Input temp/afr data repley

Discussion on Future Megajolt hardware / software upgrades.

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alfa boxer
Posts: 47
Joined: Tue Jun 05, 2007 2:50 pm
Location: LEEDS UK

Input temp/afr data repley

Post by alfa boxer »

Hi brent, will the temp/afr (input)reading be visable on the laptop sreen with the rest of the data? if it was in the corner of the screen that would be fantastic feature to have. Also during play back of data you could possibly pause the play back at any point to study alterations. Thanks lee

mlarj
Posts: 13
Joined: Fri Apr 11, 2008 5:58 am

Post by mlarj »

Also would there be triggerable events based on temperature? Would I need to fit an additional temperature sender or will I be able to use the o/e one?

alfa boxer
Posts: 47
Joined: Tue Jun 05, 2007 2:50 pm
Location: LEEDS UK

MEGAJOLT/LM1 DATA LOGGING

Post by alfa boxer »

Hi ,just been on to the lm1 forum and recieved some usefull info below,

LM1 you have 2 analog output, the stereo cable with nothing at the end,
you can program these 2 analog output with LM programer in a range that megajolt can read. and these output a nicely linear
A common exemple is OV for 20AFR to 5V for 10AFR then log it .sounds really good :D

brentp
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Post by brentp »

Yes, logging will be available in the software.

The temp sensor input will accept a common resistive element (thermistor). The sensor calibration table will be configurable, but will default to support a common element, probably the GM element.

The circuit can be altered easily to accept a 0-5v input as well, which can be mapped similarly in the firmware.
Brent Picasso
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magicecu
Posts: 20
Joined: Thu Jan 01, 2009 7:05 pm

Aux input reverse voltage

Post by magicecu »

Hi i have fitted a coolant temperature sensor to a V4 and i`am receiving a higher reading when the water cools . How can i change the voltages around in the AUX INPUT CHANNEL OPTIONS so i can keep the gauge scaling aspect the same , left to right?

Patriq
Posts: 161
Joined: Sat May 26, 2007 12:56 pm
Location: Oslo, Norway

Re: Aux input reverse voltage

Post by Patriq »

magicecu wrote:Hi i have fitted a coolant temperature sensor to a V4 and i`am receiving a higher reading when the water cools . How can i change the voltages around in the AUX INPUT CHANNEL OPTIONS so i can keep the gauge scaling aspect the same , left to right?
In the configurator go to 'auxiliary input options' under 'tools'
There you can enter the desired value for each bin and each voltage reading from your sensor. Or just a scaling factor.
You can also read a bit more in this thread were I've been discussing a similar matter regarding the V3 MJLJ.

http://www.autosportlabs.org/viewtopic.php?t=2100
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brentp
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Post by brentp »

Also see here in the documentation:

http://www.autosportlabs.net/MJLJ_V4_Op ... figuration
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magicecu
Posts: 20
Joined: Thu Jan 01, 2009 7:05 pm

Aux Input Sensor

Post by magicecu »

Hi thanks alot for your help but i think for the moment its more for the scaling side to do perhaps later, in the mean time i have decided to get a GM#12146312 sensor, the one advertised in the MJLJ V4 Installation Guide. A PTC sensor and not a NTC sensor, just a bit of tapping to do. All done and working apart from trigger sensor positioning on a 1.8 K-series but only as a backup ECU until i have got the mapping side figured.

magicecu
Posts: 20
Joined: Thu Jan 01, 2009 7:05 pm

PTC or NTC

Post by magicecu »

Hi can any one tell me whether the coolant temperature sensor used for the AUX Input has to be a PTC to work with the default voltage scaling, and is this what the sensor described as for example in the Vehicle Installation Guide GM 12146312 ?
Attachments
Mjlj_v4_aux_in_temp_sensor_pinout.png
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Last edited by magicecu on Fri Jun 26, 2009 9:37 pm, edited 1 time in total.

Patriq
Posts: 161
Joined: Sat May 26, 2007 12:56 pm
Location: Oslo, Norway

Re: PTC or NTC

Post by Patriq »

magicecu wrote:Hi can any one tell me whether the coolant temperature sensor used for the AUX Input has to be a PTC to work with the default voltage scaling ADC, and is this what the sensor described as for example in the Vehicle Installation Guide GM 12146312 ?
What is PTC ?
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magicecu
Posts: 20
Joined: Thu Jan 01, 2009 7:05 pm

Positive temperature coefficent

Post by magicecu »

If the thermistor temperature sensor causes the ohms to rise and the voltage at the same time when it is heated it is a PTC thermistor and that is what relates to the V4 software AUX input scale, i have an equvalant sensor to the advertised one ,a direct replacement but the ohms go down when heated. I will probably give it some more checks.

NITROPIXIE
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Location: Fareham, GB

Post by NITROPIXIE »

ptc - positive temperature coefficent - resistance increases with temperature

Also

ntc - negative temperature coefficent - resistance decreases with temperature - these areprobably more common in day to day life
1310 A-series Mini, lightened and built myself. V4 board and loving it

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magicecu
Posts: 20
Joined: Thu Jan 01, 2009 7:05 pm

Temperature gauge now working on auxilary input

Post by magicecu »

I was able to get this working by changing the 'Load Axis Calibration' Scaled Value round and saving and writing to the MJJL the read values, by using the saved base map.

NITROPIXIE
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Location: Fareham, GB

Post by NITROPIXIE »

Sweet, good to hear you got it sorted.
1310 A-series Mini, lightened and built myself. V4 board and loving it

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mark pietz
Posts: 29
Joined: Mon Aug 03, 2009 12:56 am

Wideband sensor

Post by mark pietz »

This may be heresy but now that I have gotten my IH up and running (and past/passed smog) I have my Megajolt/EDIS ignition reinstalled and operational. Working out the ignition table in the n/a mode, but soon the turbo goes on. Here are my needs: Since I want to run an a/f gauge to work out the weird carb jetting issues I'll be having (as well as on my dash), that means a sideband 02 sensor. Can I run a simple sensor like the innovate lc-1 (or is it lc-2) and simply use that analog 0-5v output into my auxiliary input (cutting that R6 trace) and then it would provide the data log voltage trace along with the other data?

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