Author Topic: Sensor shields connection  (Read 8035 times)

Offline jadzwin

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Sensor shields connection
« on: September 18, 2007, 12:32:54 pm »
Hello,

It is my first post so I introduce myslef :)
I'm from Poland and actualy I upgrade my DU Espero (C20LE, TB2531, 240hp) to stage II (C20LE + 16V Head, GT28RS, Water Injection, VEMS, want to achieve 330-340hp ). I've just bought vems and I start to make car wiring.
I have one question that I can't answer by myslef and I can't find any noto in Vems Wiki.
Wehere should be shield of Knock Sensor and VR canks sensor (60-20 toothed wheel) connected ?
I want to use ground paths the same as in orginal ECU (there is shitty delco ecu with no knock detecion, and distributor),
but I want to increase the diameter of some ground wires (the common ECU ground is only 1.5mm).

Knock and vr sensor have two wires + shield. On of wire is singnal wire, second is connected to ECU sensro groun.
Weher should be connected shield ? To common ground, sensor ground, somewhere else ?
For example in C20XE Opel Engine (Motronic) there are separet ECU pins for shileds.

Thank you very much for help. I'm pretty sure that this is no last my post here :)

Jadzwin



Offline rob@vems.co.uk

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Re: Sensor shields connection
« Reply #1 on: September 18, 2007, 01:44:31 pm »
Welcome to the forum.

The sheild wire should be connected at one end only, I tend to connect the VR shield wire to the block down near the sensor.
The seperate wire that is connected to the ECU sensor ground pin should not be connected to the shield as that would inject noise into that part of the circuit.

Offline jadzwin

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Re: Sensor shields connection
« Reply #2 on: September 18, 2007, 09:00:44 pm »

So for knock sensor I'm able to wire shield directly to the block.
The problem is with VR sensor because I use orginal sensor cable, where the shield is accesible only on ECU side. Should I connect additional wire between engine block and the shield ?
Or maybe the shield is grounded to the block by sensor itself (it is Opel standard sensor) ?

Thanks
Jadzwin

Offline rob@vems.co.uk

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Re: Sensor shields connection
« Reply #3 on: September 19, 2007, 10:15:46 am »
Ideally you should ground to the block, in reality we cannot always do what is ideal.  You can tie your two shields together and run a wire from them to the VEMS common grounding point.

Offline jadzwin

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Re: Sensor shields connection
« Reply #4 on: September 23, 2007, 04:12:22 pm »
Hello,

Thanks, that is alread clear for me.

I have new question regarding grounding Pin 22. The pin is unconnected on the PCB. Should I wire it to specyfic point on board ? Pin 23 is connected by flyback wire.
I'm very confused about pin 22, and I don't want to destroy my PCB :)

Thanks for help
Jadzwin
« Last Edit: September 23, 2007, 06:40:35 pm by jadzwin »

Offline rob@vems.co.uk

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Re: Sensor shields connection
« Reply #5 on: September 23, 2007, 04:24:06 pm »
What sort of load are you switching with this system?  How many coils/ inejctors and solenoids?

Rob

Offline jadzwin

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Re: Sensor shields connection
« Reply #6 on: September 23, 2007, 05:36:40 pm »

4 high Z injectors, two coils (maybe 4 in future with COPs), 3 relays and 1 wideband heater.


Jadzwin

Offline rob@vems.co.uk

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Re: Sensor shields connection
« Reply #7 on: September 24, 2007, 09:12:17 am »
I pulled apart a unit last night to see how the grounds come from the factory - the two pins are joined by a wire across to the ground line over by the IGBTs on the underside of the board.  It would be as well to do this as earths are never a bad idea :D

Offline jadzwin

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Re: Sensor shields connection
« Reply #8 on: September 24, 2007, 01:25:24 pm »
Thank you very much !!!

I will wire it as you suggest.

So this week I want to run the system on the desk with injectors, coils, 60-2 signal simulator and scope.
I hope I'm able to do it :)

Jadzwin