I like things that light up).
Thanks & 73,
Jim
W9GL
_______________________________________________
Drakelist mailing list
[email protected]
http://mailman.zerobeat.net/mailman/listinfo/drakelist
