oil temperature sensor for stock gauge and EMU?

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Olli.D
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Joined:Mon Sep 21, 2015 7:51 am
oil temperature sensor for stock gauge and EMU?

Post by Olli.D » Tue Jan 12, 2016 9:48 pm

I like tuo use the stock sensor, what is already connected with the stock gauge.
Over the bandwide 20-100 degrees, i can read 6 - 8 Volt.
The EMU software only allowes 0 - 5V. When i try to switch to 8V, it goes back to 5V max.
The resistance of the EMU input 1 is about 980KOhm. Is it ok, if i just take a resistor of same (test +/-) Ohm in row?
So i would read about 3-4 Volt...
The measurement of the original gauge seems not to be irritated, that works with ca. 250 Ohm.

Is that practicable, or would you recommend another way?

Cheers, Olli

RHD
Posts:537
Joined:Tue Oct 07, 2014 4:28 pm

Re: oil temperature sensor for stock gauge and EMU?

Post by RHD » Wed Jan 13, 2016 1:32 am

you may want to connect 2 resistors about 1k from the gauge Op in series to ground and connect the EMU to the join between the 2 resistors thus forming a voltage split. you can scale the range by altering the size of one of the resistors etc.

Karel
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Location:Czech Republic
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Re: oil temperature sensor for stock gauge and EMU?

Post by Karel » Wed Jan 13, 2016 9:22 pm

any resistence from sensor to ground will affect the reading ............ i dont recommend it
if ..... i would use much bigger resostros for voltage divider, like 10k and above

Olli.D
Posts:8
Joined:Mon Sep 21, 2015 7:51 am

Re: oil temperature sensor for stock gauge and EMU?

Post by Olli.D » Sun Jan 17, 2016 9:12 pm

It is tested out today.
One part of the voltage splitter is the EMU herself with about 980KOhm, the second resistor what is built in row now, has 500KOhm.
With 18°C i get 4,6V and with 120°C 1,8V.
That works really fine!
Just need to switch the OilCooler fan by EMU.

That does not affect the readings of the stock gauge. Or better: you cannot see a difference.

Thank you for your input!

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