Calc PID's for AD Input

[BlkMax]

How do I write these? I have seen others figure this out, and EFILive made one for me, but how do I do this myself?

I have some Aeroforce transmitters that read from 0-150 psi, and 0.5-4.5 VDC output.

How do I make a Calc-PID statement for these to read correctly when I input them into the analog inputs on a V2?

FWIW, the Aeroforce folks say to configure their gauge with an intercept of 37.5, and a slope of -18.7.

I am not looking for the metric units on this, just the imperial.

[mr.prick]

(Volts*Slope)+Intercept

[joecar]

What mr.prick said...

1: 0.5V = 0 psi = 0 kPa
2: 4.5V = 150 psi = 1034.2 kPa

Imperial:
slope = (p2 - p1)/(v2 - v1) = (150 - 0)/(4.5 - 0.5) = 37.5
intercept = p1- v1*slope = 0 - 0.5*37.5 = -18.75
so p = slope*v + intercept = 37.5*v - 18.75

Metric:
slope = (p2 - p1)/(v2- v1) = (1034.2 - 0)/(4.5 - 0.5) = 258.6
intercept = p1 - v1*slope = 0 - 0.5*258.6 = -129.3
so p = slope*v + intercept = 258.6*v - 129.3

See attached calc_pids.txt, copy it to My Documents\EFILive\V7.5\User Configuration.

When you select this pid on the pids tab, do rightclick->Imperial for psi.

[mr.prick]

Great service as always Joe.
Coincidentally, I made a spreadsheet for WBO2 expressions a few days ago.

[joecar]

Handy spreadsheet...

[BlkMax]

Thanx Guys....

Merry Christmas

[mr.prick]

I updated the spreadsheet to compare AFR/Lambda PID expression to {B3601}.

[joecar]

Thanks for the update...

My only comment is: now you divide instead of multiplying to arrive at the AFR (just like HPT do)...?

[mr.prick]

There are 2 pages.
I saved it with the HPT side open so when it opens that is what you see and
it was the first version too.
It's fixed now.

[joecar]

Ah, I see... (or rather I missed the tabs/pages ).