Multi-function temp/fan controller DIY (using some commercial components).Parts List
Power Relay 72J4442 1 6.64 Series:782; Coil Voltage VDC Nom:12V; Coil Resistance:160ohm; No. of Poles:4; Contacts:4PDT; Relay Mounting:Plug In; Carry Current:10A; Features:Plain Cover w/Flag; Relay Terminals:Quick Connect; Coil Voltage DC Max:12V ;RoHS Compliant: Yes 782XDX2C-12D MAGNECRAFThttps://www.newark.com/jsp/search/pr...sp?SKU=72J4442
Relay Socket 69K5576 1 3.50 Socket Mounting
IN Rail/Panel; Current Rating:10A; Socket Terminals:Screw; No. of Pins:14 ;RoHS Compliant: Yes 70-782D14-1 MAGNECRAFThttps://www.newark.com/jsp/search/pr...sp?SKU=69K5576
Relay Retaining Clip 64J8914 1 0.73 For Use With:Chassis/Panel and Printed Circuit Sockets ;RoHS Compliant: Yes 16-1342 MAGNECRAFThttps://www.newark.com/jsp/search/pr...sp?SKU=64J8914
EXT ENCLO SABRENT|EC-525K R N82E16817366013 1 26.54http://www.newegg.com/Product/Produc...82E16817366013
CONTROLLER ZALMAN| ZM-MFC3 R N82E16811999197 1 69.99http://www.newegg.com/Product/Produc...82E16811999197
Coolerguys Thermal Fan 840556086611 1 13.95 Temp Control = On 87F / OFF 80F Controllerhttp://www.coolerguys.com/840556086611.html
Internal Drive 4Pin Power 840556000662 1 2.25 Splitter Cable # CC2125Yhttp://www.coolerguys.com/840556000662.html
4 Pin Molex Power Cord 840556069683 2 1.95 Length = 36 inch Extension Cable 12 18 24 and 36"http://www.coolerguys.com/powerext.html
3-Pin Extension Cable / 840556069393 1 1.89 Inches = 36 Adapters for 3 Wire Devices, 12, 18, 24 , 36 or 48 Incheshttp://www.coolerguys.com/840556000013.html
SPDT Submini Toggle Switch 275-0613 1 3.79http://www.radioshack.com/product/in...ductId=2062498NOTES :
I left off the fans as they are not specific to the project. We used 2 of the Feser Triebwerk 120mm x 55mm fans and are more or less happy with them.
The Zalman fan controller was overkill. I had ordered it for something else and just ended up using it in tis project. There are much cheaper alternatives that would suffice.
I am not 100% happy w/ the Sabrent case I chose. It lacks a pedestal to stand it on it's side, and has rounded sides, which are nice to look at but becuase of that it has to lay flat.
I had to buy a power supply anyways, and for a few $$ more I got a case to go along with it to hold (and hide) everything. It also gave me someplace to mount the fan controller I wanted to use, since most (but not all) are made for mounting in a PC case.Motivation/Purpose :
The reason for building this was that I wanted to cool our entertainment center with the following requirements :
Cooling be automatic (only come on when needed)
Fan speed control (either automatic or at least manual, to control the noise level as needed)
Temperature monitoring (to see how well the fans were doing and if I needed to increase the speed)
There are several controllers out there that will control the fan speed based on temperature, but they had several drawbacks.
- The fans were always on, even when not needed (just running at their slowest speed -- at least the controllers I tested)
- The controller display was always on, even when not needed (at night it was distracting)
So I set about building a solution. I originally just wanted a device to piggyback off of one of the temp controllers like the Collerguys ones. But they only passed 12v, and most fan controllers required the 5v feed for their functionality. I couldn't find any that passed both the 5v and 12v. The answer for me was to put in a 12v 4 pole relaySteps :
I took apart the Sabrent case and took off the back power/control board (two screws hold it down), unscrewed and removed the fan audio connector (for CD-ROMs) completely from the case (to reuse the hole for the switch, more about that later) and snapped out a rectangle shaped cut-out in the back of the case right next to the power switch. I removed all non-essential cables, like the drive cable and unplugged the fan power connector (but left the fan in case I needed it to keep the case cool, more about that later too).
Then I routed the fan connectors and temperature probes through the cut-out and put the power/controlled board back on. The wires need to be passed through the holes before the power board goes back on since the cut-out is an extension of the box hole for the power plug and the extra opening is needed to get the larger fan connector ends through. Then I held the wires out of the way (keeping them in the cut-out) and put the power board back in.
I cut the Molex extension in half and cut the male end off of the 3 pin extension. I also cut 2 pieces of scrap wire (can use two of the wires from the 3 pin ext since only 1 is needed). then I soldered 3 wires to the SPDT switch, two loose and one coming from the ground on the 3 pin (the black wire). The black wire goes to one of the side post and the other two loose ones go to the center and other side posts.
Then I installed the switch into the hole that used to hold the audio plug in the back of the case.
Next I setup the relay. I took the female end and connected the 4 wires to the center posts of the relays 4 poles. This would be the line side. Then I took the male end and conencted the 4 wires to the corresponding posts of the 4 poles on the NO (normally open) side*. I then put a wire from the 12v+ (yellow wire) contact on the line side and connected the other end to the relay coil terminal. I put the wire from the center post of the switch that I installed and connected it to the other side of the relay coil. Then I took the other loose wire from the side post of the switch and connected it to the terminal that had the ground on the line side (the black wire next to the yellow one). All of the wiring is now done, aside from plugging in the molex power plugs.
* If you use a single throw relay. I goofed and ordered a double throw instead of a single throw relay (4PDT vs. 4PST). I could have maybe saved a dollar on a single throw, but it isn't a big deal.
I then installed the Zalman fan controller and mounted the relay and Coolerguys temperature controller (used double-sided tape for now). I plugged in the molex splitter into the power supply at the back and plugged one of the connectors into the temp controller and the other into the female connector (on the line side of the relay). Then the male molex on the load side of the relay got plugged into the Zalman. I then plugged all of the fan and temperature probes into the Zalman and Coolerguys controllers and the female 3 pin connector (attached to the switch in the back) got plugged into one of the fan connectors on the Coolerguys controller.
Everything is now ready to go. The purpose of the switch is to provide a manual/automatic selection. Not needed if you want to just run it always in automatic.
I installed the switch in mine vertically, so in the up position it is in manual mode (IE: Just "on"), in the down position it is in automatic (only comes on when the temperature controller is triggered, which w/ the Coolerguys one it is fixed at 87f on, 80f off, IIRC). I also left one of the fan controller temp probes in the case to allow me to monitor the temp in there when it is running, so see if I needed to connect the small case fan to one of the 12v power sources to keep it cool inside. I suspect not, but that option is there along with a way to monitor and determine if it is needed.
I tested by putting it in manual and making sure everything comes on, then putting it into auto and holding the temp probe to heat it up and making sure it powered up the fan controller. I then closed everything up, put it into our Ent Center and plugged all of the fans and what not into it. I set it in manual mode to adjust the fan speeds to a level that isn't bothersome or too audible from our viewing/sitting location. I then placed the temp probe from the temp controller in the hottest spot in our Ent Center (right above our receiver/amp) and put the temp probes from the fan controller into different places to monitor the temp (monitoring only available when the fans come on). I only plan to use the temp monitoring (IE: pay attention to it) in the hotter summer months to ensure that the fans are doing their job(s)
.Things I would do differently/still left to do :
Add a longer temp probe from Coolerguys to the temp controller (and possibly an ext so that the connection is outside of the case so I can unplug it to remove the case from the Ent Center, w/o having to re-route the main temp probe each time)
put grommet around the cut-out to avoid problems w/ any sharp/rough edges
wrap all of the cables coming out of the case into 1 bundle that fans out jsut a few inches from the end.
figure out a stand for the Sabrent case (or change to a case w/ a stand)
add an "all in one" connector between the wires coming out of the unit and the fans/temp probes/etc. It all depends on how often I find myself taking it out or moving it around (which I don't expect to be that often, once I get it settled in).
Maybe add another "zone" to the unit (by adding another temp controller to monitor/react to a different area of our Ent Center). Wouldn't be too hard and would only cost about $15 or so to do, but I would need to test running two temp controllers in parallel.
I would definitely use a much cheaper fan controller but this one was available and unused, so I went with it. Total cost (w/o the fan controller or fans) was just over $60. I leave off the fan controller and fans because there is alot of possible variation there and really comes down to personal preferrence. And the choice has no bearing on the "project", any one would work, so long as they are a 5.25" PC fan controller and compatible fans (compatible with the PC fan controller). For that same reason I didn't bother with any pictures of the fan installation or components in our setup. They are irrelevant to the controller build
Except that I am a control freak, this all could have been done more simply and cheaper, but what fun would that have been ?
This project falls into the category of the journey being as important as the destination. Plus it looks really cool (points for geek factor
The pictures leave much to be desired (I used an older camera to snap them really quick while I was building it). It is already tucked into our Ent Center, but I will need to take it out, and apart, again when the longer temp probe gets here and I will take better pitures then, if anyone is interested.
I will also try to put together a wiring diagram later on today, but wanted to share this just in case anyone else was as bored as I was and wanted to build something similar
First picture is of everything installed, but I unplugged a couple of the power cables to move them out of the way to better show the other components. Unfortunately I had already built it when I thought to start taking pictures to share, so I don't have a step by step photo documentary
The next one is of everything plugged in and the spare cables just curled up (or shoved in) the case.
This one is a shot of the back of the case, with the manual/auto toggle switch to the right of the on/off power switch.
Here is a horribly unfocused shot of the unit fully assembled. (to be retaken later this week, as time permits)
Here is what the Zalman looks like powered up.