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| How do I interpret MAP Sensor raw ECM values as vacuum and pressure. (Page 1/1) |
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Romsk
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AUG 21, 06:30 PM
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Does anyone have any info on how to convert MAP raw values read from the ALDL data stream into vaccum and pressure?
I don't have a tool that can "create" vaccum or pressure. I can "measure" vaccum and pressure at the MAP with the engine running and such, but it changes so much I can't get a good correlation between what the MAP sees moment to moment and how the ECM interprets it.
If not, is anyone curious (and ambitious) to connect a vaccum/pressure generator to the vaccum input of their MAP, set the ALDL to ALDL Mode (10 kOhms), put the Ignition On but not run the engine, and get various raw MAP variable data values from the ALDL (0 to 255) for various vaccums and pressures put on the MAP sensor?
I don't care if vaccum and pressure is in inHg, mmHg, Bar, or PSI.
10 data points should do it. I can interpolate the rest for the full range of 0 to 255.
The actual raw values don't have to be spot on per my suggestions below (each can be off by a few counts) as long as we can get a 10 point wide spread in the 0 to 255 range and fairly accurate pressure/vaccum readings for the each raw value measured.
code:
Raw MAP Variable from the ECM Vaccum/Pressure Applied to the MAP sensor input port
5 ?
10 ?
50 ?
75 ?
100 ?
125 ?
150 ?
175 ?
200 ?
250 ?
Thanks.
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Paul Romsky[This message has been edited by Romsk (edited 08-21-2022).]
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theogre
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AUG 21, 08:48 PM
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U don't. Vacuum doesn't exist to anything but people reading a Vacuum Gauge with "Fake" Zero somewhere on the scale that just means not connected or whatever is not on.
MAP count Up, 0 to 5v on output pin, from a "Total" Vacuum. See my Cave, Sensors Quick Ref @ bottom.
GM et al use 1 Bar units for all non-boosted engines.
Most Super or Turbo uses 2 or 3 Bar units, if they use a MAP at all, but they still work with 0 to 5v and program ECM/PCM for scaling 1 2 3 or more Bars...
1 Bar units only sees "vacuum" w/ engine running as you read on a normal Vac Gauge you buy but to the MAP viewpoint only sees and measure pressure from True Zero.
2 or more can see whatever boost when active.
ECM/PCM can use them as a barometer before start the engine to test local weather/altitude to set a base timing and fuel map. So will start and run at the beach or in high altitude cities.
All OE and aftermarket ECM/PCM using MAP does the same to program to control the engine and transmission for PCM to set shift points etc.------------------
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)
The Ogre's Fiero Cave
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Romsk
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AUG 21, 09:56 PM
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theogre,
You are a well of knowledge! Thanks. That is a great page you have! I am going to study it some more.
Just be sure we are on the same page...
Vacuum means two things to me: Absolute Vaccum based on a scale starting from 0, or relative pressure changes where a reduction in pressure from ambient pressure is a "vacuum" (like in the intake manifold) and increases (negative vacuum) above ambient pressure, that is "pressure" as opposed to vacuum in this sense (say in a boosted intake manifold). Either way, they translate to some PSIA value.
So those voltages out of the MAP do translate to A/D counts in the ECM which are reported by the ALDL.
Various Absolute Pressures = Various Voltages = Various A/D values in the ECM = Various Values reported as the MAP Variable in the ALDL data stream.
That is what I am trying to determine over the full dynamic range of the MAP sensor and ALDL.
Yes, I figured that the initial reading before the engine is started is the current atmospheric pressure which on the absolute scale is about 14.7 PSIA (Yes, 0 = pure vaccum - there is actually nowhere in free space where PSIA is true 0.0 even in intergalactic space, there are still a few molecules per cubic meter and thus a pressure in micro Torr. Ok, we are nowhere near those levels [whew!]
From your page, the voltage when at 14.7 PSIA gives me one data point in the ALDL data range of 0 to 255. I just need to get a few more data points to correlate other PSIA pressures to ALDL values. For example, when the engine revs, vacuum will be introduced in the intake manifold. So, say, a 10 inHg of vacuum = a drop of about 1.7V from the MAP = something less than 14.7 PSIA. This new lower absolute pressure is converted to a lower voltage by the MAP sensor, and the ECM converts this voltage to a value different from the initial reading (but still somewhere between 0 and 255, but to what value?).
So what I need is to know is when the pressure drops by 10 inHg, what value does the ECM report.
And say for several further drops of about 10 inHg each until its at a level not practically experienced in the manifold or the MAP sensor minimums out.
And why not go the other way for increases in pressure of about 10 inHg - to report pressures above 14.7 PSIA which is not normal in a non-boosted engines (like mine, correct?)..
but good to know if it happens.
If I could make something that can "statically stable" put various calibrated levels of vacuum, that is pressures below 14.7 PSIA into the MAP sensor (pressures of > 0 PSIA but less than ambient PSIA of about 14.7) of say in 10 inHg steps down, then I can correlate those absolute pressures to ALDL values reported.
That is crux of my investigation.
Any ideas? Money is an issue here. My CFO (wife) has given me a budget of $0. [laugh]
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Paul Romsky[This message has been edited by Romsk (edited 08-21-2022).]
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theogre
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AUG 22, 01:04 AM
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Read page again...
test volts, "pull 10in vac," test volts
GM etc never say a starting volts because Your starting volts changes for weather and altitude.
Same if you pull a vac at whatever steps to the max and check volts for each step.
Then weather, altitude or both changes but your program only use same volts and engine run bad or not at all.
That's why GM etc use MAP as barometer first.
IOW if you drive from beach near Sea Level to just Binghamton NY pushing 1000 feet altitude w/o shut down anywhere older ECM/PCM may have problems because still think is at sea level to set timing etc. Worse if drive to Boulder CO and even higher cities. (just ignore most can't on a single tank...)
New cars could use "extra MAP" built into PCM to read altitude when engine is on. Don't know if they do or not but easy and cheap now w/ many surface mount sensors available.
Now if you use MAP for weather and other things... Much Better sensors for this and libraries for use w/ Pi, Arduino, etc. Go look at the libraries how they convert x output to a pressure that means something. Problem is likely most are digital and GM MAP isn't.
Might find a library for GM MAP because so very common anyway. Would simply go to A/D port on 5v Arduino etc. and library convert MAP, pretend Vac/pressure Gauge, or whatever. Good luck find that because MAP() is a function of most program languishes.
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Romsk
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AUG 22, 08:41 AM
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I think I have a solution:
I do have a cheezy $10 Harbour Frieght Manifold Vacuum/Fuel Pressure guage. It's not very accurate but it will do.
I can draw a vacuum up to 20 inHg using my mouth and my tongue on the hose as a "ratcheting" technique to get and hold just about any I pressure (vaccum) I need.
My experiment:
Ignition On, Engine Not Running.
First I disconnect the MAP Sensor line to the manifold and connect the MAP Sensor to a Tee and my Guage.
code:
MAP <-> Tee <-> Gauge
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V
My Mouth
Then, I look on-line and get the local barometric pressure in inHg and record the voltage (0 to 5V with millivolts resolution) out of the MAP Sensor.
Then I put 5 inHg vaccum on the Tee using my mouth/tongue technique, and measure the voltage out of the MAP Sensor.
I repeat and record vaccums and voltages in 5 inHg steps until I read near 0V from the MAP Sensor.
Then I go the other way and apply pressure above ambient by blowing into the Tee in 5 inHg steps until I read near 5V from the MAP Sensor.
Now I will have a good pressure response vs voltage of the MAP Sensor through its full dynamic range.
Then, I can put a 10kOhm potentiometer across the 3 pins of the MAP Sensor connector that goes to the ECM (disconnected from the MAP Sensor), and dial in each voltage and record the raw ALDL values (0 to 255) of the MAP Variable for each.
Then I will have a good pressure response vs ALDL raw values.
The rest is academic... I curve fit the response so I can create a transfer function to now display the raw ALDL values as a more meaningful absolute pressure in inHg or mmHg from the MAP Sensor.
I will do that later today and post my results.[This message has been edited by Romsk (edited 08-22-2022).]
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Romsk
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AUG 22, 03:13 PM
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Ok, I now have an equation to convert Raw MAP Sensor ALDL values to inHg Abs.
code:
Fiero MAP Sensor to ALDL Raw Data to Absolute Pressure in inHg Curve Fit Analysis
Paul Romsky: 22 AUG 2022 05:52 UTC
PolyFit Status = 0
PolyFit Description : The call was successful.
Samples = 5
Order = 3
Sample[0] = 246 A/D Count 30.140 inHg Abs 4.830 Volts (Ambient Atmospheric Pressure in Hollis, NH, USA on 22 AUG 2022 at 04:22 UTC)
Sample[1] = 197 A/D Count 25.140 inHg Abs 3.870 Volts
Sample[2] = 151 A/D Count 20.140 inHg Abs 2.954 Volts
Sample[3] = 105 A/D Count 15.140 inHg Abs 2.050 Volts
Sample[4] = 60 A/D Count 10.140 inHg Abs 1.180 Volts
Polynomial_Value[0] = 30.145267671
Polynomial_Value[1] = 25.117363566
Polynomial_Value[2] = 20.175155207
Polynomial_Value[3] = 15.116050688
Polynomial_Value[4] = 10.146162869
Coefficient[0] = 3.64429395552267321178874226461630
Coefficient[1] = 0.10614031967576748050063883965777
Coefficient[2] = 0.00004694591003016911935630250952
Coefficient[3] = -0.00000016460899788811870803366053
Mean_Squared_Error = 0.00047751911456259674756269495433
Equation: inHg Abs = Coefficient[0] + (Coefficient[1] * A/D_Count) + (Coefficient[2] * pow(A/D_Count, 2)) +
(Coefficient[3] * pow(A/D_Count, 3))
X = 0 A/D Count Y = 3.644 inHg Abs
X = 1 A/D Count Y = 3.750 inHg Abs
X = 2 A/D Count Y = 3.857 inHg Abs
X = 3 A/D Count Y = 3.963 inHg Abs
X = 4 A/D Count Y = 4.070 inHg Abs
X = 5 A/D Count Y = 4.176 inHg Abs
X = 6 A/D Count Y = 4.283 inHg Abs
X = 7 A/D Count Y = 4.390 inHg Abs
X = 8 A/D Count Y = 4.496 inHg Abs
X = 9 A/D Count Y = 4.603 inHg Abs
X = 10 A/D Count Y = 4.710 inHg Abs
X = 11 A/D Count Y = 4.817 inHg Abs
X = 12 A/D Count Y = 4.924 inHg Abs
X = 13 A/D Count Y = 5.032 inHg Abs
X = 14 A/D Count Y = 5.139 inHg Abs
X = 15 A/D Count Y = 5.246 inHg Abs
X = 16 A/D Count Y = 5.354 inHg Abs
X = 17 A/D Count Y = 5.461 inHg Abs
X = 18 A/D Count Y = 5.569 inHg Abs
X = 19 A/D Count Y = 5.677 inHg Abs
X = 20 A/D Count Y = 5.785 inHg Abs
X = 21 A/D Count Y = 5.892 inHg Abs
X = 22 A/D Count Y = 6.000 inHg Abs
X = 23 A/D Count Y = 6.108 inHg Abs
X = 24 A/D Count Y = 6.216 inHg Abs
X = 25 A/D Count Y = 6.325 inHg Abs
X = 26 A/D Count Y = 6.433 inHg Abs
X = 27 A/D Count Y = 6.541 inHg Abs
X = 28 A/D Count Y = 6.649 inHg Abs
X = 29 A/D Count Y = 6.758 inHg Abs
X = 30 A/D Count Y = 6.866 inHg Abs
X = 31 A/D Count Y = 6.975 inHg Abs
X = 32 A/D Count Y = 7.083 inHg Abs
X = 33 A/D Count Y = 7.192 inHg Abs
X = 34 A/D Count Y = 7.301 inHg Abs
X = 35 A/D Count Y = 7.410 inHg Abs
X = 36 A/D Count Y = 7.519 inHg Abs
X = 37 A/D Count Y = 7.627 inHg Abs
X = 38 A/D Count Y = 7.736 inHg Abs
X = 39 A/D Count Y = 7.845 inHg Abs
X = 40 A/D Count Y = 7.954 inHg Abs
X = 41 A/D Count Y = 8.064 inHg Abs
X = 42 A/D Count Y = 8.173 inHg Abs
X = 43 A/D Count Y = 8.282 inHg Abs
X = 44 A/D Count Y = 8.391 inHg Abs
X = 45 A/D Count Y = 8.501 inHg Abs
X = 46 A/D Count Y = 8.610 inHg Abs
X = 47 A/D Count Y = 8.720 inHg Abs
X = 48 A/D Count Y = 8.829 inHg Abs
X = 49 A/D Count Y = 8.939 inHg Abs
X = 50 A/D Count Y = 9.048 inHg Abs
X = 51 A/D Count Y = 9.158 inHg Abs
X = 52 A/D Count Y = 9.267 inHg Abs
X = 53 A/D Count Y = 9.377 inHg Abs
X = 54 A/D Count Y = 9.487 inHg Abs
X = 55 A/D Count Y = 9.597 inHg Abs
X = 56 A/D Count Y = 9.706 inHg Abs
X = 57 A/D Count Y = 9.816 inHg Abs
X = 58 A/D Count Y = 9.926 inHg Abs
X = 59 A/D Count Y = 10.036 inHg Abs
X = 60 A/D Count Y = 10.146 inHg Abs
X = 61 A/D Count Y = 10.256 inHg Abs
X = 62 A/D Count Y = 10.366 inHg Abs
X = 63 A/D Count Y = 10.476 inHg Abs
X = 64 A/D Count Y = 10.586 inHg Abs
X = 65 A/D Count Y = 10.697 inHg Abs
X = 66 A/D Count Y = 10.807 inHg Abs
X = 67 A/D Count Y = 10.917 inHg Abs
X = 68 A/D Count Y = 11.027 inHg Abs
X = 69 A/D Count Y = 11.137 inHg Abs
X = 70 A/D Count Y = 11.248 inHg Abs
X = 71 A/D Count Y = 11.358 inHg Abs
X = 72 A/D Count Y = 11.468 inHg Abs
X = 73 A/D Count Y = 11.579 inHg Abs
X = 74 A/D Count Y = 11.689 inHg Abs
X = 75 A/D Count Y = 11.799 inHg Abs
X = 76 A/D Count Y = 11.910 inHg Abs
X = 77 A/D Count Y = 12.020 inHg Abs
X = 78 A/D Count Y = 12.131 inHg Abs
X = 79 A/D Count Y = 12.241 inHg Abs
X = 80 A/D Count Y = 12.352 inHg Abs
X = 81 A/D Count Y = 12.462 inHg Abs
X = 82 A/D Count Y = 12.573 inHg Abs
X = 83 A/D Count Y = 12.683 inHg Abs
X = 84 A/D Count Y = 12.794 inHg Abs
X = 85 A/D Count Y = 12.904 inHg Abs
X = 86 A/D Count Y = 13.015 inHg Abs
X = 87 A/D Count Y = 13.125 inHg Abs
X = 88 A/D Count Y = 13.236 inHg Abs
X = 89 A/D Count Y = 13.347 inHg Abs
X = 90 A/D Count Y = 13.457 inHg Abs
X = 91 A/D Count Y = 13.568 inHg Abs
X = 92 A/D Count Y = 13.678 inHg Abs
X = 93 A/D Count Y = 13.789 inHg Abs
X = 94 A/D Count Y = 13.900 inHg Abs
X = 95 A/D Count Y = 14.010 inHg Abs
X = 96 A/D Count Y = 14.121 inHg Abs
X = 97 A/D Count Y = 14.231 inHg Abs
X = 98 A/D Count Y = 14.342 inHg Abs
X = 99 A/D Count Y = 14.453 inHg Abs
X = 100 A/D Count Y = 14.563 inHg Abs
X = 101 A/D Count Y = 14.674 inHg Abs
X = 102 A/D Count Y = 14.784 inHg Abs
X = 103 A/D Count Y = 14.895 inHg Abs
X = 104 A/D Count Y = 15.005 inHg Abs
X = 105 A/D Count Y = 15.116 inHg Abs
X = 106 A/D Count Y = 15.227 inHg Abs
X = 107 A/D Count Y = 15.337 inHg Abs
X = 108 A/D Count Y = 15.448 inHg Abs
X = 109 A/D Count Y = 15.558 inHg Abs
X = 110 A/D Count Y = 15.669 inHg Abs
X = 111 A/D Count Y = 15.779 inHg Abs
X = 112 A/D Count Y = 15.890 inHg Abs
X = 113 A/D Count Y = 16.000 inHg Abs
X = 114 A/D Count Y = 16.111 inHg Abs
X = 115 A/D Count Y = 16.221 inHg Abs
X = 116 A/D Count Y = 16.331 inHg Abs
X = 117 A/D Count Y = 16.442 inHg Abs
X = 118 A/D Count Y = 16.552 inHg Abs
X = 119 A/D Count Y = 16.662 inHg Abs
X = 120 A/D Count Y = 16.773 inHg Abs
X = 121 A/D Count Y = 16.883 inHg Abs
X = 122 A/D Count Y = 16.993 inHg Abs
X = 123 A/D Count Y = 17.103 inHg Abs
X = 124 A/D Count Y = 17.214 inHg Abs
X = 125 A/D Count Y = 17.324 inHg Abs
X = 126 A/D Count Y = 17.434 inHg Abs
X = 127 A/D Count Y = 17.544 inHg Abs
X = 128 A/D Count Y = 17.654 inHg Abs
X = 129 A/D Count Y = 17.764 inHg Abs
X = 130 A/D Count Y = 17.874 inHg Abs
X = 131 A/D Count Y = 17.984 inHg Abs
X = 132 A/D Count Y = 18.094 inHg Abs
X = 133 A/D Count Y = 18.204 inHg Abs
X = 134 A/D Count Y = 18.314 inHg Abs
X = 135 A/D Count Y = 18.424 inHg Abs
X = 136 A/D Count Y = 18.534 inHg Abs
X = 137 A/D Count Y = 18.643 inHg Abs
X = 138 A/D Count Y = 18.753 inHg Abs
X = 139 A/D Count Y = 18.863 inHg Abs
X = 140 A/D Count Y = 18.972 inHg Abs
X = 141 A/D Count Y = 19.082 inHg Abs
X = 142 A/D Count Y = 19.192 inHg Abs
X = 143 A/D Count Y = 19.301 inHg Abs
X = 144 A/D Count Y = 19.410 inHg Abs
X = 145 A/D Count Y = 19.520 inHg Abs
X = 146 A/D Count Y = 19.629 inHg Abs
X = 147 A/D Count Y = 19.738 inHg Abs
X = 148 A/D Count Y = 19.848 inHg Abs
X = 149 A/D Count Y = 19.957 inHg Abs
X = 150 A/D Count Y = 20.066 inHg Abs
X = 151 A/D Count Y = 20.175 inHg Abs
X = 152 A/D Count Y = 20.284 inHg Abs
X = 153 A/D Count Y = 20.393 inHg Abs
X = 154 A/D Count Y = 20.502 inHg Abs
X = 155 A/D Count Y = 20.611 inHg Abs
X = 156 A/D Count Y = 20.720 inHg Abs
X = 157 A/D Count Y = 20.828 inHg Abs
X = 158 A/D Count Y = 20.937 inHg Abs
X = 159 A/D Count Y = 21.046 inHg Abs
X = 160 A/D Count Y = 21.154 inHg Abs
X = 161 A/D Count Y = 21.263 inHg Abs
X = 162 A/D Count Y = 21.371 inHg Abs
X = 163 A/D Count Y = 21.480 inHg Abs
X = 164 A/D Count Y = 21.588 inHg Abs
X = 165 A/D Count Y = 21.696 inHg Abs
X = 166 A/D Count Y = 21.804 inHg Abs
X = 167 A/D Count Y = 21.912 inHg Abs
X = 168 A/D Count Y = 22.020 inHg Abs
X = 169 A/D Count Y = 22.128 inHg Abs
X = 170 A/D Count Y = 22.236 inHg Abs
X = 171 A/D Count Y = 22.344 inHg Abs
X = 172 A/D Count Y = 22.452 inHg Abs
X = 173 A/D Count Y = 22.559 inHg Abs
X = 174 A/D Count Y = 22.667 inHg Abs
X = 175 A/D Count Y = 22.774 inHg Abs
X = 176 A/D Count Y = 22.882 inHg Abs
X = 177 A/D Count Y = 22.989 inHg Abs
X = 178 A/D Count Y = 23.096 inHg Abs
X = 179 A/D Count Y = 23.204 inHg Abs
X = 180 A/D Count Y = 23.311 inHg Abs
X = 181 A/D Count Y = 23.418 inHg Abs
X = 182 A/D Count Y = 23.525 inHg Abs
X = 183 A/D Count Y = 23.631 inHg Abs
X = 184 A/D Count Y = 23.738 inHg Abs
X = 185 A/D Count Y = 23.845 inHg Abs
X = 186 A/D Count Y = 23.951 inHg Abs
X = 187 A/D Count Y = 24.058 inHg Abs
X = 188 A/D Count Y = 24.164 inHg Abs
X = 189 A/D Count Y = 24.270 inHg Abs
X = 190 A/D Count Y = 24.377 inHg Abs
X = 191 A/D Count Y = 24.483 inHg Abs
X = 192 A/D Count Y = 24.589 inHg Abs
X = 193 A/D Count Y = 24.695 inHg Abs
X = 194 A/D Count Y = 24.800 inHg Abs
X = 195 A/D Count Y = 24.906 inHg Abs
X = 196 A/D Count Y = 25.012 inHg Abs
X = 197 A/D Count Y = 25.117 inHg Abs
X = 198 A/D Count Y = 25.223 inHg Abs
X = 199 A/D Count Y = 25.328 inHg Abs
X = 200 A/D Count Y = 25.433 inHg Abs
X = 201 A/D Count Y = 25.538 inHg Abs
X = 202 A/D Count Y = 25.643 inHg Abs
X = 203 A/D Count Y = 25.748 inHg Abs
X = 204 A/D Count Y = 25.853 inHg Abs
X = 205 A/D Count Y = 25.958 inHg Abs
X = 206 A/D Count Y = 26.062 inHg Abs
X = 207 A/D Count Y = 26.167 inHg Abs
X = 208 A/D Count Y = 26.271 inHg Abs
X = 209 A/D Count Y = 26.375 inHg Abs
X = 210 A/D Count Y = 26.480 inHg Abs
X = 211 A/D Count Y = 26.584 inHg Abs
X = 212 A/D Count Y = 26.688 inHg Abs
X = 213 A/D Count Y = 26.791 inHg Abs
X = 214 A/D Count Y = 26.895 inHg Abs
X = 215 A/D Count Y = 26.999 inHg Abs
X = 216 A/D Count Y = 27.102 inHg Abs
X = 217 A/D Count Y = 27.205 inHg Abs
X = 218 A/D Count Y = 27.309 inHg Abs
X = 219 A/D Count Y = 27.412 inHg Abs
X = 220 A/D Count Y = 27.515 inHg Abs
X = 221 A/D Count Y = 27.617 inHg Abs
X = 222 A/D Count Y = 27.720 inHg Abs
X = 223 A/D Count Y = 27.823 inHg Abs
X = 224 A/D Count Y = 27.925 inHg Abs
X = 225 A/D Count Y = 28.028 inHg Abs
X = 226 A/D Count Y = 28.130 inHg Abs
X = 227 A/D Count Y = 28.232 inHg Abs
X = 228 A/D Count Y = 28.334 inHg Abs
X = 229 A/D Count Y = 28.436 inHg Abs
X = 230 A/D Count Y = 28.537 inHg Abs
X = 231 A/D Count Y = 28.639 inHg Abs
X = 232 A/D Count Y = 28.740 inHg Abs
X = 233 A/D Count Y = 28.841 inHg Abs
X = 234 A/D Count Y = 28.943 inHg Abs
X = 235 A/D Count Y = 29.044 inHg Abs
X = 236 A/D Count Y = 29.144 inHg Abs
X = 237 A/D Count Y = 29.245 inHg Abs
X = 238 A/D Count Y = 29.346 inHg Abs
X = 239 A/D Count Y = 29.446 inHg Abs
X = 240 A/D Count Y = 29.547 inHg Abs
X = 241 A/D Count Y = 29.647 inHg Abs
X = 242 A/D Count Y = 29.747 inHg Abs
X = 243 A/D Count Y = 29.847 inHg Abs
X = 244 A/D Count Y = 29.946 inHg Abs 29.921 inHg Abs (14.6959 PSIA) is average at Mean Sea Level (MSL)
X = 245 A/D Count Y = 30.046 inHg Abs
X = 246 A/D Count Y = 30.145 inHg Abs
X = 247 A/D Count Y = 30.245 inHg Abs
X = 248 A/D Count Y = 30.344 inHg Abs
X = 249 A/D Count Y = 30.443 inHg Abs
X = 250 A/D Count Y = 30.541 inHg Abs
X = 251 A/D Count Y = 30.640 inHg Abs
X = 252 A/D Count Y = 30.739 inHg Abs
X = 253 A/D Count Y = 30.837 inHg Abs
X = 254 A/D Count Y = 30.935 inHg Abs
X = 255 A/D Count Y = 31.033 inHg Abs
[This message has been edited by Romsk (edited 08-22-2022).]
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Romsk
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AUG 22, 03:22 PM
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<redundant post deleted> [This message has been edited by Romsk (edited 08-22-2022).]
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