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JOHNBOY
June 5th, 2014, 01:44 PM
I have never had good results with logging EGTs. So I decided to scrap the old approach. I bought an AEM 30-5131 gage. It out puts a 5v signal that can be easily logged with external inputs on the V2. So far it is working great! My question is how do I write a custom pid to change the volts to Degrees F on my dash?
The scale is 0* = .5v and 1800* = 4.5v.

More info here. http://aemelectronics.com/files/instructions/30-5131%20Analog%20EGT%20SAE%20Gauge.pdf

Thanks

5.7ute
June 5th, 2014, 02:19 PM
Should be simple since it is a linear output.
( EXT.ADn-0.5)*450

darcy
June 5th, 2014, 03:00 PM
See page 5 of the manual that you've posted for the formulae.

For Temp in F* : {EXT.AD1} * 450 -225
For Temp in C* : {EXT.AD1} * 250 -143

JOHNBOY
June 5th, 2014, 08:37 PM
Thanks guys!

It was right there in front of me. LOL

joecar
June 6th, 2014, 02:34 AM
You should be able to modify your current pid (with the above formulae) so that the one pid produces both *C and *F.

JOHNBOY
June 9th, 2014, 01:02 AM
I have not had a chance to alter the pid yet. Just referencing the voltage to the chart. Working great. To pulls with flawless EGT monitoring!
Very please with the AEM hardware so far.

JOHNBOY
June 9th, 2014, 12:33 PM
OK not having much luck with creating the pid

I keep getting error
Error code: ERR_DUPLICATE/109

Duplicate *UNITS: F.



What am missing?


# ================================================== ============================
# File details
# ------------
#
# This section defines various details about the file format.

*FILE

#Parameter Value Description
#---------- ---------------- ---------------------------------------------------
VERSION 7.1.1 File version
DECSEP . Decimal separator used in this file



# ================================================== ============================
# Units
# -------------------
# See sae_generic.txt for more information on the *UNITS section

*UNITS

#Code System Abbr Description
#-------- ---------- -------- -------------------------------------------------------------
F Imperial °F "Degrees Fahrenheit"



# ================================================== ============================
# Add slot definitions here
# --------------------------------
# See sae_generic.txt for more information on "SLOT" formats
#
#Units Low High Fmt Expression
#------------ ------------- ------------- ---- --------------------------------------------------------------
*CLC-00-002
F 0 1800 .1 "{EXT.AD1} * 450 -225"


# ================================================== ============================
*PRN - Parameter Reference Numbers
# --------------------------------
# See sae_generic.txt for more information on the *PRN section
#
#Code PRN SLOT Units System Description
#------------------------- ---- ------------ ---------------- ---------------- ------------------------------------
------

CALC.AEM_EGT F066 CLC-00-002 °F Temperature "AEM EGT"

JOHNBOY
June 9th, 2014, 12:40 PM
16962

darcy
June 9th, 2014, 12:52 PM
Try putting the °F in inverted commas in both locations. ie "°F"

joecar
June 9th, 2014, 12:53 PM
°F units already exist (as F), so delete your definition of it.

joecar
June 9th, 2014, 01:04 PM
*CLC-00-002
F 0 1800 .1 "{EXT.AD1} * 450 - 225"
C 0 1000 .1 "{EXT.AD1} * 250 - 142.8"




CALC.AEM_EGT F066 CLC-00-002 "F,C" Temperature "AEM EGT"

JOHNBOY
June 10th, 2014, 09:17 AM
OK It works great now. I screwed something up in the Calc_pid file. So I started fresh and it works as long as I leave out the defintions.
Thanks for all the help!

Any way here it is16969

joecar
June 10th, 2014, 09:36 AM
Also, make sure there are 2 blank lines at the end of the calc_pids.txt file (i.e. after all the text).

JOHNBOY
June 10th, 2014, 11:21 AM
Thanks for your help Joe!

joecar
June 10th, 2014, 11:38 AM
no worries :cheers: