Grouding cable

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kukushka
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Grouding cable

Post by kukushka » Fri Feb 02, 2018 6:48 am

Hello,

I made a grounding cable where the other end is a common welding clamp with a 5-meter long 16mm2 wire attached to a fullmetal grouding block reguarly used in cabinets.

I had problems finding good grounds or attaching the small crocodile clips to them, so it this setup OK to use? With this I always hook the clamp to the best source and the crocodile clips to the grounding block. I made it long enough to work in the rear and use the clamp in the battery for example.

If this is OK, can I keep the cable rolled if I don't need the full lenght?

Thanks.

ben.martins
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Re: Grouding cable

Post by ben.martins » Fri Feb 02, 2018 10:53 am

Hello Kukushka,

When you say you have had trouble finding grounds is this because of a noisy signal?

With the majority of our automotive tests we recommend using the battery negative terminal as a common ground point. This is usually more than adequate to give you a good ground point and if required we can use filtering post capture to clean the signal. There is nothing wrong with the setup as you're basically making a extension of the battery earth and providing there isn't too much resistance in the wire you shouldn't have a problem, but there should really be nothing wrong with using any metal part of the vehicle that is connected to the battery negative. If you could explain a bit more about the type of tests you are carrying out and the problems or concerns you are having I'd be happy to assist.

Kind regards

Ben

kukushka
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Re: Grouding cable

Post by kukushka » Fri Feb 02, 2018 6:05 pm

Hello Ben,

Nothing of that sort. I work much with equipment that have the battery hidden, and usually thick steel structures so the clips won't open as much as needed. So it is easier to use the clips where they bite and attach the big clamp to a good ground connection. Usually the chassis is covered in all kinds of soot, so a good grounding place can be meters away.

ben.martins
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Re: Grouding cable

Post by ben.martins » Mon Feb 05, 2018 8:43 am

Hello Kukushka,

Ah, I see. May I ask which kit you are using? Most of the automotive clips come with this type of clip for battery or chassis grounding.

https://www.picoauto.com/products/clips ... ttery-clip

That being said you shouldn't have any issues with the setup you are using. If you know the which wire at the component is the earth wire there is also nothing stopping you from using that either. We do recommend though to always use the battery ground as some wiring diagrams can have the wrong details.

If you need any further assistance please don't hesitate to get in touch.

Kind regards

Ben

kukushka
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Re: Grouding cable

Post by kukushka » Wed Feb 07, 2018 4:39 am

It is a 4425 custom kit as don't need all the automotive accessories, and yes, I have those clips aswell.

Sometimes I feel the connection is better with the large clamp.

As there are no problems to expect, I will continue using it when necessary.

Thanks.

victor2k
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Re: Grouding cable

Post by victor2k » Wed Feb 07, 2018 2:49 pm

kukushka wrote:Hello,

I made a grounding cable where the other end is a common welding clamp with a 5-meter long 16mm2 wire attached to a fullmetal grouding block reguarly used in cabinets.

I had problems finding good grounds or attaching the small crocodile clips to them, so it this setup OK to use? With this I always hook the clamp to the best source and the crocodile clips to the grounding block. I made it long enough to work in the rear and use the clamp in the battery for example.

If this is OK, can I keep the cable rolled if I don't need the full lenght?

Thanks.
A rolled cable is a coil,so you can have some interferences on the gnd point!
The sensors use gnd from engine,the actuators use gnd from battery.
Use a shielded cable for your singal,the ground wire must be short and can be applied at both sides :lol:
An adapter for BNC connector to gnd-something like gnd wire from MI007 cable.

kukushka
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Re: Grouding cable

Post by kukushka » Thu Feb 08, 2018 9:20 am

victor2k wrote:
kukushka wrote:Hello,

I made a grounding cable where the other end is a common welding clamp with a 5-meter long 16mm2 wire attached to a fullmetal grouding block reguarly used in cabinets.

I had problems finding good grounds or attaching the small crocodile clips to them, so it this setup OK to use? With this I always hook the clamp to the best source and the crocodile clips to the grounding block. I made it long enough to work in the rear and use the clamp in the battery for example.

If this is OK, can I keep the cable rolled if I don't need the full lenght?

Thanks.
A rolled cable is a coil,so you can have some interferences on the gnd point!
The sensors use gnd from engine,the actuators use gnd from battery.
Use a shielded cable for your singal,the ground wire must be short and can be applied at both sides :lol:
An adapter for BNC connector to gnd-something like gnd wire from MI007 cable.
This is what I was afraid of. Strangely Pico did not seem to mind. I can make that cable but I don't understand the smiley?

ben.martins
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Joined: Tue May 16, 2017 1:02 pm

Re: Grouding cable

Post by ben.martins » Thu Feb 08, 2018 2:22 pm

Hello kukushka,

I must apologise, I didn't see the part you had mentioned about using this technique with the cable in a coil. Victor2k is right in saying with a rolled cable this is effectively now a coil and any current flow will be amplified which could result in some interference.

Going back to what you said about the chassis being covered in soot, I'm intrigued to ask what it is you are working on? Victor also pointed out that the sensors on the engine are connected to the engine ground. This can be the case but they can also be grounded via the ECU which is something else to bear in mind.

If it is length that is a problem, we do our standard test leads in 5m lengths which might be more suitable for the type of work you are doing.

https://www.picoauto.com/products/test- ... a199-ta202

We are always keen to hear feedback and if you have any suggestions as to what we could do to help you overcome the problems you are facing, it would be much appreciated.

Kind regards

Ben

kukushka
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Posts: 29
Joined: Sat Feb 18, 2017 6:30 am

Re: Grouding cable

Post by kukushka » Fri Feb 09, 2018 11:06 am

ben.martins wrote:Hello kukushka,

I must apologise, I didn't see the part you had mentioned about using this technique with the cable in a coil. Victor2k is right in saying with a rolled cable this is effectively now a coil and any current flow will be amplified which could result in some interference.

Going back to what you said about the chassis being covered in soot, I'm intrigued to ask what it is you are working on? Victor also pointed out that the sensors on the engine are connected to the engine ground. This can be the case but they can also be grounded via the ECU which is something else to bear in mind.

If it is length that is a problem, we do our standard test leads in 5m lengths which might be more suitable for the type of work you are doing.

https://www.picoauto.com/products/test- ... a199-ta202

We are always keen to hear feedback and if you have any suggestions as to what we could do to help you overcome the problems you are facing, it would be much appreciated.

Kind regards

Ben
I work with construction machines. Sometimes they work in crushing sites etc. so they are very dirty.

I will extend the cable to it's full lenght if that is ok. There are no problems using Pico's 5m cables other than I need bigger clamps as sometimes the only clean parts in the chassis are too large to clip.

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