4ch EGT meter with Propeller, QVGA LCD, microSD, USB , MCP3208, speaker, openso

tripp

Hi all.

I am almost done with my last project, a 4ch EGT meter.



It has four inputs for·TC-K.
Parallax Propeller CPU running at 96 Mhz.
2.8 "TFT LCD with touchscreen.
Built-in speaker.
MicroSD memory with FAT16 file system.
USB connection for communication with PC.
8 AD channels with 12 bit resolution, of which two are·additional protected, and two that go to the touchscreenen.

I will·write software for PC where you will be able to adjust the alarm levels, choose colors for text, etc..
Considering to release·the firmware as open source.
Do you think i would benefit from it, or someone would copy and sell the hardware?
Is there anyone here who would think it would be fun to help develop the firmware?
Now there are functions for logging, peak and hold, adjust the alarm levels.
Missing some features?

Here is a short video: <!-- m -->http://www.youtube.com/watch?v=X3_brxQ5Jzo



And some more pictures:

smbaker

Very nice looking! What's the intended application? Aviation? Automotive?

As far as the UI, I've always been partial to bar graphs. Always wanted something like this: http://www.transair.co.uk/product4.asp?SID=2&Product_ID=7865 but never wanted to deal with all of the installation effort (or, of course, the cost).

If you have additional A/D channels available, then I imagine intake temperature, cylinder head (or coolant) temperature, and/or oil temperature would all be handy to have in such a device.

Leon

What is EGT?

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Leon Heller
Amateur radio callsign: G1HSM

hover1

Exhaust Gas Temperature. I monitor my 2-cycle aircraft motors with EGT. It's crutial in tuning the carbs. CHT (Cylinder Head Temperature) also helps but does not react as fast as EGT.

Jim


PS Nice job Tripp!

Capt. Quirk

In my opinion it's not difficult to make a thermocouple board. If someone wanted to sell one, and had the resources to do so, they would need to substantially modify it for their intended market. Seems like every open project I come across, there is at least someone benefiting from it.
In this case though, I think your project would benefit from a group approach. In my projects thermocouples are are·normally just one piece of a larger project.
Looks like you are using MAX6675's for your cold-junction compensation?·



Bill M.

One more thing, I noticed there is an Xtune company that makes headers for cars, with the same logo.



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Post Edited (Capt. Quirk) : 6/8/2010 12:03:43 AM GMT

hover1

When you say USB to PC to adjust levels, do you mean program the Propeller and then the unit will be stand alone?

I currently monitor my crafts outfitted with Rotax 503’s with this device:



Standard K-type Thermocouple on both EGT and CGT.

Data logging is a sure plus for a product like this. I have trouble keeping an eye on the tach and four temps at 40 MPH on the water when I am trying to jet my carbs for max output.

Your·screen size is nice. Touch screen may not be water friendly in my environment, though. Screen sealed behind plexi, with waterproof pushbutton for Record On/Record Off would be on option.

Without Probes·the EMS-503·would sell for about $200.00US

Post Edited (hover1) : 6/8/2010 1:09:55 AM GMT

Capt. Quirk

What are your Cyl. head temps normally (say at·idle, mid and full throtle) and do you have one cylinder that seems to run hotter?

WBA Consulting

Really nice project! I can already see another use for the layout: Reflow profiling. Could easily be used to characterize a toaster oven to create very consistent reflow profiles. This would look really nice on the front of a modified toaster oven for home reflow soldering.

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Andrew Williams
WBA Consulting
WBA-TH1M Sensirion SHT11 Module
My Prop projects: Reverse Geo-Cache Box, Custom Metronome, Micro Plunge Logger

hover1

I'm not usually worried about CHT, it never runs over 400F.

EGT:

Full power - 900 to 1000 degrees F (about 950 being very typical). Lower temp because a lot of fuel/oil cooling.
Cruise power - 975 to 1125 degrees F (1075 is the target)
Reduced power· - 1000 to 1150 degrees F. Having to back off in no-wake zones, wait hovercrafts don't make wakes, sore subject.

I try and jet the back cylinder to be no higher than 10-20 degree F above the first.

Max EGT on a Rotax 503 is 1250 F. It looks like the MAX6675 will handle up to 1873 degrees F.

Tripp, it looks like you have some room to fit a RTC on the board for data logging. Gotta pin left over for GPS?

Jim

Capt. Quirk said...
What are your Cyl. head temps normally (say at·idle, mid and full throtle) and do you have one cylinder that seems to run hotter?

hover1

Tripp,

Any updates on the project?

Jim

Harley

Nice pcb layout and good looking case.
Thanks for showing it off.

Where does the 'speaker' fit (on back side)?

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Harley Shanko

Timothy D. Swieter

Very nice looking case and styling to the product.

How about an alarm silence button? When testing with the lighter, of course the probe cools fast, but depending on the application it may not cool below the setpoint so fast and would driver the operator nuts!

I like the idea of trend graphs. Numbers are OK - an instantaneous value, but the useful information may be in how the temps are trending. Maybe spark lines to the right of the temps to show trends of the past configurable amount of minutes.

Is this a commercial product you are planning? What kind of selling price?

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Timothy D. Swieter, P.E.
www.brilldea.com - Prop Blade, LED Painter, RGB LEDs, 3.0" 16:9 LCD Composite video display, eProto for SunSPOT, PropNET, PolkaDOT-51
www.tdswieter.com

Capt. Quirk

I feel as though I rushed to judge, originally I googled xtune and found pictures of xtune headers. I was left with the impression you were in the United States or·at least·close by, certainly not half way around the world. Sorry. I was also impressed with your PropPad mini. Bare PCB $5, Serial LCD driver with 7 x 21 chars and 262k Font colors thread.

I have used the 6675's before, and have been disappointed with the 1/4 sec delay they require. But it is less of an issue with the Propeller, than with a Stamp or SX.

I used to believe that EGT's were the best way to tune an engine also, but I have found more pitfalls with EGT's than with CHT's.·CHT's react much faster than most people think. Also tuning is·easier because from idle to full throttle the·Cylinder Head Temp may only need to rise 50 degrees·F, or maintain a steady a temp throughout the entire rpm range.·In racing I find it easier also, because I can raise the head temps 30'F and produce max HP for a boost of power, or throughout the entire race.

Using CHT's and EGT's in conjunction is also usefull to watch their combined patterns to determine if detonation or pre-ignition·is occurring.

I have two thermocouple projects that I will start working on soon. But this time I am planning on using AD595's along with Sigma-Delta ADC's instead. One of the projects is very close to yours, except it is meant to adjust a carb or simplified injection system to keep the engine operating within a set parameter.· The other project will use a propeller(s) to·eliminate my current PC control of my dyno and it's data acquistion.

These may help you, Circuit Board Thermocouple Connectors, I have them on my current engine monitor.·Another tip, is to use braided type K, instead of solid wire thermocouples, if you have issues with breaking ends off.

Sincerely

Bill M.




Post Edited (Capt. Quirk) : 7/24/2010 7:41:09 PM GMT

hover1

I have to disagree on the reaction time between EGT and CHT. EGT is much faster in that it is instant exhaust gas temperature available immediately 2" from the piston, (in the case of a 2-stroke) . A CHT is tied to a thermal mass, (head and spark plug). It takes a while for the temp to change.

This is my experience with 2-cycle engines, with the CHT being installed right below the spark plug and pressed against the head.

If you are working with 4 cycle motors with sensors mounted at different locations than mine, then that might make a difference.

I do agree the combined readings are needed to tune an engine to peak performance.

I am interested in your findings. Let's continue in the Sandbox.

Best Regards,
Jim

Capt. Quirk said...


I used to believe that EGT's were the best way to tune an engine also, but I have found more pitfalls with EGT's than with CHT's. CHT's react much faster than most people think. Also tuning is easier because from idle to full throttle the Cylinder Head Temp may only need to rise 50 degrees F, or maintain a steady a temp throughout the entire rpm range. In racing I find it easier also, because I can raise the head temps 30'F and produce max HP for a boost of power, or throughout the entire race.

Using CHT's and EGT's in conjunction is also usefull to watch their combined patterns to determine if detonation or pre-ignition is occurring.


Sincerely

Bill M.

tripp

Today i got 10 alu cases back from CNC milling.





And i also made a win app:



Timothy D. Swieter: Is this a commercial product you are planning? What kind of selling price?
I think i can sell complete units for USD 270.

Heater.

That is one very neat sexy looking unit.

Every Prop user is going to want one.

I'd be happy if my mobile phone looked like that and was as tough.

ErNa

tripp wrote: »

Today i got 10 alu cases back from CNC milling.

And i also made a win app:

can you give more infos about the win application? what is the development framework?

AJM

Tripp,

Very nice design. It looks very professional.

Andrey Demenev

tripp, that's an awesome design!

Could you please provide some clues about how many the cases and millig cost you?

Capt. Quirk

That's a very nice box Tripp, looks great.

I have a question if you don't mind?

Edit: (If green is the color for type k lead wire in your country, please ignore below.)

I noticed you are using extension grade thermocouple wire from the box to the probes.
(1) Is the extension grade wire, more resistant to outside interference than lead wire?
(2) Since the effective temperature range of extension grade is about 1/4 that of lead grade, does that effect the accuracy of the measurements?

I have always used Lead grade for my engines and dyno testing, But I don't personally know if there is an advantage to extension grade. So I thought I would ask.

For Mr. Swieter, here is your competition: http://www.exhaustgas.com

One other thing; the reason I prefer CHT's, is with EGT's it's possible to get a lower than expected exhaust temp when the engine is lean (around 900'f)(But I'm assuming you already know this). With 2-strokes it is possible to make the engine hit the pipe twice, and the on second time the power increase is very large. While tunning one of these race engines I got on the wrong side of the curve once. But even that helped me to find new possibilities, but I doubt could be recreated without an inclosed engine compartment. (BM)

tripp

Capt. Quirk, The wire i am using is type-k extension wire.
And if you use copper wires you would get a cold junktion in the transition from copper to type-k.
Is extension grade = copper wire?

Andrey Demenev: i milled 10boxes and the cost was USD $70, i guess if i do 50pcs in the next run, the price per unit will be a bit lower, but i need to say that the CNC guy is my friend.


ErNa: The win app is made with MS C# 2008

Heater: Thanks

Jay Kickliter

I wouldn't mind something like this for my car. I frequently shoot the exhaust manifold with an IR thermometer to check for problems, but it isn't very accurate. I don't have much experience with gasoline engines, but on diesels like my car and the ships I work on, exhaust temp variance is often the first sign of compression or injection problems.

Capt. Quirk

Tripp,

Like I said before, I have always used lead grade. So I did some digging, and the most important fact I found for extending thermocouples: So long as the same type of lead and extension wire is used, it will not effect the accuracy of the measurement.

Keep up the good work.

Bill M.

tripp

Now are the five first units ready.
It takes a bit too long time to hand-assemble the cards I think.
Does anyone know where to get help with it and how much it costs?

I also added a function that displays wideband lambda value.