TPS specification

General Megajolt Questions and Answers

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Noggy
Posts: 14
Joined: Fri Jul 23, 2010 10:16 am
Location: Basingstoke

TPS specification

Post by Noggy »

Hi everyone.
I've been in and out of here for a few years, having previously built and used a Megasquirt, but have not registered before.
I have just ordered a MJLJ for my oval race car project, a 2 litre Zetec engined Toyota Starlet with Weber DCOEs fitted.
I have tried searching, but have been unable to find the info I need.........

I have access to fairly robust 4 wire TPSs, as used on fork lift trucks. Diagram below;

Image

Because of safety legislation these pots have dual tracks, but thats not an issue, I'll just use 1 track!

My question concerns what MJLJ requires electrically for a tps.

With the pot not connected if I measure between ground (pin 1) and Vref (pin 4) the resistance is 2k ohm.
If I measure between ground and O/P (pin 3) the restance range is between 1k75 and 3k75 ohm.

Before I start making a bracket to fit these type of pot to my Webers would someone be able to confim they will be ok?

Many thanks.

BRUCEROE
Posts: 96
Joined: Wed Mar 03, 2010 10:00 pm

Post by BRUCEROE »

The usual way to use a TPS, is apply +5V and ground to your pins 1 & 4. Then sense voltage out to the MJ from 2 or 3. Th MJ can supply the +5V. Exact resistance not important. Bruce Roe

Noggy
Posts: 14
Joined: Fri Jul 23, 2010 10:16 am
Location: Basingstoke

Post by Noggy »

BRUCEROE wrote:.....Exact resistance not important......
Good news, thank you.

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