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where is a cont. 1volt?

Posted: Mon Jul 12, 2010 8:27 pm
by millsy
does anyone know where a 1volt continuous power can be found? i am converting my AFR gauge to a wideband with another lambda sensor (due to it reading the ecu signals). this will work, i have tested, just trying to find a continuous 1volt thats hooked up2 ignition.
anyone have any ideas? i havnt looked thoughorly yet, does that fto electrical manual have voltage values? thanks

Re: where is a cont. 1volt?

Posted: Mon Jul 12, 2010 9:24 pm
by I8A4RE
I doubt very much you will find one

Re: where is a cont. 1volt?

Posted: Fri Jul 16, 2010 1:18 am
by scanley
the only way is to make your own. you basically work out the resistance of the device, then use a resistor of 11 times that value in series with the device. Use a variable potentiometer to fine tune. There are other ways as well that give you a stable 1v with the input able to vary over small range - say 10v - 14 volt, but it's more complex.

Re: where is a cont. 1volt?

Posted: Fri Jul 16, 2010 6:33 am
by Supplanter
You will need a higher wattage resistor, and it won't be that constant because the voltage from the alternator varies. How good are you with electronics?

Re: where is a cont. 1volt?

Posted: Fri Jul 16, 2010 7:48 am
by scanley
yes, you are right about the wattage, more importantly you need the correct wattage as well as the correct resistance. Essentially wattage is just the physical size of the resistor and it's ability to disipate heat without burning out. If it was me i would be creating a more complex solid state i/c controlled circuit. It is the i/C type circuit that gives a controlled output as you are correct, the final voltage will change with input voltage if you just use a resistor. Electronics - thats my trade, it's what i did in the military.

:)

Re: where is a cont. 1volt?

Posted: Fri Jul 16, 2010 10:09 am
by Dras
The point of a wide band o2 sensor is to give you a more accurate reading than a stock o2 sensor. Give it a rubbish 1V reference voltage and it will give you rubbish readings.

If the 1V it uses is a reference voltage I would use an analog devices ADR130AUJZ-R2 chip. 2-18V in, accurate 1V out. This chip however only provides very little power so it can only be used as a reference. (Type the part number into au.farnell.com)

If you need 1V to power the device, I would go the trusty LM317. Pretty easy to setup, can supply up to 1A (not in this case as there is say a 13V drop and it will not dissipate 13W of heat without cooking) and can be bought from just about everywhere (jaycar, farnell, rs components, digikey)

Setting up a voltage divider with resistors is really a bad idea. If you tune it for say 12V, when the car is running and the alternator is pumping out 14V your voltage will go up over 1.15V. Resistors also change there value over the temperature range. I reiterate, really a bad idea.

Re: where is a cont. 1volt?

Posted: Fri Jul 16, 2010 10:18 am
by I8A4RE
Just buy a UEGO wideband gauge. Everything you need including a bosch wideband o2 sensor.

Re: where is a cont. 1volt?

Posted: Fri Jul 16, 2010 7:53 pm
by scanley
exactly, i was going to research the chip numbers today but never got a chance - thanks for doing it.