controller Vs Display

[rajanm1]

i have just bought a phase change system and it already has a k type temp probe in the head unit but no display or controller. so i was wondering if there is any difference between just having a display to display the temperature and a controller if i run it 24/7 or just to bench?
thanks
rajan

[{.bLanK} GoD]

Glad to hear you have taken on the extreme cooling bug. And welcome to Xs:)
Did you buy a custom cooler? Who from may i ask? Do you have pictures?
To answer your question, a custom controller like the G-froster and Unseen's controller will monitor your temps amongst many other things. Safeties built in to shut down pc, fan speed adjusting, windows software. The list goes on. I advise you read through their threads to see if you want to spend the money on what the controllers offer.
My own opinion, A phase change controller for the win. They look trick as hell too

[kayl]

another advantage of a controller over a temp meter is that you dont have to keep changing the batteries

[boshuter]

If you are going to run 24/7 then a controller is a must imo. For benching only a display is all you need.

I would love to find a good temp display that could be mounted in the case and be accurate... doesn't have to be perfect, just something that could monitor evap temp without having to have a meter hooked up.

[star882]

You can build your own controller. I'll make a design that uses parts available from a local electronics store.

[{.bLanK} GoD]

You can build your own controller.

You sure can. (http://xtremesystems.org/forums/showthread.php?t=122634)

[rajanm1]

if i get a controller i would want it to link to the PC, could i build one that could do that and roughly how much would it cost?

[star882]

What features do you want? It could be as little as $20 for a basic controller to more than $300 for a very advanced controller. (The control/power board in an 8 way Britney "mini supercomputer" cost roughly $500 to design and build!)
I plan to make a controller in the $20-30 range. If low cost is all you care about, you could just have a relay that turns on with the enable signal from the motherboard and a fixed thermostat (the type normally used to activate freeze protection devices) to switch on the PSU with the motherboard.

[wdrzal]

another advantage of a controller over a temp meter is that you dont have to keep changing the batteries

If anyone has a battery usage problem with any piece of test equipment that has no jack to plug in a ac adapter, just install one. very simple ,just buy appropriate jack and voltage adapter,pick spot where there is room to drill hole & also for internal jack. buy & wire so like most units when power supply is plugged in it run off external power & when jack is removed the batteries take over .(if installed)

[star882]

If anyone has a battery usage problem with any piece of test equipment that has no jack to plug in a ac adapter, just install one. very simple ,just buy appropriate jack and voltage adapter,pick spot where there is room to drill hole & also for internal jack. buy & wire so like most units when power supply is plugged in it run off external power & when jack is removed the batteries take over .(if installed)
You'll also need two Schottky diodes unless you're using rechargeable batteries and an external charger.

[SexyMF]

I plan to make a controller in the $20-30 range.

You won't be able to achieve that cost using those National transducers you mentioned in my thread. I doubt I can be beaten on cost and versatility.

[star882]

By "controller", I mean the actual logic board itself. The power relay and temperature sensor are not included since it can be assumed they're part of the cooler unit.
With small CMOS logic chips a dollar or two each, it should be possible to make a very functional controller for under $20.
BTW, the price of an AD590 depends on which one you buy. I used the AD590LF simply because I already have some. If you check http://www.analog.com/en/prod/0,,764_811_AD590%2C00.html , you'll find some sensors that are just $2 each in large quantities. (Note that the calibration will not be as good, but still enough for our application. Ultra-accurate calibration is expensive!) I haven't really searched, but I think you can find even cheaper sensors.

BTW, I plan to design my controller to have a delay-on-break (anti-short-cycle) timer and basic temperature-based startup and shutdown in standard CMOS logic. I might add an Ashlee Simpson microcontroller for a front panel display and additional control functions. (I already have a large collection of logic chips so it'll be hard for me to optimize for price, since I'll likely use what I have.)

[SexyMF]

Well, all prices without tax, in 1000+ units look good. But you won't see anything near that price.

But all the same, good luck with your controller. I hope you will also publish the work so others have some alternative to purchasing certain controllers.

[star882]

Yes, I'll post a schematic once I finish the design.

[rajanm1]

thanks