GM Coolant sensor

[Chris Morriss]

In message <9608198431.AA843148124 at afcperth.aesprodata.com.au>,
dzorde at aesprodata.com.au writes
>
>     That is what they are for, but wouldn,t it be great to get rid of an 
>     op-amp.  Hence try and reduce the amount of circuitry required.  
>     Something like a simple LCD temp read out (very useful for diff, 
>     gearbox and water in race cars), temp sensor, a small resistor divider 
>     and a panel meter, and its guarranteed to be very reliable, once you 
>     start throwing in op-amps, etc.  you need very steady power supply 
>     rails to avoid inaccurate readings.  So is there a positive temp 
>     coefficient sensor around ? (could always make one if I have to, but 
>     its easier if there's a car that's already using one).
>     
>     
>     Dan        dzorde at aesprodata.com.au 
>
>
>______________________________ Reply Separator _________________________________
>Subject: Re: GM Coolant sensor
>Author:  diy_efi at coulomb.eng.ohio-state.edu at INTERNET
>Date:    9/18/96 11:19 PM
>
>
>>     Does anyone know if there's a positive curve temp sensor around, ie. 
>>     increasing voltage for increasing temp.  Would make life a lot easier 
>>     for analogue circuitry.
>>     
>>     Dan        dzorde at aesprodata.com.au
>     
>I thought that's what inverting amps were for. 
>Tom
>     
I use a Nat Semi LM50. This is a linear sensor with an output that
increases with increasing temperature.  The TO92 version can be fitted
into an old dismantled water temp sensor if required.  Use heatshrink
sleeving as insulation.  As it is a 3-wire sensor it needs a +ve feed as
well as the ground and output wire.
-- 
Chris Morriss