How Many Fans in Your System Unit

[Anusha]

Must learn my electronics well!these studies keep me away frm them..

Yeah....
Don't they have Electronics as a technical subject for O/Ls anymore?

 

[zCexVe]

Thats gr8 Electronics..those idiots only knw to translate english words into sinhala..
There rnt not much enthusiasts like us to learn..
u knw what they call step down tranformers..
"Avakara parinaamaka"
I told them a word starting frm "Ava.. Pa..."too..

 

[shanX]

 

[Anusha]

But they can't help it. There weren't (aren't) disctinctive terms for those electronics stuff in English.

 

[zCexVe]

oh u knw what they teach for GIT in O\Ls..
this is the 15th MCQ of there paper frm ma school
15th
How much data can a cd hold up?
I asked what CD(22 mins or 80 mins)no answer..
35th
How much data can a cd hold up as a multiplier of Floppys'data
7(00/1.44=486)

34th
What is the maximum FSB in a mobo now?
correct ans was 800Mhz..
fortunately i got the paper b4 print and corrected it to Intel and 1066Mhz.Then the Q was removed coz teachers dont knw about that..
19th
In what gazzette that says about pirating CDs/Softwares illegal?
ans is 14th of 1995 I think..

Remember all these r in Sinhala..

 

[zCexVe]

there r more funny things like that..I dont hav the paper with me right now.If then we would laugh for a month..If i can i'll post the paper i made for taking members into ma club..[I'm the secretary thats why]

 

[Anusha]

What is GIT? I don't know anything about the new syllabus.

 

[Anusha]

Just wanted to highlight a point. The maximum FSB in a desktop CPU up to now is 266MHz.

 

[pasanlaksiri]

Automatically means, thermally adjusted fans? Yeah you can do that

Automatic Temperature Control Fan When System is cool ( ucan adjust temp ) fans r automatically goes off mode.

 

[Anusha]

Automatic Temperature Control Fan When System is cool ( ucan adjust temp ) fans r automatically goes off mode.

Hey, we had already figured it out before you answered

 

[pasanlaksiri]

Ultra Simple Cricuit for Automatic Fans
Very very Low cost Circuit

This is the actual size of the circuit

"This circuit was designed to automatically activate a set of three or four small DC fans to cool a large cool-rib for a 10 Amp powersupply. Can be used in a variety of other applications as well."

Couple Notes:
Th1, the 50K thermistor, is a standard type. Mine was a bar or rectangular looking thingy. Available from Tandy/Radio-Shack. Almost any type will do. I experimented with different models from 22K to 100K and all worked fine after replacing the trimmer pot.
The one used in the above circuit diagram was a 50K model made by Fenwal (#197-503LAG-A01). This 50K was measured at exactly 25 °C and with 10% tolerance. The resistance increases as the surrounding temperature decreases. Tolerance for my application (cooling a large powersupply coolrib) is 10%. Another name for this thing is 'NTC'. NTC stands for "Negative Temperature Coefficient" which means when the surrounding temperature decreases the resistance of this thermistor will increase. You may have to shop around to get the cheapest price. Some thermistors can be had for as little as $4.00 but as much as $55.00 Canadian currency for the glass encapsulated type (the best).
I replaced my thermistor for a 60K hermetically sealed glass type since the environment for my application may contain corrosive particles which may affect performance on a future date.

P1 is a regular Bourns trimmer potentiometer and adjusts a wide range of temperatures for this circuit. I used the 10-turn type for a bit finer adjustment but the regular type may work for your application.

R1 is a 'security' resistor just in case the trimmer pot P1 is adjusted all the way to '0' ohms. At which time the thermistor would get the full 12 volt and it will get so hot that it puts blisters on your fingers...
R3 feeds a bit of hysteresis back into the op-amp to eliminate relay 'chatter' when the temperature of the thermistor reaches its threshold point. Depending on your application and the type you use for Q1 and Re1, start with 330K or so and adjust its value downwards until your satisfied. The value of 150K shown in the diagram worked for me. Decreasing the value of R2 means more hysteresis, just don't use more then necessary. Or temporarily use a trimmer pot and read off the value. 120K worked for me.

Transistor Q1 can be a 2N2222(A), 2N3904, NTE123A, ECG123A, etc. Not critical at all. It acts only as a switch for the relay so almost any type will work, as long as it can provide the current needed to activate the relay's coil.

D1, the 1N4148, acts as a spark arrestor when the contacts of the relay open and eliminates false triggering. For my application the 1N4148 was good enough since the tiny relay I used was only 1 amp. However, you can use a large variety of diodes here, my next choice would be a regular purpose 1N4001 or something and should be used if your relay type can handle more then 1 amp.

If you like to make your own pcb, try the one below. The pcb is fitted with holes for the relay but may not fit your particular relay. It was designed for a Aromat HB1-DC12V type. The variety and model of relays is just to great. How to mount it then? Well, I left ample space on the pcb to mount your relay. You can even mount it up-side-down and connect the wires individually. Use Silicon glue, cyanoacrylate ester (crazy glue), or double-sided tape to hold the relay in place. Works well. Note that the pcb and layout is not according to the circuit diagram in regards to the hookup of the fans. The PCB measures approximately 1.5 x 3 inches (4.8 x 7.6mm)
If you print the pcb to an inkjet printer it is probably not to scale. Try to fit a 8-pin ic socket on the printed copy to make sure it fits before making the pcb...

More Info Go Here >>>

http://www.uoguelph.ca/~antoon/circ/auto-fan.html

 

[Anusha]

That circuit is simple, yeash, but it will drive zCexVe away to retail stuff. The ones I gave were much, much simpler.

 

[pasanlaksiri]

That circuit is simple, yeash, but it will drive zCexVe away to retail stuff. The ones I gave were much, much simpler.

Yep. Mmmm balamu hadala

 

[Anusha]

Yep. Mmmm balamu hadala

Balamu balamu.

 

[zCexVe]

Hadala balanna oya keli hoyaganna eka thama prashne.Athe sallith ne me davasvala...

 

[Anusha]

Hadala balanna oya keli hoyaganna eka thama prashne.Athe sallith ne me davasvala...

Those parts are easy to find, and cheap!

 

[pasanlaksiri]

Those parts are easy to find, and cheap!

Do u have 100 bucks ( less than 100 ) ? Ah its enoughf to make that Anusha's CCT

 

[themera]

i have 4 fans i fink

 

[dunits]

only 2

 

[dpg]

only 2

Ube eke 3k thiyenawane...


power supply unit eke hari video card eke fan eka amathaka wunada?