DIY Temperature Controlled Case Fan Controller Design

Control: management of fans, temp/rpm monitoring via soft/hardware

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BruceMellen
Posts: 9
Joined: Mon Jun 07, 2010 4:11 pm
Location: Rochester NY

DIY Temperature Controlled Case Fan Controller Design

Post by BruceMellen » Fri Apr 29, 2011 11:21 am

I’m pretty much disappointed in my motherboard’s and case’s ability to keep the case fans as quiet as possible, given my varying room temperature and varying heat being generated. Fan controllers I see seem to be more about bling and constant user attention. Temperature Controlled fans often aren’t set for the operating range I want and may not have the sound/flow characteristics I’m looking for. I want to be able to pick almost any 3pin case fan and have a controller I can pretty much set during the build, and forget, and maybe revisit to tweak after the first several months when the fans are broken-in, or when I add/replace a fan. I want it to measure the case’s exiting air temperature and automatically adjust the case fans speeds. …I want to be able to set the fan controller’s output voltage/temperature ramp at the voltage and temperature range I want….

Is there a relatively simple circuit diagram using common parts that I can get at my local RadioShack or electronics store for the following?
Is there somebody out here that would like to take on a design challenge?:

NTC Thermistor-based voltage controller running off a 12VDC source so that…
• It supplies 12v between a temperature point I set (using a mini-screwdriver multi-turn variable resistor?) between 35DegC and 50DegC, and higher temperatures,
• A voltage point I set (using a mini-screwdriver multi-turn variable resistor?) between 2 and 12V at a temperature point I set (using a mini-screwdriver multi-turn variable resistor?) between 20DegC and 34DegC, and lower temperatures,
• A relatively linear or gradual ramping-up of the voltage between the two set points,
• Logic so the small variable-speed/volt DC fan motor to be driven starts at a full 12V when the controller powers-up cold, and then, in about 2 seconds, drops to the controlled voltage.
• The controller needs to be able to supply up to 12Watts at 12V - for multiple fans of the same model
• The thermistor needs to be on a 40cm lead – to reach where I want to measure the temperature
• With no load, the controller should consume very little power; Under load as little as possible.
• Power input from a std. computer PSU 4pin pass-through Molex plug
• Output red & black wires to a std. 3pin male fan plug (like a 3pin motherboard fan header) w/yellow speed-sense back-feed wires to both 3pin & 4pin female blocks that would be used to connect to motherboard fan header(s)
• Low power components on inside of the controller box; heat sync on outside?
I should be able to set the temperature-voltage curve, within the above parameters, to look something like:

(if picture not possible here, it looks like a constant 3.75v between 15 and 27DegC, and then gradually ramp up to a full 12v at 42DegC and higher temperatures)

…with me being able to change both the lower inflection point temperature and voltage, and upper inflection point temperature.

All I think I know I need is a NTC thermistor, probably at least three multi-turn potentiometer/trimmers, a power transistor, a little project board [& box], and other assorted resistors. But how to put them together?

And would it be easy to add a second output to this controller, using the same thermistor and temperature range settings, and have two outputs for different set-point voltages across the commonly set operating range? If I use two different models of case fans, I likely want the 2nd ramp to idle at a different voltage. (or maybe I just build a second controller)

ces
Posts: 3395
Joined: Thu Feb 04, 2010 6:06 pm
Location: US

Re: DIY Temperature Controlled Case Fan Controller Design

Post by ces » Fri Apr 29, 2011 11:47 am

May I propose the approach you are taking is akin to that of the swordsman here:
http://www.youtube.com/watch?v=4DzcOCyHDqc :)

An alternative approach is to use some quiet fans (Nexus or slipstream) running at 800 or less RPMs set at a fixed voltage. Get a good CPU cooler. And for most people that is all they will need.... and it will be quiet and cool

BruceMellen
Posts: 9
Joined: Mon Jun 07, 2010 4:11 pm
Location: Rochester NY

Re: DIY Temperature Controlled Case Fan Controller Design

Post by BruceMellen » Fri Apr 29, 2011 1:04 pm

Ahhhh… but the swordsman died. I would like to see if someone would design us swordsmen the tool to defeat the gun holders and those that carry 'heat', being used to oppress us. Mere quiet fans set at a low voltage will keep us enslaved. I want to be free…

I like my Gelid Tranquillo cooler - it keeps my CPU under 45DegC running at 100%. And I'm striving to make my case-top 200mm tri-cool fan and other case good fans even more quiet before the summer heat, with either trial-and-error resistors & start-capacitors, or the controller I'm proposing that many in related forums could have benefited from. I don't even care if some entrepreneur takes this idea, has it built in Taiwan, and sells them, as long it is without the bling.

ces
Posts: 3395
Joined: Thu Feb 04, 2010 6:06 pm
Location: US

Re: DIY Temperature Controlled Case Fan Controller Design

Post by ces » Fri Apr 29, 2011 4:40 pm

BruceMellen wrote:trial-and-error resistors
Well this isn't exactly what you are looking for, but it is a simple and crude way to do reproducible experiments with various combinations of voltages:
http://www.performance-pcs.com/catalog/ ... s_id=25981

cmthomson
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Location: Pleasanton, CA

Re: DIY Temperature Controlled Case Fan Controller Design

Post by cmthomson » Sat Apr 30, 2011 5:59 pm

Take a look at the Noise Magic NMT-3. Compatible with all 3-pin fans, and can be used in combination with SpeedFan or other software (or FanMate or other hardware) to auto-adjust speed settings based on ambient temperature.

I use two of these in my system, and they really work well.

ces
Posts: 3395
Joined: Thu Feb 04, 2010 6:06 pm
Location: US

Re: DIY Temperature Controlled Case Fan Controller Design

Post by ces » Sat Apr 30, 2011 6:12 pm

cmthomson wrote:Take a look at the Noise Magic NMT-3. Compatible with all 3-pin fans, and can be used in combination with SpeedFan or other software (or FanMate or other hardware) to auto-adjust speed settings based on ambient temperature. I use two of these in my system, and they really work well.
Any more details on your experience with them?

Two threads:
viewtopic.php?t=34780
viewtopic.php?p=305009#305009

Seems like them come in two versions:
http://www.frozencpu.com/products/5299/ ... rsion.html
http://www.frozencpu.com/products/5298/ ... ector.html

BruceMellen
Posts: 9
Joined: Mon Jun 07, 2010 4:11 pm
Location: Rochester NY

Re: DIY Temperature Controlled Case Fan Controller Design

Post by BruceMellen » Sun May 01, 2011 2:30 am

I've also just run across http://geoffg.net/fancontroller.html and will look into further.

Has anyone heard of this DIY kit before?

And has anyone seen a [nicely] pre-made Y cable that allows red/black power from a PSU molex, a female plug w/just yellow speed-monitoring wire to connect to a 3pin or 4pin motherboard header, and a 3pin male (red/black/yellow) for the fan itself to plug into?

Hypernova
Posts: 124
Joined: Sat May 31, 2008 2:33 am
Location: Australia

Re: DIY Temperature Controlled Case Fan Controller Design

Post by Hypernova » Sat May 14, 2011 12:44 am

Well, I can pass on some of my designs from my own custom controller. Although for your purpose "beyond overkill" would be an understatement. And in a strange twist of fate my first job out of uni this year is as a R&D engineer in Taiwan writing firmware for high powered (~kW) BLDC motors.

BruceMellen
Posts: 9
Joined: Mon Jun 07, 2010 4:11 pm
Location: Rochester NY

Re: DIY Temperature Controlled Case Fan Controller Design

Post by BruceMellen » Mon May 16, 2011 4:55 pm

After realizing I’m over my head w/respect to the electronics but knowing the desired functionality and a good UI ….
Here is my dream hardware and software fan control design for some entrepreneur …

A Microprocessor controlled mini-board that doesn’t take even a small low profile internal 3.5” bay – can it screw to a fan corner? (Gee, it would be nice for motherboard manufacturers to incorporate this onto their motherboards)
• Several temperature probe headers for probes on 60cm leads – to place near hard drives, near CPU/GPU coolers, at rear &/ top case exhaust. The probes themselves should ship in a couple pieces, including a black braided wire sheath, so they can be cut to the builder-desired length and the plug can be attached. Maybe, with future software beyond what is described below, a probe could be used to look at intake air and even effect some fan speeds based upon temperature rise.
• A bunch of fan headers that can be configured / jumpered in some way for either 3-pin or PWM fans – so the builder can choose/mix&match the fans they like.
• A few of those Fan headers should fully handle big/5 watt fans; the remainder handling 3watts
• Connection to a motherboard USB header, for communication
• No requirement for a dedicated external bay display/control
• Enough software running as a Win7 32/64 bit system service so…
o CPUID’s Hardware Monitor and SpeedFan can see the board’s temperature probes and fan speeds,
o SpeedFan and other popular applications (including the one described below) can control the board’s fan speeds,
o AND, maybe, so the board’s microprocessor can see and perhaps independently act upon temperatures obtained from within the PC system (CPU/GPUs, SMART/Winbond/Intel/… devices)
• The board’s microprocessor should start configured fans at full PWM/voltage until the fan is seen to be running.
• The board’s microprocessor needs to remember any last loaded profile so it can do its job without the OS loaded, but running the configured fans that are dependent upon the OS for temperature readings, at maximum speed when getting no response from the OS – see application proposal to better SpeedFan.

The New Application – FanSpeed?
• Preferences: - The intent is to continually run the monitoring/controlling portion of the application
o to run upon boot as a service
o to run minimized in the notification area icon tray upon login
o to run without presence in the task bar, and
o to minimize to the notification area icon tray upon closing, rather than exiting. Can only exit via right click on tray icon.
o Tray refresh frequency, in seconds, defaulting to 1
• Right clicking the tray icon allows for the opening of the configuration UI, or truly exiting
• Hovering over the icon displays balloon information specified through options in the configuration
• Besides the probes wired off this controller, the CPU/GPUs, motherboard, and other SMART/Winbond/Intel… (in CPUID Hardware Monitor) device temperatures should also be able to be used as temperature probes
• The configuration UI should incorporates some / improve-upon aspects of ASUS’s PC Probe II & FanXpert, SpeedFan’s Beta fan control UI, and other controller applications
• UI for each temperature probe: allow builder to enable and name each temperature probe, enable an alarm temperature for it, and checkmark alarm blinking try icon / tray balloon information / user-chosen sound / open full window to report it. A closeable balloon would give both the alarm probe name(s) and temperature(s)
• UI for each fan in a different window:
o Allow builder to enable each fan header and name the fan
o Enter both the minimum manufacturer rated speed (warn user to not set too low, initial default to 2000rpm) and maximum desired speed (initial default to 9999rpm)
o Choose which temperature probe to use, or the highest (or average) of a number of chosen probes (like highest of several hard drive temperatures, or highest of case exhaust temperature probes)
o After suggesting to the user to do this when the CPU is idling, the app can proceed to test/learn/calibrate the fan to learn the PWM/voltage needed for that desired range of speeds. The calibration may take a couple minutes or so (due to fan speed stabilization at a certain PWM/voltage) and is needed to save the profile. The application should then know 26 PWM/voltage points from the ‘minimum speed’ (lesser of the user-set rated minimum speed & full PWM/voltage speed), up to the ‘maximum speed’ (lesser of the maximum user-desired speed & full PWM/voltage speed). Each point is 0%, 4%, 8%, 12%, … 96%, 100% above the minimum speed (for 26 points including 0% and 100%)
o Allow builder to then graphically (horizontal: temperature from15DegC to 100DegC in 5DegC increments, vertical: fan 0% to 100% speed range from above, in those 26 increments, scales shown) effectively choose
 temperature at which fan turns on (green/default to 15DegC) to minimum speed (0% being the minimum speed),
 temperature at which fan starts its speed ramp (blue/default to 22DegC),
 temperature at which fan runs at maximum speed (orange/default to 40DegC) (100% being the maximum speed desired),
 an intermediate temperature/fan-speed point along the calibrated ramp immediately above, if the builder doesn’t want the fan speed to increase strictly linearly (blue/orange-mix/default to 30DegC and midpoint between min & max speeds,
 an audio alarm temperature at which the fan then runs at full PWM/voltage
All in a way similar to FanXpert, but where a short line comes from below to the green dot that can be dragged left/right across the graph bottom (@minimum speed), the line continues to a left-right moveable (@minimum speed) blue dot to the right of it, the line continues to a moveable tan dot to its right and above, the line continues to a left/right moveable orange dot to its right at the top (@maximum chosen speed), and a left/right moveable red dot to the right of that, where a short line goes straight up to indicate maximum PWM/voltage. Allow these changes and show the current system results – similar to FanXpert.
 The application will then know the PWM/voltage to apply to get the fans to do what the builder wants from a 0% to 100% speed ramp.
o Also allow the entering of an alarm percentage and user-chosen sound… for when a fan is running more than that percentage below its calibrated speed for more than a user-chosen number of seconds. A typical reason for a fan to be running below what is anticipated, is accumulated dust or a fan dying/dead bearing,
o Also enter how long (minimum time) the fan is to run once turned on, so that it does not short-cycle (default to 99999 seconds)
o Also enter if current information is to be displayed in the tray icon balloon, and/or in a separate tray icon
o The application should allow the builder to save and load these profiles to run with, downloading what is needed to the microprocessor as well.
• The user should have something in the Windows 7 tray to see, at least, temperatures & fan speeds, and get alarm informative balloons
o Hovering over the tray icon will balloon a builder-configurable selected table of fan names, speeds, associated probe temperature and a percentage/color to indicate where on the ramp it is, black=off, green=on but below start of speed ramp, running from blue/minimum to orange/maximum on the ramp; red if a temperature is over the maximum speed value ; blinking if in an alarm state
o This common tray icon should change color to represent the fan highest on the ramp or beyond, and blink if in alarm.
o A closeable tray balloon explanation should appear for new alarms
o The builder should be allowed separate tray icons for selected fans/probes… constantly showing the associated temperature & color (15DegC blue to alarm red) or percent up the ramp and color. Hovering over the icon will show the name.
• The monitoring application should be able to create a date/time stamped log file of all known information, in a format, with column headings, readily importable by EXCEL, in a user-chosen directory, with a user-defined log-entry frequency, in seconds, creating the next log file each calendar day, and deleting old files at that time, if the folder exceeds a user-specified size.
• The application should also be able to selectively report other things CPUID’s Hardware Monitor, CPU-Z, RealTemp sees (CPU/GPU/core/bus/qpi clocking/multiplier) in a window, including minimums and maximums and being able to clear them when desired, when the user clicks on the tray icon.

goloap
Posts: 1
Joined: Tue May 17, 2011 3:27 am

Re: DIY Temperature Controlled Case Fan Controller Design

Post by goloap » Tue May 17, 2011 3:37 am

During my own search for something similar but much less complex I found this link http://www.bit-tech.net/modding/2001/12 ... ntroller/1 which I found quite good. I didn't make one to test if it's any good. But it fits my requirements of small, simple and customizable temperature range.

BruceMellen
Posts: 9
Joined: Mon Jun 07, 2010 4:11 pm
Location: Rochester NY

Re: DIY Temperature Controlled Case Fan Controller Design

Post by BruceMellen » Sun May 22, 2011 3:40 am

With a lot more searching, finding nothing worthwhile, and with considerable thought, I’d like to suggest this hardware/software combination: http://www.mellen.biz/fancontroller/
Do you want to automatically adjust your fan speeds based upon case temperature(s), and/or want some more fan headers of the type you want for the fan make/model you want to use, and monitor all your fan speeds in the best respected application out there? This relatively simple controller board, in conjunction with SpeedFan’s new fan control user interface (as of 4.44β), is a great way to automatically control your fans to keep your build cool, as quiet as possible, and safe. Tom’s hardware says that “If you are interested in regulating your fans, you should also furnish your system with numerous heat sensors. An alarm function triggered at critical levels should alert the user that the PC is getting too hot, or better yet, automatically take control of and adjust fan settings.” This solution is all that and more, without paying too much for it.
To obtain it, you have three choices…
  • 1) You need to ask your favorite manufacturer to make it so. Apply pressure showing a market, and manufacturers won’t want to be the last with the solution. Along with a personal note, send the information below to them, so they get a consistent picture. Are you listening Antec?, Silverstone? LianLi? Gelid? ArcticColling? Thermaltake? CoolerMaster? Zalman? Scythe? Noctua? NZXT?
    2) If some electronics, Win7 programming, and marketing people can get together and get it prototyped & proven, they could perhaps work something out with a PCB design & assembly service to get it to market at a reasonable price point, or
    3) Arm-twist a local university that might entertain this as an interdisciplinary project that could be subsequently run with…
Write me at fancontroller@mellen.biz if you have further improvements for the product or visit http://www.mellen.biz/fancontroller if you want the latest thoughts on the product. I’d be glad to get this rolling…

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