Maximum PC

I have three of the fans below... they are rated @ 2.5amps and 240cfm and i need a fan controller that will handle them. prefferably nothing fancy, i just need some knobs and no temp sensors or indicators of any kind. so the fan controller would need to handle 8-10amps between the three. does anyone know of any that would handle this? I havent been able to find any. hopefully im not stuck building one but if i have to i will. Im open for suggestions. The reason I say simple is because i dont necessarily want a drive bay controller setup. just something that will fit inside the case. i'd prefer one knob to control all three but ill take what i can get. thanks in advance for the help.

http://www.newegg.com/Product/Product.a ... 6835213001

wow, no one have any ideas??

With the modern BIOS and fans, we no longer need to use separate controllers. You can plug fans into your motherboard now and expect them to be controlled automatically very well.

The fans I'm reading that you have are excessive so I'd rather talk about them. 8-10Amp for the trio? 240CFM a piece is pretty wild, ya gotta admit. A pair of 75 CFM 120's cool my entire rig, and even blow that evil hot air into the case after the radiator. If I can't talk you out of those hurricane force fans, then you're left with making your own. This is why there are no replies...it's very non-typical.

well, to be honest this is going to be used as an inline fan booster for the AC vents in my car. but...since they are technically a computer case fan i figured some gurus here would have a nice "how to" idea.

Well, hell's bells, how come we didn't see that?????

Lamptron's fan controllers will do 20 to 100 watts per channel, for all three on a single channel you will need >90 watts on that channel to run them full speed.

http://www.performance-pcs.com/catalog/ ... ter_id=137

hey... i checked out the link and didnt see a single controller that went up to 90 watts. the only ones that will are switches and not variable speed controllers.

Do you need all of the fans on one channel? it can be 1 channel / fan with those controllers having multiple channels.





Ted

The biggest problem you are looking at is the current draw of the fans. Unlike typical PC fans that draw a few hundred mA you have fans that draw about 2.5 Amps at full speed. There are likely some commercial PWM (Pulse Width Modulation) circuits out there that would do the job. Another option would be to build a PWM fan speed controller similar to this one but rather than use a transistor to drive the fan(s) replace the transistor with a MOSFET. Allow the circuit to drive 3 MOSFETS to handle the 3 fans rather than a single MOSFET. It would be a home brew project.

Just My Take
Ron

And then we get into a technical automotive topic really. Are you planning to just do this for more air conditioning, or thinking of cooling an amp rack or something like that? The A/C in your car puts out what it puts out (thermal units remain the same no matter what the air velocity is). To boost that will, in effect, have more air but warmer than non-boosted air. I've done something like this a ways back for an amp in the rear because not much A/C got back there, but it still didn't need that type of air output. An 80CFM fan at the end of the run does better than a 200CFM fan up front.

I see what you're saying... the air is only going to get so cold and pulling it away from the evaporator faster might not allow the air to chill long enough. right? If so, I get it. but the AC in my car is an aftermarket one I installed and the air output just sucks. the blower motor is 330cfm total between for 3 vents. driver, center and passenger. my AC vent with a thermometer will get down to 45deg. I honestly dont think if I put an inline fan booster (or two) in a "junction box" at about half length of the ducting that im going to loose much cooling. I just want the air to blow my hair back a little on high like it should and not have to put my face up to the vent.

Actually 45 degrees F isn't all that bad. I won't discourage you from trying what you have in mind. Therefore, forgetting the application and considering the current draw you will either need to find an off the shelf PWM fan speed controller or build one. Your biggest problem is the current these fans draw in comparison to a simple PC fan. You are looking at controlling about 10 amps with a margin in there.

Ron

Yeah; if you get 45F out of vent that's damn good. You sure could get a bit more CFM out of there and maybe rustle your arm hairs; but perhaps not with these beefy fans. I'm going to take a fork from Reload's topic and suggest that there's something mechanically wrong here and may be hard to find without ripping the dash out (I even cringe at that!). 300CFM is fairly typical for a squirrel cage and should be enough for 4 registers.

Let me set up a recent example I found in our home and see if you still follow for the problem I had in mind: Heat kicked butt the first "Winter" here (it gets a nippy 55...ptthh), then it kind of just sucked. Closed registers and our room was sill chilly but the attached bathroom was blowing like mad. So the last two years we close the bedroom register, fully open the bathroom's, open that door to the room, and we're warm...but power bills went through the roof. I climbed up there 2 weeks ago chasing Romex runs and just happened to notice that a duct was not connected...at all. It just happened to be right off the heater and into two bedrooms; which were culprits to begin with. An inspector had been up there, climbed over it, and obviously sat on it to separate it. We've been heating the attic.

See anything to look into? My first would be to see if all ducting is fully connected. Anything 80's and up is many rigid plastic ducts spread about and connected by rubber boots. Take one boot off anywhere and that's where all the air is going to want to go. Not out the register, but perhaps behind the dash. If you can pull the radio unit, that's where a main header usually is. You're getting cold air, just not a lot of it...so the A/C is working. The next would be to think about where the blower is in your car, if you can get to it easily (post-90's, no), and if it's dirty or not. A squirrel cage has a flaw in that just a fine coverage of it's fins can drastically reduce it's output. Our vertical fans in the house need blown out weekly just because we have cats...

Just some things to think about before jumping in with patch jobs. Maybe the blower just needs a little oil. I don't know...I'm waaaaay over here