Pages: 1 ... 7 8 [9] 10 11 12
Author Topic: Logging Zeitronix AFR with ME7L  (Read 184742 times)
nyet
Administrator
Hero Member
*****

Karma: +607/-168
Offline Offline

Posts: 12270


WWW
« Reply #120 on: April 11, 2014, 09:43:37 AM »

sounds like their output impedance isn't low enough (i.e. can't drive low loads).. dd are you using yours to drive your ecu inputs directly like julex is?
Logged

ME7.1 tuning guide
ECUx Plot
ME7Sum checksum
Trim heatmap tool

Please do not ask me for tunes. I'm here to help people make their own.

Do not PM me technical questions! Please, ask all questions on the forums! Doing so will ensure the next person with the same issue gets the opportunity to learn from your ex
ddillenger
Hero Member
*****

Karma: +641/-21
Offline Offline

Posts: 5640


« Reply #121 on: April 11, 2014, 10:18:09 AM »

Signal to black o2 wire, power and ground from chassis.
Logged

Please, ask all questions on the forums! Doing so will ensure the next person with the same issue gets the opportunity to learn from your experience!

Email/Google chat:
DDillenger84(at)gmail(dot)com

Email>PM
julex
Hero Member
*****

Karma: +79/-4
Offline Offline

Posts: 923


« Reply #122 on: April 11, 2014, 11:36:38 AM »

Signal to black o2 wire, power and ground from chassis.

Have you for a fact verified that you see 5V/20.00AFR on decel and expected 14.7AFR using 10+2*V formula at idle, which would be roughly 2.35V?

Logged
ddillenger
Hero Member
*****

Karma: +641/-21
Offline Offline

Posts: 5640


« Reply #123 on: April 11, 2014, 12:03:01 PM »

I am getting 18.9 on decel, not quite 5v but that is my fault.

As for there CS, it is utter shit, I agree.
Logged

Please, ask all questions on the forums! Doing so will ensure the next person with the same issue gets the opportunity to learn from your experience!

Email/Google chat:
DDillenger84(at)gmail(dot)com

Email>PM
savages4
Sr. Member
****

Karma: +10/-5
Offline Offline

Posts: 251


« Reply #124 on: April 11, 2014, 01:33:51 PM »

Yeah spartan works great for me... I haven't logged decel though to be honest.. and I don't have a gauge hooked up to it just logging.
Logged
julex
Hero Member
*****

Karma: +79/-4
Offline Offline

Posts: 923


« Reply #125 on: April 11, 2014, 04:36:12 PM »

I am getting 18.9 on decel, not quite 5v but that is my fault.

As for there CS, it is utter shit, I agree.

That's actually exactly what 4.424V or whereabouts would read in AFR: 4.424V * 2 = 8.848 + 10 = 18.848... so their product is not designed properly and it is not just a defective unit I have. What does it read at idle? Mince does around 2.05V which equals to around 14.1 using default scaling.

Logged
AARDQ
Sr. Member
****

Karma: +11/-0
Offline Offline

Posts: 338


« Reply #126 on: April 11, 2014, 04:46:57 PM »

That's actually exactly what 4.424V or whereabouts would read in AFR: 4.424V * 2 = 8.848 + 10 = 18.848... so their product is not designed properly and it is not just a defective unit I have. What does it read at idle? Mince does around 2.05V which equals to around 14.1 using default scaling.



Same here, 14.1 at switching and 18.9 at coast, wired into the ECU.  Timely thread; was just starting to hunt this down.
Logged
julex
Hero Member
*****

Karma: +79/-4
Offline Offline

Posts: 923


« Reply #127 on: April 14, 2014, 07:56:56 AM »

I have the values down in my logger but no access to the box right now, I will post the values sometime soon.
Logged
savages4
Sr. Member
****

Karma: +10/-5
Offline Offline

Posts: 251


« Reply #128 on: April 14, 2014, 08:45:01 PM »

I use mine alot, so you are saying its just not accurate with the conversion factors provided in this thread?  I hope this is not the case as my tune is quite dialed in now based off me thinking the wideband was accurate lol.
Logged
savages4
Sr. Member
****

Karma: +10/-5
Offline Offline

Posts: 251


« Reply #129 on: April 14, 2014, 08:57:53 PM »

Yeah I just checked I never see above 18.9 in any of my logs, even the long 20 minute ones.  Shit.  I hope its accurate from 10-15 where it counts...
Logged
julex
Hero Member
*****

Karma: +79/-4
Offline Offline

Posts: 923


« Reply #130 on: April 15, 2014, 07:50:17 AM »

HEre are the factors for Spartan that will convert its narrower than expected voltage range to proper AFR/Lambda:

Code:
WB_AFR_b2                , {}                                , 0x381114,  2,  0x0000, {}     , 0, 0,         0.0112338149664641,	-9.9154, {WB_AFR_b2}
WB_Lambda_b2             , {}                                , 0x381114,  2,  0x0000, {}        , 0, 0,         0.000774745, -0.68382, {WB_Lambda_b2}

Change name/address as you need.

How did I come up with that? Here are my cliff notes:

Code:
;; Spartan I received seems to be defective. I measured 4.400V (averaged) at open air and 2.05V (averaged) at 14.7AFR and 0.053469 (averaged) 
;; at 10.00 AFR. It should give 5V at open air and zero at no air.
;;
;; Measured values with voltmeter when connected to ECU (when not connected to ECU it ouputs full 0-5v range - Spartan has some design flaw):
;;
;; Sartan ECU Physical AFR
;; 0.005 0.053469 10 (bag with propane)
;; ~2.05 14.7 (running engine with 1.00 lambda)
;; 5.000 4.400 20 (open air or decel)
;;
;;
;;
;; Curve finder (that's a software you can get for free to find fits for you data).
;; Used 10.00 and 20.00 AFR points as 0.00 and 10.00 respectively with their voltages (voltages obtained empirically by averaging across hundreds of cells):
;;
;; 0.053469 0
;; 2.050 4.7
;; 4.400 10
;;
;; Got linear equation: y = a + bx   ->   y = -0.0846 + 2.299 * x
;;
;; Calculated 4.7 AFR: 2.08V    (due to the software doing the best to fit not so linear curve, there is a little bit of deviation but nothing significant)
;;
;; Good enough!!!
;;
;; Me7 Logger:
;; Spartan is gimped in that it only measures from 0.053469 to 4.400 so it really provides 4.400 - 0.005346953 = 4.394653047V range.
;;
;;
;; Verify that CurveFinder equation makes sense for 0, 4.7 and 10 AFR (before offset):
;; y = -0.0846 + 2.299 * 0.053469 = 0.03AFR  - almost zero
;; y = -0.0846 + 2.299 * 2.050    = 4.63     - close enough, it osciallates a lot anyway when idling
;; y = -0.0846 + 2.299 * 4.400    = 10.031   - spot on
;;
;; Verification complete and the equation is a pretty good fit considering empirical nature of arriving at it.
;;
;; We can obtain ME7 factor in two ways... determining divider which will define ratio of nominal 5V to narrower voltage ECU sees which is 4.394653047V or
;; using the function's 2.29 * x factor, they should be equivalent...
;; O2 volt variable holds 1024 discrete values for 0-5v voltage level. Since O2 WB measures 10AFR difference in that range, then 10/1024= 0.009765625
;; for one 1 unit in variable. That's stock but you need this to understand where the 1024 comes from.
;;
;; 10 / (1024 / (5V/4.394653047V)) = 0.0112338149664641
;; 10 / (1024 / (2.29V/2V))        = 0.011181640625
;;
;; There is 0.46% (one is 1.0046 larger than the other) difference between the two, you can use either one without much difference in output.
;; At 12AFR the error between the two will be 0.01 (one hundreth!) AFR and we usually measure well below 12AFR anyway so actual AFR error will be even smaller.
;;
;; Grand finale!!!
;;
;; ME7Logger values for 0x381114/0x381116 for POS Spartan O2 meter:
;;   AFR
;;     Offset: 10 - 0.0846 = 9.9154
;;     Factor: 0.0112338149664641
;;     Final Values: 0.0112338149664641, -9.9154
;;   Lambda:
;;     Offset: 9.9154/14.5 = -0.68382
;;     Factor: 0.0112338149664641 / 14.5 = 0.000774745
;;     Final Values: 0.000774745, -0.68382

WB_AFR_b2                , {}                                , 0x381114,  2,  0x0000, {}     , 0, 0,         0.0112338149664641, -9.9154, {WB_AFR_b2}
WB_Lambda_b2             , {}                                , 0x381114,  2,  0x0000, {}        , 0, 0,         0.000774745, -0.68382, {WB_Lambda_b2}
WB_Volt_b2               , {}                                , 0x381114,  2,  0x0000, {V}       , 0, 0,         0.004883,      0, {WB_Volt_b2}
« Last Edit: April 15, 2014, 07:57:30 AM by julex » Logged
julex
Hero Member
*****

Karma: +79/-4
Offline Offline

Posts: 923


« Reply #131 on: April 15, 2014, 07:55:24 AM »

Yeah I just checked I never see above 18.9 in any of my logs, even the long 20 minute ones.  Shit.  I hope its accurate from 10-15 where it counts...

Of course it is not. ME7 logger shows richer than it really is with default conversion.
Logged
julex
Hero Member
*****

Karma: +79/-4
Offline Offline

Posts: 923


« Reply #132 on: April 18, 2014, 05:56:58 AM »

Alan replied to my report of unusual readings and I got this:

"Hi,

Send me unit back, I will give you a refund. Follow the instructions here, http://www.14point7.com/pages/warranty-process

Your ECU is putting too much load on the linear output, there is nothing I can do about it but to refund your purchase.
"

I am not sure what to do... For one, I was able to make it work but on the other hand I am afraid that one of these days it will burn due to overheating issues with mismatching impedances (ECU having lower impedance than what Spartan can do).

Logged
savages4
Sr. Member
****

Karma: +10/-5
Offline Offline

Posts: 251


« Reply #133 on: April 18, 2014, 03:34:59 PM »

That is super lame.  I think I will have to upgrade to a LC2 or something then I guess.
Logged
nyet
Administrator
Hero Member
*****

Karma: +607/-168
Offline Offline

Posts: 12270


WWW
« Reply #134 on: April 18, 2014, 04:09:55 PM »

Or find somebody to build an op-amp circuit for you Sad
Logged

ME7.1 tuning guide
ECUx Plot
ME7Sum checksum
Trim heatmap tool

Please do not ask me for tunes. I'm here to help people make their own.

Do not PM me technical questions! Please, ask all questions on the forums! Doing so will ensure the next person with the same issue gets the opportunity to learn from your ex
Pages: 1 ... 7 8 [9] 10 11 12
  Print  
 
Jump to:  

Powered by SMF 1.1.21 | SMF © 2015, Simple Machines Page created in 0.026 seconds with 18 queries. (Pretty URLs adds 0.001s, 0q)