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#181153 - 09/23/08 08:26 PM Wiring Systems in IRAQ
Joe Tedesco Offline
Member

Registered: 10/07/00
Posts: 3325
Loc: Boston, Massachusetts USA
I will go to IRAQ soon.

I want to discuss the wiring systems in IRAQ, here's a picture that we can discuss.

Color codes, grounding and bonding, equipment, and fittings, etc., are all somewhat of a problem there, so if you recognize the items in the picture or want to add comments please do so.

For those of us who will be deployed to IRAQ soon it is hoped that these discussions will remain on target avoiding political comments.





_________________________
Joe Tedesco, NEC Consultant

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#181168 - 09/24/08 06:01 AM Re: Wiring Systems in IRAQ [Re: Joe Tedesco]
Hutch Offline
Member

Registered: 05/27/02
Posts: 383
Loc: South Oxfordshire, UK
Looks like the 'not so old' British phase colours - red, yellow, blue plus black for neutral. No bonding of neutral to earth on customer side of transformer. I remember seeing somewhere on this forum, many years ago (From GW1), photos of Britsh square pin sockets + some pretty dodgy wiring IIRC.

Best of luck Joe - keep safe.

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#181209 - 09/25/08 08:01 AM Re: Wiring Systems in IRAQ [Re: Hutch]
Joe Tedesco Offline
Member

Registered: 10/07/00
Posts: 3325
Loc: Boston, Massachusetts USA
Thanks for your comments, I am interested in hearing from anyone who has worked behind the wire in IRAQ. The electricians who work on the systems there are confronted will different color codes and systems.
_________________________
Joe Tedesco, NEC Consultant

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#181236 - 09/26/08 07:15 AM Re: Wiring Systems in IRAQ [Re: Joe Tedesco]
pauluk Offline
Member

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
That basic look of that panel is very familiar from the British perspective, but it appears to have a few twists and quirks compared to what we're used to here.

As Hutch noted, the busbars at the top of the MCCB are marked to the "old" British system, but it appears as though there are some newer cables in place as well, although the colors seem to be a little muddled.

We've discussed the color code changes at length in other threads, but for reference here are the standard U.K. systems which appear to be used -- at least some of the time -- in Iraq:

The "old" system, standard until a couple of years ago:

Phase A = red
Phase B = yellow
Phase C = blue
Neutral = black

The new system:

Phase A = brown
Phase B = black
Phase C = gray
Neutral = blue

Earth/ground = green/yellow in both cases (or green on older installs).

The feeder appears to be the newer 4-core cable with brown/black/gray/blue, but with black & blue swapped over so that they can retain black as neutral and blue as a phase. The branch cables exiting the panel on the lower right plus the 3-phase circuit on the far left appear to have been treated the same way.

Looking at the smaller 1-ph circuits on the left, I'm not certain, but it looks as though they might be American standard black/white/green.

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#181258 - 09/27/08 04:09 AM Re: Wiring Systems in IRAQ [Re: pauluk]
Joe Tedesco Offline
Member

Registered: 10/07/00
Posts: 3325
Loc: Boston, Massachusetts USA
Thank you Paul!

I appreciate the information and understand that it will not be easy for electricians who will be working and inspecting in IRAQ who are familiar with only with US color coding schemes.
_________________________
Joe Tedesco, NEC Consultant

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#181259 - 09/27/08 04:47 AM Re: Wiring Systems in IRAQ [Re: Joe Tedesco]
Joe Tedesco Offline
Member

Registered: 10/07/00
Posts: 3325
Loc: Boston, Massachusetts USA
 Originally Posted By: Joe Tedesco
I will go to IRAQ soon.

I want to discuss the wiring systems in IRAQ, here's a picture that we can discuss.

Color codes, grounding and bonding, equipment, and fittings, etc., are all somewhat of a problem there, so if you recognize the items in the picture or want to add comments please do so.

For those of us who will be deployed to IRAQ soon it is hoped that these discussions will remain on target avoiding political comments.




Just in from New Zealand:

"Nothing too odd about this setup, it follows fairly standard European approaches, however normally you don’t see so much sand in the box.

This is the bottom chunk of a panelboard showing the main breaker and the earth (left) and neutral bars. Supply will be 400V phase to phase, or 230V phase to neutral. European practice does not have any oddities like corner grounding or high legs.

Color codes: green/yellow is earth, and then what you usually get is black for neutral, with the phase colors being red, yellow, blue. There is a new set of color codes now mandatory in Europe so expect confusion to come.

The cables out the bottom of the panel are Steel Wired Armored - SWA. Have a gander here for some pictures. Available from two core to seven core, commonly seen as two, three or four core. SWA is tough cable; you can drive a rubber tired truck over it, but I gather a tank will rip it to shreds. SWA isn't a flexible cable but it is non-rigid.

There is a kit used to terminate the cable as can be seen used.

The steel wire armor is frequently used as the only earth conductor. for a circuit Be aware that as the earth conductor is steel not copper then the earth impedance may be too high to operate a MCB, see the last bit here on RCDs. In many installations a separate single earth wire is run in parallel with the SWA armor. In contrary to this, for single-phase circuits, sometimes three core SWA is used with one core as the earth. This is normally wired as phase red, neutral blue, earth yellow. Note that the yellow core should have green / yellow tape or heat shrink placed over it to denote change of use.

The presentations on the right are correct in that the phase conductors appear to go up to the breakers. On the left it looks like an American has wired it up with black being used for phase (y'know hot is black), red for neutral, which is exactly wrong, and how people get hurt.

The earth arrangement seems to be a bit of a nightmare in Iraq. European wiring would normally use TN-C-S, which is how this panel appears to be wired, and how the USA does it, except that in the USA the neutral/ground bond is in the service entrance equipment under the control of the electrician, but elsewhere the neutral/earth bond is provided by the PoCo before the meter. The issue is (based on what I have read here and elsewhere) that sometimes the bond is poor or missing, leading to dangerous situations. The recommendation (and indeed what the BS regs require) is to use a RCD (a/k/a GFCI but with a higher trip current and slower response) as a main breaker to protect both against shock current and to protect wiring under short circuit conditions when the short circuit current is insufficient to trip the MCBs quickly enough.

Given that in Iraq the electrical systems all seem to be based on European (and in particular UK) practice, it is odd that American electricians are widely used. Its not that there is anything fundamentally different or anything wrong with American electricians, electricity is electricity, but there are lots of details in practical application.

The British wiring regs (which is what installations should conform to) is tiny compared to the NEC. It covers much less stuff, allowing much greater latitude on the part of the electrician. But it does have the important stuff, and the tables in the back for determining wire sizes etc, which are, of course different to the NEC. You'll need to get used to "sq. mm", rather than AWG.

You might like to buy a book, something like the $60 (but looks good) Commentary on IEE Wiring Regulations.

To be compliant with the regs you need more test equipment than most American electricians seem to have. Testing and certification is a requirement, not an option. Many manufacturers produce a "16th edition test kit".

And get a volt stick, simple non-contact thing, and shove it in anywhere you are planning on shoving your fingers. 240V hurts lots more than 120V!"
_________________________
Joe Tedesco, NEC Consultant

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#181275 - 09/29/08 04:06 AM Re: Wiring Systems in IRAQ [Re: Joe Tedesco]
SteveFehr Offline
Member

Registered: 03/19/05
Posts: 1192
Loc: Chesapeake, VA
 Originally Posted By: Joe Tedesco
Thank you Paul!

I appreciate the information and understand that it will not be easy for electricians who will be working and inspecting in IRAQ who are familiar with only with US color coding schemes.
Joe, I don't want to get specific due to security concerns, but I do have some familiarity with our forward deployed systems. One thing you will find a lot of are built-up european-style boxes a lot like what you see in this photo. I say built-up because they're a box with breakers mounted in it, with no bus-bar; all the wires jumper from breaker to breaker. Breaker lugs are used as splice points with many many wires terminated in each lug. Some are daisy-chained one-to-the-next off the inputs with one cable rated for 100A feeding 3 or 4 100A breakers, etc. Few panels have dead-fronts. Hurts my good american NEC-minded sensibilities, but it's not feasible to upgrade the entire middle east to NEC 2008 and panels like this are simply not a high-priority compared to all the other risks out there. These wires are in open air, though, although overloaded, are not likely to burst into flames even in the worst case scenario, and even if they did, the fire would be contained in the box and unlikely to kill anyone. I've replaced a few, but left others alone. Pick your battles carefully, the lives of our service members are counting on it. I'd probably leave the panel in this photo alone.

Also, remember, if it's 50Hz, NEC doesn't apply ;\)

Green/yellow striped is always ground. No bare copper in europe, it's going to be green/yellow. I don't even try to keep up with the 3-phase color scheme anymore as if differs from country to country and has been revised several times. ("Holy crap, look at the current on the neutral!! ... oh wait, white is a phase conductor here? doh!") I just try to stay consistant with that's there ;\) And don't be surprised to see ground wires run separately; it's common practice to run the ground wire outside of the main cableway, and to jumper/bond equipment completely independantly of the main raceway. So if you think a circuit is missing a ground, look elsewhere, it may be simply be coming in from the opposite direction. Or, it may be missing completely- safety all to frequently seems to fall secondary to "making it work".

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#181277 - 09/29/08 06:48 AM Re: Wiring Systems in IRAQ [Re: SteveFehr]
Joe Tedesco Offline
Member

Registered: 10/07/00
Posts: 3325
Loc: Boston, Massachusetts USA
Thank you!

This is good information and you make good sense! Please let me know if you are there now or if we can continue these discussions here or through email or a PM.
_________________________
Joe Tedesco, NEC Consultant

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#181289 - 09/30/08 08:14 AM Re: Wiring Systems in IRAQ [Re: SteveFehr]
Texas_Ranger Offline
Member

Registered: 12/17/01
Posts: 2343
Loc: Vienna, Austria
 Quote:
I say built-up because they're a box with breakers mounted in it, with no bus-bar; all the wires jumper from breaker to breaker. Breaker lugs are used as splice points with many many wires terminated in each lug.

Most regulations leave it to the breaker manufacturer to state whether double-lugging is acceptable or not. Typically breakers are rated for up to two wires of the same cross-section!

Bus bars are used as an independent part of the panel assembly, usually provided by the breaker manufacturer. They are usually a set of three copper bars with spade connectors for every breaker enclosed in plastic. Covers for empty breaker spaces as well as both ends of the bars are required. Where double pole breakers or RCDs are installed, the phase tab of the bus bar is removed in the field, either sawed off or broken with pliers (some manufacturers provide breaks there). These bus bars need to match the installed breakers and are typically rated for up to 63 amps. Solid or stranded wire links are perfectly acceptable too but take more time to install. At least Hager and ABB provide bus bars that just snap into the breakers. Non-matching breakers can be installed but usually don't fit the bus bar and have to be connected using jumper wires.

Hardly any country has mandatory phase colors, usually anything but yellow/green can be used, where a neutral is present it has to be blue (though this seems to have been omitted in Iraq and replaced with black).

Grounding can either be achieved by bonding to the neutral (at any point of the given install, depending on age and location) even without a local ground rod (TN-C system) or only to a local ground rod (TT). TN-C systems can have the neutral bond anywhere from the service entrance to the last receptacle. In most countries the neutral ahead of the bond (called PEN for protective earth neutral) is required to have a cross section of no less than 10 sq. mm. to minimize the risk of a broken neutral (which would result in all grounded surfaces becoming hot in case of an unbonded ground). It is regarded as good practice to bond as early as possible though.

Typical checks include isolation resistance, ground and loop impedance and RCD trip currents/times.

Voltage drop is regarded as a big issue, especially in Germany. Total voltage drop from the meter to the last fixed device is limited to 3% and in theory an electrician would be required to calculate the cross section of any(!) wiring run based on mechanical strength, wire ampacity (depending on cross section and type of installation, e.g. non-metallic cable or wires in conduit embedded in insulation, wires in conduit in solid walls or surface mounted conduit, non-metallic cable directly embedded in solid walls,...) and voltage drop.
In everyday work there are rules of thumb valid to wire runs no longer than 30 meters, above a quick voltage drop calculation becomes adviseable.

RCDs have a maximum current on the name plate and if either the upstream OCPD or the sum of the downstream OCPDs exceeds the rating the have to be protected by a suitably rated OCPD!
Some countries have differing requirements regarding this point, Switzerland allows for protection exceeding the RCDs rating based on the assumption not all loads will be run simultaneously, Austria on the other hand requires the RCD nominal current to be equal or greater than 1.6 (main fuse) or 1.45 (main breaker) times the nominal current of the priotecting OCPD.

That's all I can think of now.

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#181291 - 09/30/08 08:51 AM Re: Wiring Systems in IRAQ [Re: Texas_Ranger]
SteveFehr Offline
Member

Registered: 03/19/05
Posts: 1192
Loc: Chesapeake, VA
The problems in the sandbox are not the code-compliant ones, regardless of what codes they're compliant with. And really, not the ones installed by any competant electrician- regardless of the nation of origin, and even if it's not strictly by code. The real problem are the hack jobs done by people who know nothing about eletricity and even less about safety. It's like DIY by idiots, like ungrounded receptacles hooked up with #18 speaker wire laying loose on the ground. These are the ones that kill people.

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