Type K Thermocouples with DL1

marck_c
Posts: 40
Joined: Sat Sep 06, 2008 2:37 am

Type K Thermocouples with DL1

Postby marck_c » Sat Sep 06, 2008 2:39 am

Hi folks, I am tuning a 4 cylinder turbo motor, and would like to know if it possible for the DL1 to accept the inputs from standard Type-K thermocouples for the purpose of logging each cylinders EGT. Can the DL1 properly read the thermocouples' voltage or is a thermocouple amplifier required? Thanks in advance.

faraday
Posts: 267
Joined: Sun Feb 25, 2007 1:18 am

Postby faraday » Sat Sep 06, 2008 3:40 am

http://www.race-technology.com/thermoco ... _2_63.html or equivalent is required. It is not my area of expertise, but I understand that it may well be possible to buy and certainly make your own multi-channel amplifier and save a few quid.

Are you planning individual cylinder mapping (pretty serious), or are you just curious :?:

marck_c
Posts: 40
Joined: Sat Sep 06, 2008 2:37 am

Postby marck_c » Sat Sep 06, 2008 3:58 am

Yes I am planning individual cylinder mapping, which is pretty serious. Any idea where I can get some info on how to make a multi channel amp. The RT amp ($145 x 4) is a pretty expensive way to do it. $580 is much more than a few quid!!

faraday
Posts: 267
Joined: Sun Feb 25, 2007 1:18 am

Postby faraday » Sat Sep 06, 2008 4:05 am

:oops: I'm probably as ignorant as you may be on this one. I would go to Google...

There are kits for all sorts of things. I'm guessing that there will be too much rather than too little info on this topic.

How difficult is it being a car nut in Jamaica :?:

marck_c
Posts: 40
Joined: Sat Sep 06, 2008 2:37 am

Postby marck_c » Sun Sep 07, 2008 4:48 pm


faraday
Posts: 267
Joined: Sun Feb 25, 2007 1:18 am

Postby faraday » Mon Sep 08, 2008 12:47 am

I haven't done any new literature searching, but thought I should look again at some stuff I saved earlier this year when I was investigating RTDs. My first thoughts were that this AEM device was overkill. Perhaps thermocouple metering/amplification is a little complex for a cheap kit and this thing is good value afterall...

Here are a couple of links that might be of use:
http://www.picotech.com/applications/thermocouple.html
Watlow (http://www.watlow.com/) has some good basic stuff, but I can't find a live link to a tutorial book I've downloaded. You can email me (rotoflow at optusnet dot com dot au) and I'll send it.

Hope hurricanes miss you and blow out before they hit your neighbours named as being on the paths.
Could there be two marck_c in Jamaica?

I see chat about a rotary and now Honda chap and Youtube footage.

:)

marck_c
Posts: 40
Joined: Sat Sep 06, 2008 2:37 am

Postby marck_c » Mon Sep 08, 2008 3:43 am

Just me. I used to race a SCCA GT-4 Civic 1200, and also an Evo 1.

faraday
Posts: 267
Joined: Sun Feb 25, 2007 1:18 am

Postby faraday » Mon Sep 08, 2008 5:25 am

So is your Civic the "King" car?
The way I read Jamaican forum chat, that appeared to be a Mar(c)k Viera project.

It looks like Australian club racing is very similar to your activity. You may be able to secure a little more commercial sponsorship because it appears that your club racing is "The" racing. V8 Supercars in Australia has grown to be more "professional" than perhaps our economy/market can ultimately bear. It is unashamedly run as an entertainment rather than a technical sport. As the only motorsport in Australia that gets regular live commercial TV time, it absorbs almost all available sponsorship.
We have more interesting categories from the engineering stance. These rely on largely scarce private wealth and obsessed owner/drivers.

I suppose, however, that to take your "product" to several regional circuits is more expensive as it involves more than road transport. Even if the R-T thermocouple amplifier is over-priced, we are lucky that the DL1 offers such great value for money. Nevertheless, I battle with the perception in local club racing that Data is too expensive for amateurs.
:cry:

Whatever level of outside funding you may benefit from, I see that as appears to be the case all over the world, the sport would not exist without many volunteers. Well done for managing to contribute in that area too.

Does an SCCA history imply that you don't love cricket?

:D

marck_c
Posts: 40
Joined: Sat Sep 06, 2008 2:37 am

Postby marck_c » Mon Sep 08, 2008 12:20 pm

Yes the King car is mine (was I sold it recently to concentrate on the new project). And yes I think cricket is the most boring sport in the world.

Turby
Posts: 296
Joined: Thu Nov 17, 2005 2:28 pm

Postby Turby » Mon Sep 08, 2008 1:09 pm

I've done this myself for a twin thermocouple amplifier for measuring the efficiency temperature drops across a water /air intercooler.

My circuit was based on the Analog Devices AD595 chip and has been in use for about 3 years with no problems. The circuit is more or less exactly as described in the following data sheets - but I did increase the amplification from the standard 10 mV per degree to (IIRC) 20 mV per degree to make better use of the voltages for the temperature range I was measuring. For EGT's you will need to provide 12v which will allow up to 1000 deg C...

Chip data sheet http://www.analog.com/static/imported-files/data_sheets/AD594_595.pdf

Also look at the application notes AN-369
http://www.analog.com/static/imported-files/application_notes/34661261AN369.pdf

and AN-274 http://www.analog.com/static/imported-files/application_notes/13282741AN274.pdf

The AD595 isn't exactly cheap, but can sometimes be found on ebay or obtained as "samples" from AD themselves.

The alternative to using multiple AD595's is to use one in conjunction with a PIC microcontroller to multiplex the single AD595 input to multiple analogue putputs (using another chip such as a D/A Converter from AD again ) ... Though I suspect the time and effort isn't justified for a one off project.

faraday
Posts: 267
Joined: Sun Feb 25, 2007 1:18 am

Postby faraday » Mon Sep 08, 2008 1:30 pm

Great information.

Can you venture an opinion as to what a maximum bid price should be :?:

Turby
Posts: 296
Joined: Thu Nov 17, 2005 2:28 pm

Postby Turby » Mon Sep 08, 2008 1:49 pm

I presume anything less than full price from a vendor as RS / Farnell etc.

There are several different variants - ranging in price / precision from the higher spec AD595CD (around $20 each) to the lower spec AD595AQ ($7 each).

Probably best off getting any AD595 ... Also factor in a small price of matrix board, mini K-thermocouple connectors and thermocouples. I also used a small LED to show error condition - its all in the data sheet ;)


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