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canuckster19 t1_j9sjc8w wrote

Positive, Ground, Negative

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DeexEnigma t1_j9smr5v wrote

Technically 'earth' not 'ground'. But yea, I pretty much saw the same.

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mothballd t1_j9udn5l wrote

I’m an aircraft electrician. There is no “earth” wire on an aircraft, only grounds. The earth vs ground argument is context driven, and also varies by region. Even the wires(braided cables) that hang off the aircraft landing gear to contact the ground when on the ground are called grounding straps/wires, not earth straps or similar.

In the home electrical stuff I’ve done I’ve mostly heard ground. The earth ground is a specific wire run from the main circuit breaker panel that’s then attached to a grounding rod.

I’m u.s. based, so I suspect the earth terminology is used either in specific industries I’m not familiar with, or different regions.

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DeexEnigma t1_j9vdemv wrote

> In the home electrical stuff I’ve done I’ve mostly heard ground. The earth ground is a specific wire run from the main circuit breaker panel that’s then attached to a grounding rod.

That's the angle I'm coming from. In Australia if it's green and it's in an AC application it's going to earth. It's a standard I believe in the EU as well as a couple of other areas.

Ground in AC can exist but will be floated within the device as a neutral return. It's more the wiring colour standard I was picking.

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its_the_other_guy t1_j9vgfts wrote

So, airplanes don't have wireless ground?

*Don't worry, I'm walking myself out.

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Alias-_-Me t1_j9taf7m wrote

What's the difference?

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AnyAmphibianWillDo t1_j9tjoug wrote

I have almost no electrical knowledge but I think "earth" or "earth ground" would imply that wire is connected literally to the earth at some point, e.g. in home wiring there can be a copper rod driven deep into the earth that all the "ground" wires are connected to, making those earth grounds?

I think the word "ground" by itself is often just used to refer to the common (shared) part of a circuit, eg. on an arduino there's a ground (GND) pin that's obviously not connected to the earth, but used as a shared source of "lower electric potential" for all parts of the circuit to use to create the difference in potential required to have "voltage"

Why OP says there is an earth wire in the picture and not just a ground, idk. Those 3 wires could easily be used for something that has no earth ground. Maybe the color scheme of those 3 wires is a standard one and the green usually is earth ground? No idea. Maybe there's just different terminology standards than I'm aware of and in the shitty hobbyist world I live in we all use the words wrong ¯\_(ツ)_/¯

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Odissus t1_j9tnn4x wrote

That’s actually quite accurate! To answer your concerns, for (single phase) AC like in many outlets, ground (the reference voltage) is most convenient to be the same as earth (0V). For this reason calling earth “ground” is fine, as more often than not it’s both earth and ground.

Just to add, any voltage you use often in a circuit as a reference (say for comparators for example) is called a reference ground. So if you split 0 to 5 V in half, and keep using 2.5 V for various comparison purposes, the 2.5 V could be called a reference ground.

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DeexEnigma t1_j9vdw06 wrote

Depending on context. In an AC mains power application the earth wire directly ties to a stake that's in the earth outside. This provides a safe return path for faulty circuit conditions.

Ground is a broad term in DC applications where it is the main negative' plane or hookup. However you can have ground in an AC application where it usually is the neutral return.

Generally green in mains power (Australia/NZ and I believe EU) is always the earth.

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carmium t1_j9ukbqg wrote

Are you well earthed in electrical terminology?

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-St4lker- t1_j9um9o1 wrote

Here in Slovakia (and other Slavic countries) the term for ground and earth is exactly the same. We knew what we were doing :D

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DeexEnigma t1_j9vct63 wrote

I know in Australia the term is often used interchangeably, even if it's wrong. Interesting that there's other areas of the world that the language dictates it being identical.

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