DIY_EFI Digest Friday, December 10 1999 Volume 04 : Number 687 In this issue: Re: maximum ON before damage Re: Stoich Sample HC11 EFI code in C Atmel 8535 for engine controller See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- Date: Thu, 9 Dec 1999 18:53:34 -0500 From: "Bruce Plecan" Subject: Re: maximum ON before damage | They are a bit slow to open and thus have a higher minimum ms before | stability is reached. approx. 2.5 ms. That number isn't even close to what diacom displays for a AUJP BCC, in a 90 1227730 ecm'd v-8. At idle.. | Lower resistance injectors are high current devices that must be | handled with respect. They will draw 3-5 amps and will self destruct | in seconds with out current limiting. The usual ratio being 4:1. Not from what I've seen. | They are fast to open 0.4 - 0.9 ms and thus need to be limiting very | soon after saturation. | The limiting factor with any injector is the max. time in ms available | at max. rpm. If that rpm is say 6,000 rpm we have 10 ms total. | If it takes 1.2 ms to open (saturated type) and 1.1 ms to close you | only have 7.7 ms left. Just to make things difficult the first period | of 1.2 ms has NO flow. So really that 2.5 ms lower limit (for | stability's sake) | means you have 2.5 -8.9 ms to play with. If it takes 1.2 to open, how's it run with an injector pulse width of 1.1 at idle, or even 1.3ms. Just curious how the numbers work here Grumpy ------------------------------ Date: Thu, 9 Dec 1999 22:02:07 -0500 From: "Clare Snyder" Subject: Re: Stoich This is a multi-part message in MIME format. - ------=_NextPart_000_003E_01BF4291.0905A800 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable believe what you want to believe - I asked see: http://www.chemical-stoichiometry.net/Resource_Titlepage.htm http://www.chem.ualberta.ca/~plambeck/che/course/p0304x.htm http://www.compusmart.ab.ca/plambeck/che/p101/p01172.htm http://www.chem.ualberta.ca/~plambeck/che/p101/p01035.htm http://www.compusmart.ab.ca/plambeck/che/p101/p01033.htm http://www.chemical-stoichiometry.net/Tutorial_Titlepage.htm http://www.chemical-stoichiometry.net/ http://www.chemical-stoichiometry.net/tutorial.html http://www.collingwood.org/chemistry/Curriculum%20Docs/ch1111.htm http://www.chem.ualberta.ca/~plambeck/che/struct/s0201.htm http://www.chemical-stoichiometry.net/begin_student.htm http://www.compusmart.ab.ca/plambeck/che/course/vn41505x.htm http://www.chem.ualberta.ca/~plambeck/che/p102/p0511x.htm and http://www.chem.ualberta.ca/courses/plambeck/p102/p02085.htm to start with. Says if anybody is full of BS it's not me. Stoiciometry in many points = of reference - other than combustion. An excerpt from the last reference: Stoichiometric calculations involving redox reactions always begin with = the balanced redox reaction. Once the balanced redox reaction has been = obtained, the mole ratios will give the desired stoichiometric = information. ............. Combustion is a Redox reaction (oxidation/reduction) I've been told to make sure I've got my facts straight before posting = "opinions" - the definition I gave may be a gross simplification - but = the facts are the facts. Now, as for stoich being a moving target - A theoretically stoich = mixture may not behave as stoich under certain conditions - something to = do with elemental vs radical oxygen - elemental oxygen is not as = reactive as radical oxygen, so if the O2 can be dissassociated into 2 X = O, and the Hydrogen and Oxygen of the hydrocarbon fuel dissaciated into = hydrogen and carbon, the reactions of oxygen + carbon =3D carbon = dioxide, and hydrogen + oxygen=3Dwater can become stoichiometrically = correct, Changing the reaction of nitrogen + oxygen=3Dnitous oxides (or = oxides of nitogen - NOX) in the cyl can and does change the = stoichiometry of the reaction in the cyl. This is, in effect, what EGR = does to an engine. By inhibiting the formation of NOX the actual mixture = ratio of gasoline and air required can be can be changed. Decrease NOX = production and the mixture required for a stoichiometrically correct = combustion of the fuel can be richened because more oxygen is available = for the desired reaction. - -------------------------------------------------------------------------= - ------- ----- Original Message -----=20 From: Phil Lamovie=20 To: Clare Snyder=20 Sent: Thursday, December 09, 1999 10:02 AM Subject: Stoich =20 =20 Hi Clare,=20 Stoich is a point that moves with conditions ?=20 ABSOLUTELY IMPOSSIBLE !=20 is the mixture required to convert ALL of 2 elements to a compound=20 TRUE !=20 I used the chemist's definition of stoichiometricly correct (sic) - = which is when all of the (active) elements are combined (my italics) to = produce a compound=20 In a word BULLSHIT ! There is no single compound produced and stoich=20 does not apply to any branch of chemistry except combustion.=20 =20 mixture is the key word.=20 If I had a pound of fuel and 14.7 pounds of air at STP I would have a=20 stoichiometric mixture even if it was held in a balloon. Absolutely no = combustion is required for this condition it is a MOL. What happens = when you try to ignite it is a completely different field of study. = Combustion chemistry which I am sure you are familiar with has a = multiplicity of factors that affect the results only one of which is the = MIXTURE that is supplied to the combustion chamber.=20 Baffle them with accuracy and facts; that ought to do the job.=20 Phil=20 - ------=_NextPart_000_003E_01BF4291.0905A800 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
believe what you want to believe - I=20 asked
 
 
see:
htt= p://www.chemical-stoichiometry.net/Resource_Titlepage.htm
http= ://www.chem.ualberta.ca/~plambeck/che/course/p0304x.htm
http://= www.compusmart.ab.ca/plambeck/che/p101/p01172.htm
http:/= /www.chem.ualberta.ca/~plambeck/che/p101/p01035.htm
http://= www.compusmart.ab.ca/plambeck/che/p101/p01033.htm
htt= p://www.chemical-stoichiometry.net/Tutorial_Titlepage.htm
http://www.chemical-stoic= hiometry.net/
http://www.c= hemical-stoichiometry.net/tutorial.html
http://www.collingwood.org/chemistry/Curriculum%20Docs/ch1111.htm
http:= //www.chem.ualberta.ca/~plambeck/che/struct/s0201.htm
http://w= ww.chemical-stoichiometry.net/begin_student.htm
htt= p://www.compusmart.ab.ca/plambeck/che/course/vn41505x.htm
http:/= /www.chem.ualberta.ca/~plambeck/che/p102/p0511x.htm
and
htt= p://www.chem.ualberta.ca/courses/plambeck/p102/p02085.htm
 
to start with.
Says if anybody is full of BS it's not = me.=20 Stoiciometry in many points of reference - other than = combustion.
An excerpt from the last = reference:
 
Stoichiometric calculations involving = redox=20 reactions always begin with the balanced redox reaction. Once the = balanced redox=20 reaction has been obtained, the mole ratios will give the desired = stoichiometric=20 information. .............
 
Combustion is a Redox reaction =20 (oxidation/reduction)
I've been told to make sure I've got my = facts=20 straight before posting "opinions" - the definition I gave may be a = gross=20 simplification - but the facts are the facts.
 
Now, as for stoich being a moving = target - A=20 theoretically stoich mixture may not behave as stoich under certain = conditions -=20 something to do with elemental vs radical oxygen - elemental oxygen is = not as=20 reactive as radical oxygen, so if the O2 can be dissassociated into 2 X = O, and=20 the Hydrogen and Oxygen of the hydrocarbon fuel dissaciated into = hydrogen and=20 carbon, the reactions of oxygen + carbon =3D carbon dioxide, and = hydrogen +=20 oxygen=3Dwater can become stoichiometrically correct, Changing the = reaction of=20 nitrogen + oxygen=3Dnitous oxides (or oxides of nitogen - NOX) in the = cyl can and=20 does change the stoichiometry of the reaction in the cyl. This is, in = effect,=20 what EGR does to an engine. By inhibiting the formation of NOX the = actual=20 mixture ratio of gasoline and air required can be can be changed. = Decrease NOX=20 production and the mixture required for a stoichiometrically correct = combustion=20 of the fuel can be richened because more oxygen is available for the = desired=20 reaction.
 
 
----- Original Message -----
From:=20 Phil = Lamovie
Sent: Thursday, December 09, = 1999 10:02=20 AM
Subject: Stoich

 
 =20

Hi Clare,=20

Stoich is a point that moves with conditions ?=20

ABSOLUTELY IMPOSSIBLE !=20

is the mixture required to convert ALL of 2 elements to a compound=20

TRUE !=20

I used the chemist's definition of stoichiometricly correct (sic) - = which=20 is when all of the (active) elements are combined  = (my=20 italics) to produce a compound=20

In a word  BULLSHIT ! There is no single compound produced and = stoich=20
does not apply to any branch of chemistry except combustion. =
 =20

mixture is the key word.=20

If I had a pound of fuel and 14.7 pounds of air at STP I would have = a=20
stoichiometric mixture even if it was held in a balloon. = Absolutely no=20
combustion is required for this condition it is a MOL. What = happens when=20 you try to ignite it is a completely different field of study. = Combustion=20 chemistry which I am sure you are familiar with has a multiplicity of = factors=20 that affect the results only one of which is the MIXTURE that is = supplied to=20 the combustion chamber.=20

Baffle them with accuracy and facts; that ought to do the job.=20

Phil

- ------=_NextPart_000_003E_01BF4291.0905A800-- ------------------------------ Date: Fri, 10 Dec 1999 02:48:07 EST From: PHXSYS@xxx.com Subject: Sample HC11 EFI code in C Hi Can anyone hook me up with some sample starter HC11 EFI code in C to get me started on a project? The more samples the better. I found some in asm, but I want to understand the strategy. I found some in c for the 332, but that pretty sophisticated and difficult to understand. Thanks in advance Jon ------------------------------ Date: Fri, 10 Dec 1999 02:52:23 EST From: PHXSYS@xxx.com Subject: Atmel 8535 for engine controller Hi Has anyone looked at using the Atmel AVR 8535 8 bit micro for an engine controller? It has 8k flash, 512 bytes eeprom, 8 ch 10 bit a/d, pwm, capture/compare, usart, spi, 3 timers...Cost about 7-8$ ? Advantages and disadvantages over hc11? Thanks Jon ------------------------------ End of DIY_EFI Digest V4 #687 ***************************** To subscribe to DIY_EFI-Digest, send the command: subscribe diy_efi-digest in the body of a message to "Majordomo@xxx. A non-digest (direct mail) version of this list is also available; to subscribe to that instead, replace "diy_efi-digest" in the command above with "diy_efi".