Electricty cabling regulations

What are the rules (in NSW, if that matters) with regards to the depth
of electrical cables under concrete? I've been watching some cables
being laid that are directly under about 100mm of concrete.

--
-----BEGIN GEEK CODE BLOCK-----
Version: 3.1
GIT d- s: a--- C+++ UL++++ UB+++ P+ L++ W+ N++
w--- PGP++ t+ 5++ X++ tv b DI+ D++
------END GEEK CODE BLOCK------

 

[John Crighton]

On 24 Feb 2004 08:17:25 GMT, mathew@spamtrap-spiesareus.yi.org wrote:

What are the rules (in NSW, if that matters) with regards to the depth
of electrical cables under concrete? I've been watching some cables
being laid that are directly under about 100mm of concrete.

--
Hello Mathew,

since my kid is doing an electrical apprenticeship, I just yelled
out and asked him "How deep is the minimum depth for cables?"

The rough answer is 0.5 metres minimum depth in dirt.
Minimum depth O.3 metres below concrete provided the
concrete is at least 75 mm thick.

Then my kid started asking "What type of cable?"
"Is it in conduit?"
If you want a more detailed answer you will have to
spend time flicking through the "wiring rules" book.

Cheerio,
John Crighton
Hornsby Heights

 

On 2004-02-24, John Crighton <john_c@tpg.com.au> wrote:

On 24 Feb 2004 08:17:25 GMT, mathew@spamtrap-spiesareus.yi.org wrote:

What are the rules (in NSW, if that matters) with regards to the depth
of electrical cables under concrete? I've been watching some cables
being laid that are directly under about 100mm of concrete.

--
Hello Mathew,
since my kid is doing an electrical apprenticeship, I just yelled
out and asked him "How deep is the minimum depth for cables?"

The rough answer is 0.5 metres minimum depth in dirt.
Minimum depth O.3 metres below concrete provided the
concrete is at least 75 mm thick.

It's 100mm concrete, and the conduit is no more than 30mm below the
concrete.

Then my kid started asking "What type of cable?"
"Is it in conduit?"

I'm not too sure about the cable, but it's in an orange plastic conduit.

If you want a more detailed answer you will have to
spend time flicking through the "wiring rules" book.

I was going to do that, but Standards Australia want $70 just for a
downloadable PDF.

Thanks

--
-----BEGIN GEEK CODE BLOCK-----
Version: 3.1
GIT d- s: a--- C+++ UL++++ UB+++ P+ L++ W+ N++
w--- PGP++ t+ 5++ X++ tv b DI+ D++
------END GEEK CODE BLOCK------

 

[Russ]

<mathew@spamtrap-spiesareus.yi.org> wrote in message
news:slrnc3m5sf.5k0.mathew@alpha.spiesareus.yi.org...

On 2004-02-24, John Crighton <john_c@tpg.com.au> wrote:
On 24 Feb 2004 08:17:25 GMT, mathew@spamtrap-spiesareus.yi.org wrote:

What are the rules (in NSW, if that matters) with regards to the depth
of electrical cables under concrete? I've been watching some cables
being laid that are directly under about 100mm of concrete.

--
Hello Mathew,
since my kid is doing an electrical apprenticeship, I just yelled
out and asked him "How deep is the minimum depth for cables?"

The rough answer is 0.5 metres minimum depth in dirt.
Minimum depth O.3 metres below concrete provided the
concrete is at least 75 mm thick.

It's 100mm concrete, and the conduit is no more than 30mm below the
concrete.

Then my kid started asking "What type of cable?"
"Is it in conduit?"

I'm not too sure about the cable, but it's in an orange plastic conduit.

If you want a more detailed answer you will have to
spend time flicking through the "wiring rules" book.

I was going to do that, but Standards Australia want $70 just for a
downloadable PDF.

What was stated above is what the Wiring Rules say - the cable should be at
least 300mm below a concrete slab that is at least 75mm thick. Where there
isn't concrete (or, by deduction, it is less than 75mm thick) it should be
at least 500mm deep. If the conduit wasn't orange, they'd have needed to lay
orange marker tape up to 200mm above the conduit.

Russ.

 

[David]

On Tue, 24 Feb 2004 11:17:27 +0000, mathew wrote:

On 2004-02-24, John Crighton <john_c@tpg.com.au> wrote:
On 24 Feb 2004 08:17:25 GMT, mathew@spamtrap-spiesareus.yi.org wrote:

What are the rules (in NSW, if that matters) with regards to the depth
of electrical cables under concrete? I've been watching some cables
being laid that are directly under about 100mm of concrete.

--
Hello Mathew,
since my kid is doing an electrical apprenticeship, I just yelled out
and asked him "How deep is the minimum depth for cables?"

The rough answer is 0.5 metres minimum depth in dirt. Minimum depth O.3
metres below concrete provided the concrete is at least 75 mm thick.

It's 100mm concrete, and the conduit is no more than 30mm below the
concrete.

Then my kid started asking "What type of cable?" "Is it in conduit?"

I'm not too sure about the cable, but it's in an orange plastic conduit.

If you want a more detailed answer you will have to spend time flicking
through the "wiring rules" book.

I was going to do that, but Standards Australia want $70 just for a
downloadable PDF.

Thanks

Mathew,

It also depends on the location and the type of cabling.

The wiring rules allow the installation of cables within the confines of a
building, installed below a continuous concrete paved area of mimimum
thickness of 75mm. The 500mm in earth and 300mm below concrete apply to
outside cables.

Also, if the cables are extra low voltage, then there is no depth of
burial requirement.

David

 

On 2004-02-24, David <no_way@hotmail.com> wrote:

On Tue, 24 Feb 2004 11:17:27 +0000, mathew wrote:

On 2004-02-24, John Crighton <john_c@tpg.com.au> wrote:
On 24 Feb 2004 08:17:25 GMT, mathew@spamtrap-spiesareus.yi.org wrote:

What are the rules (in NSW, if that matters) with regards to the depth
of electrical cables under concrete? I've been watching some cables
being laid that are directly under about 100mm of concrete.

--
Hello Mathew,
since my kid is doing an electrical apprenticeship, I just yelled out
and asked him "How deep is the minimum depth for cables?"

The rough answer is 0.5 metres minimum depth in dirt. Minimum depth O.3
metres below concrete provided the concrete is at least 75 mm thick.

It's 100mm concrete, and the conduit is no more than 30mm below the
concrete.

Then my kid started asking "What type of cable?" "Is it in conduit?"

I'm not too sure about the cable, but it's in an orange plastic conduit.

If you want a more detailed answer you will have to spend time flicking
through the "wiring rules" book.

I was going to do that, but Standards Australia want $70 just for a
downloadable PDF.

Thanks

Mathew,

It also depends on the location and the type of cabling.

The wiring rules allow the installation of cables within the confines of a
building, installed below a continuous concrete paved area of mimimum
thickness of 75mm. The 500mm in earth and 300mm below concrete apply to
outside cables.

This is outside, running along a street.

Also, if the cables are extra low voltage, then there is no depth of
burial requirement.

These are 240V mains cables.

Thanks David

--
-----BEGIN GEEK CODE BLOCK-----
Version: 3.1
GIT d- s: a--- C+++ UL++++ UB+++ P+ L++ W+ N++
w--- PGP++ t+ 5++ X++ tv b DI+ D++
------END GEEK CODE BLOCK------

 

[John Crighton]

On 24 Feb 2004 11:17:27 GMT, mathew@spamtrap-spiesareus.yi.org wrote:

If you want a more detailed answer you will have to
spend time flicking through the "wiring rules" book.

I was going to do that, but Standards Australia want $70 just for a
downloadable PDF.

Thanks

Hello again Mathew,
why not try your local TAFE library or local electrician for a
look at the rule book. I had a look in my kid's book and
there are too many if's and but's and clauses to look up.
Inside a building outside a building.

You could even ask the contractors on the job that you
are getting concerned about. The contractors might even
be helpful since you are showing an interest in their work.
The worst they can do is tell you to mind your business.
Nothing ventured nothing gained. It is all in the approach.
Most people are helpful.
Cheerio,
John Crighton
Hornsby

 

[David]

This is outside, running along a street.

Also, if the cables are extra low voltage, then there is no
depth of
burial requirement.

These are 240V mains cables.

The method of installation for supply mains is at the discretion
of the supply authority. So it depends on who is the supplier and
what their installations requirements are. If they were
contractors laying the cable then the work will most likely be
inspected by the supply company. Assuming they have enough
inspectors to get there before the concrete is poured.

If it was laid fairly shallow it may have been amoured cable, but
even so the depth you mentioned sounds unusual as there has to be
allowance for opening (cutting) the concrete and 30 mm certainly
doesn't sound like enough.

Similiar topic, I watched a bunch of Telstra contractors pull a
new 200 m long cable the other day (don't know if it was copper or
fibre). The drum was lying on its side on the ground and the
cable 'uncoiled' over the lip. For those not in the know this
will severely twist and kink the cable, possibly damaging it from
the drawing forces, plus the twists open up when the force is
removed effectively blocking the duct and making it exceedingly
difficult to pull anything else up the duct, or to withdraw the
twisted cable. Cable should always be unrolled with the drum on a
stand.

 

On 2004-02-25, David <maildrop@telstra.abuse.com> wrote:

This is outside, running along a street.

Also, if the cables are extra low voltage, then there is no
depth of
burial requirement.

These are 240V mains cables.


The method of installation for supply mains is at the discretion
of the supply authority. So it depends on who is the supplier and
what their installations requirements are. If they were
contractors laying the cable then the work will most likely be
inspected by the supply company. Assuming they have enough
inspectors to get there before the concrete is poured.

If it was laid fairly shallow it may have been amoured cable, but
even so the depth you mentioned sounds unusual as there has to be
allowance for opening (cutting) the concrete and 30 mm certainly
doesn't sound like enough.

Similiar topic, I watched a bunch of Telstra contractors pull a
new 200 m long cable the other day (don't know if it was copper or
fibre). The drum was lying on its side on the ground and the
cable 'uncoiled' over the lip. For those not in the know this
will severely twist and kink the cable, possibly damaging it from
the drawing forces, plus the twists open up when the force is
removed effectively blocking the duct and making it exceedingly
difficult to pull anything else up the duct, or to withdraw the
twisted cable. Cable should always be unrolled with the drum on a
stand.

I remember an incident like that where the big T fucked up several miles
of fibre doing that.

--
-----BEGIN GEEK CODE BLOCK-----
Version: 3.1
GIT d- s: a--- C+++ UL++++ UB+++ P+ L++ W+ N++
w--- PGP++ t+ 5++ X++ tv b DI+ D++
------END GEEK CODE BLOCK------

 

On 2004-02-24, John Crighton <john_c@tpg.com.au> wrote:

On 24 Feb 2004 11:17:27 GMT, mathew@spamtrap-spiesareus.yi.org wrote:


If you want a more detailed answer you will have to
spend time flicking through the "wiring rules" book.

I was going to do that, but Standards Australia want $70 just for a
downloadable PDF.

Thanks

Hello again Mathew,
why not try your local TAFE library or local electrician for a
look at the rule book. I had a look in my kid's book and
there are too many if's and but's and clauses to look up.
Inside a building outside a building.

I saw a mate today who's an electrician, and he said the same thing. He
said the standards are a basically guidelines - while it's not
compulsory to comply with them, but if you don't, you won't find work
for yourself (as an electrician) - it's like what union membership is in
some industries.

You could even ask the contractors on the job that you
are getting concerned about. The contractors might even
be helpful since you are showing an interest in their work.
The worst they can do is tell you to mind your business.
Nothing ventured nothing gained. It is all in the approach.
Most people are helpful.
Cheerio,
John Crighton
Hornsby

It's the local council. These are street light cables up the main drag,
which is being ripped up and widened etc.

--
-----BEGIN GEEK CODE BLOCK-----
Version: 3.1
GIT d- s: a--- C+++ UL++++ UB+++ P+ L++ W+ N++
w--- PGP++ t+ 5++ X++ tv b DI+ D++
------END GEEK CODE BLOCK------