# Basic question

J

#### Jimbo

Jan 1, 1970
0
Is there a definition as to what constitutes an "isolated" vs.
"non-isoldated" circuit? What does this really mean? This is what I
think the definition really is:

A system S1 has an input V1,In referenced to V2,In and an output V1,out
referenced to V2,out whereas V1,In - V2,In has an operating limit of L1
and V1,out - V2,out has an operating limit of L2.

Is an isolated system a system that can have the references V2,In and
V2,out such that |V2,In - V2,out| >> 0 and still operate properly? If
so what value of |V2,In - V2,out| constitutes an "isolated system"?

Does anyone know of a formal definition of an "isolated" system? I
know that usually it's some kind of LED operating on some kind of
photo-sensitive device, but is that what the definition is limited to?
I don't think so because a "relay" is usually called an isolated
circuit.

J

#### Jimbo

Jan 1, 1970
0
opps, sorry for the double post...I tried to correct a spelling error.

P

#### Phil Allison

Jan 1, 1970
0
"Jimbo"
Is there a definition as to what constitutes an "isolated" vs.
"non-isoldated" circuit? What does this really mean?

** "Isolated" usually refers to "galvanic isolation" where no
*electrically conductive* path exists between the devices or circuits
concerned.

There is "transformer isolation", "optical isolation", "relay isolation"
.... etc

Using a coupling capacitor between two circuits produces " DC isolation ".

Like most tech terms, the meaning cannot be defined OUT OF CONTEXT !!

FORGET trying to do that !!!!

This is what I
think the definition really is:

** Yawn.....

Does anyone know of a formal definition of an "isolated" system? I
know that usually it's some kind of LED operating on some kind of
photo-sensitive device, but is that what the definition is limited to?
I don't think so because a "relay" is usually called an isolated
circuit.

** A relay provides "galvanic isolation" between the driving and switched
circuits.

........ Phil

J

#### John Popelish

Jan 1, 1970
0
Jimbo said:
Is there a definition as to what constitutes an "isolated" vs.
"non-isoldated" circuit? What does this really mean? This is what I
think the definition really is:

A system S1 has an input V1,In referenced to V2,In and an output V1,out
referenced to V2,out whereas V1,In - V2,In has an operating limit of L1
and V1,out - V2,out has an operating limit of L2.

Is an isolated system a system that can have the references V2,In and
V2,out such that |V2,In - V2,out| >> 0 and still operate properly? If
so what value of |V2,In - V2,out| constitutes an "isolated system"?

Does anyone know of a formal definition of an "isolated" system? I
know that usually it's some kind of LED operating on some kind of
photo-sensitive device, but is that what the definition is limited to?
I don't think so because a "relay" is usually called an isolated
circuit.

An isolated circuit is one that has a very high resistance to what it
is isolated from. The contacts in a relay are isolated from the coil
wire by the wire insulation, the bobbin the wire is wound on, and the
insulation holding the contacts away from other things. All isolation
has some voltage limit, above which current will take a short cut
around the insulation and surface track or arc.

J

#### Jimbo

Jan 1, 1970
0
The reason I'm asking is because I have a circuit with two "floating"
inputs but there is a point where the material breaks down. So,
according to your definition this is not "isolated".

P

#### Phil Allison

Jan 1, 1970
0

The reason I'm asking is because I have a circuit with two "floating"
inputs ......

** Learn to post facts and describe things adequately.

but there is a point where the material breaks down.

** There ALWAYS is.

That's why all real devices have RATINGS - you bloody FOOL

So, according to your definition this is not "isolated".

** You are seriously mentally defective.

GO AWAY !!

........ Phil

J

#### Jimbo

Jan 1, 1970
0
Thanks for you help Phil.

G

#### Grumps

Jan 1, 1970
0
The reason I'm asking is because I have a circuit with two "floating"
inputs but there is a point where the material breaks down. So,
according to your definition this is not "isolated".

So what do you need to know? Do you want a definition of isolation, or an
explanation of why your circuit falls over?

A

#### [email protected]

Jan 1, 1970
0
Phil, you need some hard man-love to relieve your tension. Come to
Montreal, I'll show you where to go. You might want to come here in the
first week of August. We accept autistic Touretters like you. Bring
condoms.

L

#### Luhan

Jan 1, 1970
0
Jimbo said:
The reason I'm asking is because I have a circuit with two "floating"
inputs but there is a point where the material breaks down. So,
according to your definition this is not "isolated".

Shocking!!!!

Luhan

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