difference of Grounding and Bonding

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kens
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difference of Grounding and Bonding

Post by kens » Sun Jun 17, 2018 7:16 am

Bonding is something that great many folks can't wrap their head around, and understandingly so.
I'll take a stab at making sense of it.
We all know that any circuit needs a ground in order to work, the deal is that with a simple circuit like a electric motor or light bulb, what we percieve as 'ground' is really a resistance circuit.
Many times an electrical diagram may call out continuity as <3ohms. Different engineers with different wiring prints call out different threshold to comply with the term 'continuity'. For this discussion I will call out <3ohms as continuity.
With this being said, you could take a light bulb or little motor, and place a 2.9ohm resister in the ground circuit and the light still comes on and the motor still runs, even though there is ohms of resistance in the circuit.

When you get into higher accuracy equipment, the engineers begin to call out 'bonding'.
Bonding has more accurate threshold for continuity.
Bonding is continuity down to 0.00002ohm of resistance.

Galvanic corrosion is dissimilar metals making electricity aka a battery.
Galvanic corrosion happens in that area between 3ohm (accepted grounding) and .00002 ohm.
Galvanic corrosion happens in that area that you percieve you got a 'ground', but in reality you a resistance to ground, you can't see it, can't feel it, and you need specialized ohm meter to measure it. An ohm meter to get down to .00002ohm measurement starts at about $5000, thats why few people understand it, and can't see it.

Stray voltage will look like galvanic corrosion, and acts the same way. Stray voltage comes from a bad alternator, bad wire insulation, bad ground or any multitude of improper electrical practices. Most of the time 'bonding' is used as the answer to stray voltage, when in reality, the real answer is to fix the bad ground on the bad device.
In a very complex circuit you may have stray voltage regardless, you can take the leads of a good meter hold them in your hands and get a stray voltage reading.
Bonding is a means to drain off stray voltage to ground, such that galvanic corrosion cannot get started.
Oak is over rated, everything about it takes extra time; then it warps, splits or checks !!! :roll:

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mrintense
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Re: difference of Grounding and Bonding

Post by mrintense » Sun Jun 17, 2018 2:58 pm

Thanks for posting this Ken. Between this and some of the other material I've been reading, I am starting to get a better feel for what has to be done.
Carl
a.k.a. Clipper

Crafting a classically styled Vera Cruise named "Some Other Time"

Clipper's Vera Cruise Build

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kens
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Location: Coastal Georgia

Re: difference of Grounding and Bonding

Post by kens » Sun Jun 17, 2018 4:42 pm

I saw this and thought to post it. It is specifically aimed at marine industry, while I myself am in the aviation industry (avionics) and we deal a lot with grounding/bonding.

https://www.proboat.com/2015/04/the-mys ... -revealed/

Notice this article refers to bonding as <1ohm threshold for continuity.
The trick is to get down to <1ohm.
But, how do you get there???
I'll follow up on that a bit later.
Oak is over rated, everything about it takes extra time; then it warps, splits or checks !!! :roll:

Harryleo
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Re: difference of Grounding and Bonding

Post by Harryleo » Wed Oct 10, 2018 4:41 am

My name is Harry Leo I lived in Birmingham UKBonding is simply the act of joining two electrical conductors together. These may be two wires, a wire, and a pipe, or there may be two Types of equipment. Bonding has to be done by and earthing make sure to protect the short circuit of electric equipment and save the life.

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