2 x 6 sq mm braided wire vs 2 x 2.5 sq mm solid copper for main power

[likethemthin]

Hello:

I read the FAQ about electric cables, but I thought "braided" wire was less desirable than solid copper. I am installing a Safety-Cut between main lines coming in and my 63A service panel (single phase service).

I need a short wire from the Safety-Cut breaker back to the electric panel. I am wondering what wire I can use. The Thai electrician seems to want to use 2 x 6 sq mm braided wire from Home Pro. By "braided" I mean there is more than one wire in the cable and the pieces are less than 2.5 sq mm each. I also have available 2 x 2.5 sq mm which is solid copper wire (not braided); and also I have some left over rather thick braided copper wire with green insulation used to ground my entire system (runs from panel box to long large copper stakes poked into the soil outside the house).

So my question is are any of these wires suitable to carry my main electric current from the Safety-Cut back to my electric panel, about 30 cm?

I am starting to think possibly none of these three are appropriate and will either burn up or create resistance so that I will be losing some power.

I am not sure what to do, as it is difficult to buy a small piece of "mains" wire, but I did find an expensive roll of I think 2 x 16 that electric salesman said was used for main house power.

Any advice or input would be very appreciated. Seems I may be creating a big problem where none existed. I wonder what people use for wire when installing a Safety-Cut circuit breaker??

Walter

[Crossy]

Before you start a fire:-

2.5mm² is rated at about 30A (varies with type but all are about that or slightly less), at 60A it's going to start smoking.

6mm² is rated at about 50A, at 60A it's going to be very warm.

For a 63A incomer you're looking at 10mm² as an absolute minimum, 16mm² would be the correct choice.

Absolutely nothing wrong with stranded cable of the same cross-sectional area, it's easier to manage.

Whilst not ideal (it's green) what size is the green stuff, it should be printed on the insulation?

[likethemthin]

Thank you so much, that is what I was afraid of. When you say 16 mm2, is that copper? If aluminum, which is likely all I will be able to find a Home Pro or Thai Watsudu in another province I have to drive to, I saw a roll marked 16 and one marked 25 but was clearly aluminum (or steel I really don't have any idea, but NOT copper). So, if aluminum, is 16 mm2 still good or should I be looking at 25 mm2? I am only running about 30 cm from Safety Cut to main panel.

On my street, when I had to bring the electric down the country road, I am pretty sure PEA was 50mm2 aluminum. Then I ran I believe 35 mm2 copper from street 150 meters to my house.

Wow, I am very boring, but anyway thanks again and I will bird dog much larger wire.

I will check on my green wire tomorrow, I did not spot any writing, but may need to look at more length, but is does seem heavier than 6 mm2.

Walter

[Crossy]

Don't use anything other than copper inside your home. Yes that's 16mm² copper to link your Safe-T-Cut to the panel.

I don't think I've seen Al cable in HomePro.

[Paul944]

Always use the right color cable. Using the yellow/green thick wire for a live is a very bad idea and can give someone working on the installation a deadly surprise.

How thick is the main cable? No use to use a thicker cable as that one.

How much amps is the circuit breaker? this 2x6 mm^2 should be fine and even the 2x2.5 mm^2 will do it for a 30 Ampere circuit breaker.

[Crossy]

Always use the right color cable. Using the yellow/green thick wire for a live is a very bad idea and can give someone working on the installation a deadly surprise.

How thick is the main cable? No use to use a thicker cable as that one.

How much amps is the circuit breaker? this 2x6 mm^2 should be fine and even the 2x2.5 mm^2 will do it for a 30 Ampere circuit breaker.

Very poor advice.

OP states that his panel is 63A, he also states his incoming supply is 16mm².

Neither 2.5mm² nor 6mm² is suitable, period!!!

His "thick" cable is green (not yellow/green), whilst I agree 100% it's unwise to use for live conductors it's not a hazard per-sé and it's only a 30cm run.

To our OP, HomePro sell cable by the metre, so it should be no real difficulty getting the correct stuff. Your installer should have it anyway.

[likethemthin]

My "green" ground wire just has no markings, and I have 10-15 meters, cannot find any markings. I cut it clean and it measures 3 mm cross section (not insulation, wire portion only), containing 6 strands in a circle with one in the middle, and for sure is a lot thicker than the 2 x 6 mm2. While it would probably work, I will follow the suggestions to purchase correct known wire size and be safe. I do have the regular cable feeding into the Safety Cut as it will just be removed from the panel box entry and relocated to Safety Cut, so input is OK, just need that darn 30 cm output back to panel.

Many thanks to all.

[Crossy]

You probably have THW cable, this table shows the various cable sizes http://www.bangkokcable.com/product/backoffice/file_upload/131004_1-450!750V%2070C%2060227%20IEC%2001%20(THW).pdf note the conductor sizes.

I suspect that your green cable is actually 10mm², in which case it would be OK as a TEMPORARY installation, tape the ends black and white (L and N) to indicate its real function.

How are you measuring its diameter? Best to measure 1 strand with a vernier, work out its CSA by pi.r², then multiply by the number of strands.

[likethemthin]

Well, I understand your formula, but not sure I have that accurate measuring equipment. On the chart, closest seems to be a diameter of 3.09 mm with 7 wires total handling 48 amps. Certainly better than what my thai "electrician" was going to use: 2 x 6 mm2!! But as the operative word is "temporary", I will proceed to get the wire you recommended.

Thank you so much, as I do not know very much, just trying to peer over shoulder of "installer" so my whole system doesn't blow up. Hmmm, seems he mentioned someone's system blowing up...I wonder was he involved in that job??

I will also go look at the meter end to see whether I can get lucky and have a bit extra main copper cable at that end that I can use.

[gandalf12]

You never use braided wire for mains cables always solid core. Do not use braided it is a very bad choice. The reason is one or more of the strands can break. This will increase the heat dissipation in the cable and can lead to a fire.

[gandalf12]

Before you start a fire:-

2.5mm² is rated at about 30A (varies with type but all are about that or slightly less), at 60A it's going to start smoking.

6mm² is rated at about 50A, at 60A it's going to be very warm.

For a 63A incomer you're looking at 10mm² as an absolute minimum, 16mm² would be the correct choice.

Absolutely nothing wrong with stranded cable of the same cross-sectional area, it's easier to manage.

Whilst not ideal (it's green) what size is the green stuff, it should be printed on the insulation?

Sorry to disagree with you but you do not use braided wire for this application. It is a no no

[bankruatsteve]

You never use braided wire for mains cables always solid core. Do not use braided it is a very bad choice. The reason is one or more of the strands can break. This will increase the heat dissipation in the cable and can lead to a fire.

Mains cable is almost ALWAYS braided. Where are you from?

[Crossy]

Gandalf12, please can you quote a credible reference for this, English preferred but any language would be OK. It certainly isn't common practice in the UK.

Note, we are not talking about multi strand flexible cable with many fine strands (which should not be used for fixed wiring), we are talking about cable intended for fixed wiring consisting of a few thick strands.

The sort of stuff found here http://bangkokcable.com/product/backoffice/file_upload/131004_1-450!750V%2070C%2060227%20IEC%2001%20%28THW%29.pdf

You may note that anything bigger than 10mm² is not available as solid core, even as 7 strand 25mm² is a wrestle to get into a standard distribution board.

You may also wish to consider what happens if you lose one strand of a single strand cable

EDIT By the way "braided" is the wrong word that would describe a braid such as that used for grounding moving panels (doors).

This sort of stuff, definitely not suitable for the purpose:-

[likethemthin]

I went to the Thai Watsudu in Nong Bua Lamphu to get wire, but they would not break 100 meter rolls for me, Home Pro too in Loei would not break, but I found just past Thai Watsudu a Tesco Lotus, and next to it was a Best Lighting Supply which had every wire and you could buy any length. This is fairly close to line with Udonthani if anyone in that area.

As my meter is 30/100, and my incoming copper line to Main panel is 35, I bought a short section of size 25 to connect output from Safety Cut to Main Panel. Also, from what I learned here, I am also replacing my 2 x 6 mm2 wire which I had run but not connected, with size 16 from my generator 32 AMP wall outlet to a second safety cut about 15 meters away. Probably overkill, but I want to squeeze every bit of power from everything, and have minimal resistance.

[gandalf12]

You never use braided wire for mains cables always solid core. Do not use braided it is a very bad choice. The reason is one or more of the strands can break. This will increase the heat dissipation in the cable and can lead to a fire.

Mains cable is almost ALWAYS braided. Where are you from?

It is always solid core.

[bankruatsteve]

You never use braided wire for mains cables always solid core. Do not use braided it is a very bad choice. The reason is one or more of the strands can break. This will increase the heat dissipation in the cable and can lead to a fire.

Mains cable is almost ALWAYS braided. Where are you from?

It is always solid core.

It would be interesting to know where you believe that to be true? In Thailand it obviously is not except for the "upcountry" homes on 5/15 and 4mm2 mains.

As Crossy pointed out, solid core isn't even available for the larger sized cable.

[Gary A]

First you have to understand the cable differences. You have solid, stranded and braided. For long runs they recommend solid because it supposedly conducts better, For short runs they prefer stranded because it is easier to work with. I have only seen braided on battery grounds.

[bankruatsteve]

First you have to understand the cable differences. You have solid, stranded and braided. For long runs they recommend solid because it supposedly conducts better, For short runs they prefer stranded because it is easier to work with. I have only seen braided on battery grounds.

OK - semantics aside, I think the argument is about mains consisting of one solid core or multiple solid cores entwined. Crossy, what's the correct term for that? Anyway... mains are NOT usually solid core. They are <the other kind>.

[Crossy]

The word is "stranded", unfortunately it is also used for flexible cables with many very fine strands which is not suitable for fixed wiring.

[Crossy]

You never use braided wire for mains cables always solid core. Do not use braided it is a very bad choice. The reason is one or more of the strands can break. This will increase the heat dissipation in the cable and can lead to a fire.

Mains cable is almost ALWAYS braided. Where are you from?

It is always solid core.

As note earlier Gandalf you make this statement with zero backup information, where is this the case and can you quote a regulation / document that states the same?

I have rolls up to 6mm² which are solid copper, the 10mm² is seven strand as is the 16 and 25, I don't have any bigger in mains cable. I do have 35mm² welding cable which has a lot of very fine strands to make it flexible but I wouldn't let it near mains.

What about this stuff http://www.bangkokcable.com/product/backoffice/file_upload/131004_2-450!750V%2070C%2060227%20IEC%2002.pdf available up to 240mm² which has a lot of 0.5mm strands?

[gandalf12]

You never use braided wire for mains cables always solid core. Do not use braided it is a very bad choice. The reason is one or more of the strands can break. This will increase the heat dissipation in the cable and can lead to a fire.

Mains cable is almost ALWAYS braided. Where are you from?

It is always solid core.

As note earlier Gandalf you make this statement with zero backup information, where is this the case and can you quote a regulation / document that states the same?

I have rolls up to 6mm² which are solid copper, the 10mm² is seven strand as is the 16 and 25, I don't have any bigger in mains cable. I do have 35mm² welding cable which has a lot of very fine strands to make it flexible but I wouldn't let it near mains.

What about this stuff http://www.bangkokcable.com/product/backoffice/file_upload/131004_2-450!750V%2070C%2060227%20IEC%2002.pdf available up to 240mm² which has a lot of 0.5mm strands?

Wiring regulations 17 th edition for 63A incomer. A lot of things are available for specific applications but this post is about a home installation

Edited May 20, 2016 by gandalf12

[Crossy]

Wiring regulations 17 th edition for 63A incomer. A lot of things are available for specific applications but this post is about a home installation

Interesting, I do have a copy of the 17th but since I've not done any UK wiring for close on 30 years I've not read it end to end.

Better quote the particular reg so I can look it up.

EDIT TLC Direct have double insulated 6181Y meter tails in various sizes https://www.tlc-direct.co.uk/Main_Index/Cable_Index/Tails_Meter_New/index.html

"Conductor: Stranded Plain Annealed Copper" to BS6004 http://www.clevelandcable.com/technical-documents/technical-sheet-13.pdf