Martinm210
02-08-2008, 11:20 PM
So I decided before I do any more thermal testing that I was going to find a way to log water/air temperatures automatically to ease the pain a little. When you start splitting degrees on two blocks, gathering more and more data seems to be key in making any worthwhile conclusions....so...
In the end I decided to go with a Crystal Fontz CFA633 for the following reasons:
-Logging of up to 32 digital thermal sensors
-Digtial Sensors are very accurate with extremely good resolution. .5C accuracy with .0625C resolution and .01C relative accuracy.
-Digital Sensors are digital so there isn't error introduced by the thermal wire (Resistance) leading up to the coupler or transistor, etc.
-Logging exports to excel.
So here are the sensors I started with, just 4 sensors, two for air on the radiator and two for the CPU loop, one inlet and one outlet. I chose to do this so I can measure any differences in outlet temperatures, I thought this may be something that will change with higher restriction blocks/nozzles, etc. It would also provide a secondary sensor to confirm the inlet is operating correctly.
http://img116.imageshack.us/img116/4518/crystalfontz3um9.jpg
This is how I integrated the sensors as thermal probes for measuring the water temps, low restriction, but good sensor placement.
http://img116.imageshack.us/img116/6982/crystalfontz4rk2.jpg
A standard Air or surface sensor construction, basic three wires and all wires can be connected in series which is nice.
http://img116.imageshack.us/img116/2384/crystalfontz5cj3.jpg
The LCD with the four temperature probes turned on the display. There is alot you can do with the LCD, I only know enough to be dangerous..:D
http://img116.imageshack.us/img116/8066/crystalfontz6ny3.jpg
And a short quick and dirty logging of both TAT and the CrystalFontz. As an added bonus they both log temperatures in the exact same time format so correlating the two along the X-axis is really easy.
http://img116.imageshack.us/img116/186/crystalfontz7en1.jpg
Some observations:
Water Inlet/Outlet temperature differences in this high flow setup(3GPMish) are so small, I can't even really measure it. I'll see if this changes with a high restriction nozzle setup. I always figured you'd see a degree or two even at these flow rates.
I did some calculations on specific heat and figured it takes about 350+ watts to change a 1.5GPM flow rate just one degree, so it would make sense I suppose that at 3 GPM, it would take nearly 700watts to change one degree. The E6600 doesn't even make a mark, or at least not one strong enough to measure.
TAT produces some wacky ups and downs, check out the swap between core 0 and 1 where they sort of switch places. I guess this all the more emphasizes the need to log temperatures for a very very long time to minimize some of this. I'm thinking I'll start testing and run it for at least an hour, maybe more just to gather more results to average. It's too bad it fluctuates so much, but it is what it is..
Resolution on the CrystalFontz Dallas DS18B20 Digital sensors (http://datasheets.maxim-ic.com/en/ds/DS18B20.pdf) and relative accuracy seem to be very good. You can see by the two water sensors that they hug the same temperature within the .0625 resolution very well, you can't even hardly tell there is a blue line under the orange one, but there is and those are two completely separate sensors.
It's a bit suprising to see the difference between the to radiator intake sensors. Lower to the floor the cooler the air and that's more significant that you would think...
Anyhow, it's working and I think I'm finally ready to do a little thermal testing. Going to let the computer do the work..:up:
The question is what should I use the other 28 channels for...:D
In the end I decided to go with a Crystal Fontz CFA633 for the following reasons:
-Logging of up to 32 digital thermal sensors
-Digtial Sensors are very accurate with extremely good resolution. .5C accuracy with .0625C resolution and .01C relative accuracy.
-Digital Sensors are digital so there isn't error introduced by the thermal wire (Resistance) leading up to the coupler or transistor, etc.
-Logging exports to excel.
So here are the sensors I started with, just 4 sensors, two for air on the radiator and two for the CPU loop, one inlet and one outlet. I chose to do this so I can measure any differences in outlet temperatures, I thought this may be something that will change with higher restriction blocks/nozzles, etc. It would also provide a secondary sensor to confirm the inlet is operating correctly.
http://img116.imageshack.us/img116/4518/crystalfontz3um9.jpg
This is how I integrated the sensors as thermal probes for measuring the water temps, low restriction, but good sensor placement.
http://img116.imageshack.us/img116/6982/crystalfontz4rk2.jpg
A standard Air or surface sensor construction, basic three wires and all wires can be connected in series which is nice.
http://img116.imageshack.us/img116/2384/crystalfontz5cj3.jpg
The LCD with the four temperature probes turned on the display. There is alot you can do with the LCD, I only know enough to be dangerous..:D
http://img116.imageshack.us/img116/8066/crystalfontz6ny3.jpg
And a short quick and dirty logging of both TAT and the CrystalFontz. As an added bonus they both log temperatures in the exact same time format so correlating the two along the X-axis is really easy.
http://img116.imageshack.us/img116/186/crystalfontz7en1.jpg
Some observations:
Water Inlet/Outlet temperature differences in this high flow setup(3GPMish) are so small, I can't even really measure it. I'll see if this changes with a high restriction nozzle setup. I always figured you'd see a degree or two even at these flow rates.
I did some calculations on specific heat and figured it takes about 350+ watts to change a 1.5GPM flow rate just one degree, so it would make sense I suppose that at 3 GPM, it would take nearly 700watts to change one degree. The E6600 doesn't even make a mark, or at least not one strong enough to measure.
TAT produces some wacky ups and downs, check out the swap between core 0 and 1 where they sort of switch places. I guess this all the more emphasizes the need to log temperatures for a very very long time to minimize some of this. I'm thinking I'll start testing and run it for at least an hour, maybe more just to gather more results to average. It's too bad it fluctuates so much, but it is what it is..
Resolution on the CrystalFontz Dallas DS18B20 Digital sensors (http://datasheets.maxim-ic.com/en/ds/DS18B20.pdf) and relative accuracy seem to be very good. You can see by the two water sensors that they hug the same temperature within the .0625 resolution very well, you can't even hardly tell there is a blue line under the orange one, but there is and those are two completely separate sensors.
It's a bit suprising to see the difference between the to radiator intake sensors. Lower to the floor the cooler the air and that's more significant that you would think...
Anyhow, it's working and I think I'm finally ready to do a little thermal testing. Going to let the computer do the work..:up:
The question is what should I use the other 28 channels for...:D