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PLM Analogue Linear Output 0-5v

PostPosted: Fri Aug 08, 2014 11:39 am
by driftshop
Hey Guys,

I use a Motec PLM w/NTK to tune all cars and the Autronic HSAFR-Bosch Sensor for the dyno. The Industrial Wideband senseor (actually a narrow band with wideband sim) is becoming obsolete, harder to find and expensive. I change them every year for accuracy. I came across this tutorial regarding updating your own Dyno Dynamics Analogue dyno with a proper wideband (LSU 4.2 / 9 / NTK L1H1) as long as you have the linear relationship between voltage and lambda.

Does anyone have a graph or screenshot of what the linear output is on the Motec PLM with the NTK Sensor? Or perhaps let me know what is required to define the linear output in the software?

Motec PLM Brochure: "The MoTeC PLM provides an differential Analog Voltage Output that may be connected to an Analog Meter or other measurement instrument such as a Data Logger or Chart Recorder. The output may be defined by the user to be linear or non-linear in relation to the measured units. The PLM also supports 1mbit CAN and RS232 data links to devices such as the MoTeC Dash/Logger for transmission of sensor and diagnostic data. Comprehensive diagnostic and status channels are provided for."


"This is the file. Go to DOS, get into the "dyno" directory, and type "edit", and you will get this. Note the Autronic values. First value is Voltage at Zero output, Next value is Voltage at Max output, third value is Scale. I persume this is a multiplier of the AFR. For exampe, the Autronic has a 0 to 30 scale. 30/14.57 = 2.06 (I assume DD uses the often quoted NTK spec for stoich as 14.57, since the number 'works' lol).

As an example, I used a FAST wideband whos output function is AFR=(V x 2.78) + 9.6. And Max output of 4.096V. That works out to 0 AFR at -3.543 Volts, and 20.987 AFR at max volts. 20.987/14.57=1.440 for new "Scale".

I tried then entering the new config values as -3.543 4.096 and 1.440."

Thank You all.


Re: PLM Analogue Linear Output 0-5v

PostPosted: Fri Aug 08, 2014 5:30 pm
by David Ferguson
Download and install the PLM Setup program. You can get the standard output tables from there -- or modify your PLM to produce whatever you want.

Re: PLM Analogue Linear Output 0-5v

PostPosted: Sat Aug 09, 2014 7:31 pm
by driftshop
Yep I managed to use LA V1 which goes up to 20 lambda and voila everything is working, but a few points off, I would say around 0.01-0.03 lambda off. the reading.

The update is super fast compared to the old setup ... absolutely amazing to get this this working considering Dyno Dynamics want $750 for an LSU 4.2 setup that's a re-branded haltech unit which is a re-branded USA made unit.

I figured since the calibration on the dyno is based on the NTK, then this will be in the ball park and it was!