Zdb before dead tests.

[westward10]

Outside my scope of expertise then

 

[Wilko]

Errr, when bein skooled for a Cooking & Gardening qual, this was the term used for that 2nd (or 22nd) board from the origin.

 

[Pete999]

Outside my scope of expertise then

Your words

 

[Risteard]

As westward points out it is the Zs of the distribution circuit. There is no BS7671-defined term "Zdb" so I would agree that it shouldn't be used.

 

[Octopus]

I think common sense is called for here. ............. its distinctly lacking in BS 7671

If you refer to a Zs - its the end of a circuit
If you refer to a Zbd - its obvious its at a sub board

So maybe it should be called a ZeZdb

 

[Deleted member 26818]

As westward points out it is the Zs of the distribution circuit. There is no BS7671-defined term "Zdb" so I would agree that it shouldn't be used.

How does that work say for a garden shed that you intend to TT?

 

[Pete999]

I think common sense is called for here. ............. its distinctly lacking in BS 7671

If you refer to a Zs - its the end of a circuit
If you refer to a Zbd - its obvious its at a sub board

So maybe it should be called a ZeZdb

Or Impedance at the DB Or more sensibly Zdb, what on earth is the argument for, after all it may not be a regulation but Z db makes sense to me

 

[westward10]

Zskt = Zs at socket outlet.
Zltg = Zs at light fitting.

 

[westward10]

I think common sense is called for here. ............. its distinctly lacking in BS 7671

If you refer to a Zs - its the end of a circuit
If you refer to a Zbd - its obvious its at a sub board

So maybe it should be called a ZeZdb

No Zs.

 

[Octopus]

Zdb = Zs at door bell!

 

[westward10]

How does that work say for a garden shed that you intend to TT?

Any ideas too many Zds now.

 

[ipf]

deleted

 

[7029 dave]

I agree but not a abbreviation I ever quote. I believe it has been adopted where a true value of Ze cannot be established due to operational restrictions and the value is often referred to as Zdb which although often quoted is not a recognised abbreviation.

Yes, with main earth conductor in situ , plus all parallel paths connected.

 

[7029 dave]

I agree but not a abbreviation I ever quote. I believe it has been adopted where a true value of Ze cannot be established due to operational restrictions and the value is often referred to as Zdb which although often quoted is not a recognised abbreviation.

Yes, with main earth conductor in situ , plus all parallel paths connected.

 

[Midwest]

Coronation Street not on tonight

 

[KEV 1 N]

Only Z’s I’m thinking of! (Yawn)

 

[Wilko]

Zztop -

 

[Risteard]

How does that work say for a garden shed that you intend to TT?

You will have a Zs for that distribution circuit, and the Zs for the final circuits fed from it will have no correlation with that (ignoring the fact that the phase (or line as it is called now) is common).

 

[Deleted member 26818]

You will have a Zs for that distribution circuit, and the Zs for the final circuits fed from it will have no correlation with that (ignoring the fact that the phase (or line as it is called now) is common).

What will be the Ze/Zs at the board?

 

[Risteard]

What will be the Ze/Zs at the board?

The Zs at the DB will obviously be via the spike. I really get the feeling you're overcomplicating this. I see no merit in a made-up term "Zdb" - Zs covers everything perfectly.