Grounding Passing Lamps

[LilBeaver]

I like to keep things neat, especially wiring; my question for others is:

 

Where do you have your passing lamp circuit grounded? All the way back to the fuse block? battery? headlight surrounds?

 

Thanks for the input (just curious here).

[jlh3rd]

there is a tube frame in the fairing that holds the electronic control box.......i used one of the four bolts at the corner as a ground for my lamps from the relay.....

[LilBeaver]

Bump...

[Rick Butler]

Rick,

 

If you are speaking of the ground for the 2 passing lights, there is a black wire on each of the chrome housings that is connected to a rivit that gets its ground from the frame. Now the turn signals and orange running lamps get their ground from one of the two black wires in the bundle of wires that comes with the lights that connect into the bikes current wiring.

 

Now if you wire them up controlled with a relay, you will have to have a ground wire for the relay, but any frame bolt will work just fine. In fact with any accessory wireing, just go to any frame bolt that is close for your ground. This is just DC circuits, not rocket science.

 

Hope this helps,

 

Rick

Edited September 10, 2009 by Rick Butler

[LilBeaver]

Rick:

 

Thanks. I was pretty sure that was the case. I suppose I should have been a little more specific, but I was curious about both the grounds for each lamp as well as the relay that provides power to the lamps.

 

I was not real happy with the way I had things put together under my fairing and was curious if others had a better way to run that wire.

But also:

With my latest electrical woes with my bike I had recalled an experiment I worked on a few years ago where someone in my group, when wiring up an RF amplifier for a resonance experiment, had grounded the unit in one place and effectively another part of the circuit in a second place. These multiple paths to ground caused all sorts of crazy behavior. It was a bit more complex than the bike and I didn't think that grounding stuff to the frame in different places was going to yield the same issue but I just needed some confirmation on that. I don't know why, but often times I really manage to over-think the simple things like this .

It has been a heck of a few weeks here and the few problems I have had with my bike certainly have not been helping...

Anyways, I'm done yammering about my problems.

 

Thanks again.

[Guest tx2sturgis]

With my latest electrical woes with my bike I had recalled an experiment I worked on a few years ago where someone in my group, when wiring up an RF amplifier for a resonance experiment, had grounded the unit in one place and effectively another part of the circuit in a second place. These multiple paths to ground caused all sorts of crazy behavior. It was a bit more complex than the bike and I didn't think that grounding stuff to the frame in different places was going to yield the same issue but I just needed some confirmation on that. I don't know why, but often times I really manage to over-think the simple things like this

 

 

 

DC grounds and RF grounds are not the same thing. RF grounds are affected by frequency and wavelength, and normally, a DC ground is not. With the more or less pure DC ground that the lights require, any decent ground on the frame, the battery, the wiring harness, or the electronics modules will work, as long as the current capacity is observed.

[KiteSquid]

Where do you have your passing lamp circuit grounded?

 

I ran mine to the point the black battery cable connects to the bike.

 

It is important to keep from introducing ground loops in vehicles.

[jlh3rd]

what do you mean, introducing ground loops

[Dave77459]

I ran a wiring pair from the auxiliary fuse box I installed under the seat, to the relay. The relay is therefore grounded at the battery, and the lamps are grounded wherever the dealer did it.

 

Dave

[LilBeaver]

...

It is important to keep from introducing ground loops in vehicles.

 

This is what I was worried about...

 

what do you mean, introducing ground loops

 

A ground loop occurs when there are multiple paths to ground before a true ground and one of the points has a different potential than another. For example, one point would have 0.0V and another point may have 0.2V. This potential difference (difference in voltage) will give rise to a current.

[Steve S]

I ran a new ground wire, 10ga, from my battery to one of the mounting bolts for the electrical box under the fairing. That is what I use for all of my ground connections.

[jlh3rd]

so.....is that what i did by using that small tube frame that supports the amplifier as a ground.........and what problems does this cause

[SilvrT]

A ground loop occurs when there are multiple paths to ground before a true ground and one of the points has a different potential than another. For example, one point would have 0.0V and another point may have 0.2V. This potential difference (difference in voltage) will give rise to a current.

 

 

wwaaaaaaaaaaaaaaaaaaaaayyyyyyyyyyyyyyyyyyyy over my head!

 

I also used the tube frame inside the fairing for a grounding point for my little "running" lights as well as my gauges and I'll use that same ground for anything else I hookup on the front.

[jlh3rd]

well, i think i understand what he's saying....i have possibly caused a current to now flow from the grounding point in my fairing to , i guess, the ground for the battery....i need to know what problems that can cause.......and i guess the fix is to run a ground wire from the battery to the little frame

[SilvrT]

well, i think i understand what he's saying....i have possibly caused a current to now flow from the grounding point in my fairing to , i guess, the ground for the battery....i need to know what problems that can cause.......and i guess the fix is to run a ground wire from the battery to the little frame

 

Why not just run a good sized (say 16 or 14 gauge) wire from the battery negative post to a "block" inside the fairing that has a threaded post on it. Then, all things you add that need grounding can be connected to that.

[jlh3rd]

exactly

[LilBeaver]

I am not sure as this is a problem on the bike.

 

If there is negligible resistance on the frame then anywhere along the conducting surface of the frame ought to have the same potential which would cause this to be a non-issue.

 

Running a wire from the negative terminal on the battery, or from the main ground point on the bike up front to the lug that you have stuff grounded to under the fairing would work to alleviate this 'problem' (if it truly is a problem).

 

My objection to the validity of this being an issue at all is that the bike is 'grounded' by the frame and that is all. So being that the bike has a (nominally) 12V electrical system, one could actually have a bike that functioned perfectly fine if the frame had managed to have an electrical charge relative to a 'true' ground (ie. earthed ground) as long as there was a 12V difference between anything that is supposed to have 12V across it. For example if the frame had a potential (with respect to earth ground) of 5V, so long as the 'negative' terminal on the battery also had a +5V difference and positive terminal had a +17V difference with respect to earth ground. Note that there is still a 12V terminal voltage across the battery and this would only work if the rest of the charging system was designed to deal with this - I used this as an example to simply display the principle so lets leave it at that.

That being said, the frame is taken to be ground, or 0V, since that is where the 'negative' battery terminal is connected to, etc. So, going back to my original statement that would assume negligable resistance throughout the frame, and assuming the frame is a reasonable conductor (which it obviously IS); conductors, by properties of basic electromagnetism, are equipotential surfaces with all charge being stored on the surface thereby suggesting that if you 'ground' an electrical component ANYWHERE on the frame it should suffice as an appropriate ground with no other complications.

 

I know for sure ground loop issues can appear in an electric circuit that is connected to an earthed ground. In a case of audio/visual equipment where electronics are connected to a power supply (that have a ground plug on them which ground the power supply, and anything else on that circuit to earth ground and any other ground plug on that circuit) and are also connected with another cable (coaxial, or whatever) where if the coaxial cable connects you to an anntena, the antenna may be grounded too. In this kindof setup ground loops will show up as 'noise' in the visual signal (or sometimes auditory depending on what it is that is going on) but this also is a different animal because this involves AC circuitry as well.

 

I don't know that this helps at all, but hopefully it provides a little more insight, at least from a theoretical prospective... Hopefully someone with practical experience with this can chime back in and set us straight.

[jlh3rd]

got it !........i'm OK....

now ,just explain how we can have multiple dimensions in time and space at the same time, yet be invisible due to the string theory and quantum mechanics......and i'll be happy

[SilvrT]

got it !........i'm OK....

now ,just explain how we can have multiple dimensions in time and space at the same time, yet be invisible due to the string theory and quantum mechanics......and i'll be happy

 

 

Smoke a big FATTY !! :rotf:

[LilBeaver]

...

now ,just explain how we can have multiple dimensions in time and space at the same time, yet be invisible due to the string theory and quantum mechanics......and i'll be happy

 

Haha, well... Quantum Mechanics actually is not all that difficult... String theory is another story. The fact that the theory is structured in such a way to suggest that it is impossible to actually test (based on the theory itself) allows it to get poo pooed by most REAL scientists...

But, I get the humor in your statement but maintain that I'd be happy to talk Physics with you if you'd like. :-D

[LilBeaver]

Hopefully KiteSquid will weigh in on this again to give us some more insight...

[LilBeaver]

While installing my new radio today I get everything hooked up and decide to do a little investigation.

 

I have had my passing lamp relay grounded on the bolt at the headlight surrounds - that is the switching portion of the relay. Current through that wire with lamps on is only 0.1A. Voltage between the ground point of the radio and that point on the headlamp surrounds is 30 mV with the radio off and ~24 mV with the radio on.

 

I am quite confident that this should not have an adverse affect on the radio or the other electrical components on the bike.

Other opinions are certainly welcome though; let me know if you disagree

[KiteSquid]

there are people here that have had problems with ground loops in their electrical systems.

 

So why risk adding a ground loop???????

 

 

Ground where the battery gounds and 99.999999999999999999999999% of the time you will NOT intorduce a ground loop.

[LilBeaver]

there are people here that have had problems with ground loops in their electrical systems...

 

Well that is good to know and what I was curious about to begin with...

I'll fork over the $1.00 for a few feet of wire to git-er-done and not worry about it. That 1.00 sure beats having to buy ANOTHER radio...