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Quote
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.


I don't see red used as a neutral in there. That's why I was a little hesitant earlier, given the variance in cameras and monitors, plus the discoloration from dirt and sand, but those single-phase circuits look like standard American colors to me, with white as neutral. Does anyone else see those neutrals as red? confused

Originally Posted by Texas_Ranger
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).


British IEE Regulations (now BS7671) have stipulated the phase colors for decades -- Red/yellow/blue for phases (red/white/blue up until 1964), and a single-phase circuit derived from a 3-phase system must be red, regardless of the phase to which it is connected. A single-phase feeder to a sub-panel is an exception, and may use a "hot" conductor of the appropriate matching phase color.

Substitute brown/black/gray for the revised colors now in force with similar conditions and exceptions, i.e. all single-phase branches to use brown phase except sub-feed to final distribution panels which may use matching black or gray phase color.

I quote these for reference since Iraqi systems seem to be loosely based on the British Standard, but as the blue/black swap on the new cables shows, there are clearly some twists.

Quote
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.


Again, I am not familiar with anything in Iraq beyond the various installations we've discussed here in the past, but for what it's worth Joe, you might like to look at the diagrams of the various British grounding methods which illustrate the basic arrangement of TN-S, TN-C-S, and TT. These diagrams were based on a single-phase 240V residential supply fed from the usual 240/415 wye distribution system, but the basic grounding arrangements are equally applicable to 3 phase services (and all three variants can be found on 3-ph commercial services in the U.K.):

Diagram #1: TN-S
Separate ground-fault current path back to source.

Diagram #2: TN-C-S, a.k.a. PME
Closely resembles standard American system with installation grounded to supply neutral, except that the bond is made right at the service head. There are still separate neutral & earth busbars at the main panel, with the neutral bar isolated.

Diagram #3: TT
Ground-fault current path is via a local rod and the earth only -- An arrangement not permitted by the NEC, of course. Due to the high loop impedance which results, an RCD (GFI) is almost always required.

Quote
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


That is the requirement under British regs. - Minimum 10 sq. mm bond for PME.


Joined: Aug 2001
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Re the SWA cable, it looks like this:

[Linked Image]

The glands which are used to terminate it come in two different types. There is a 2-part gland which just has a single nut which screws onto the bush to clamp the wire armor securely for the earth and hold the cable in place:

[Linked Image]

The 3-part gland has an extra section which then screws on behind and contains a weather seal for outdoor use:

[Linked Image]



Joined: Oct 2000
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Thanks pauluk

Do you know about this publication? Is it a good source?

http://www.reuters.com/article/pressRelease/idUS100451+20-Feb-2008+BW20080220


Joe Tedesco, NEC Consultant
Joined: Oct 2000
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Hello!

I am back home now and plan on spending lots of time here catching up!


Joe Tedesco, NEC Consultant
Joined: Apr 2002
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Joe T!!

Welcome back, from one of the Jersey guys!




John
Joined: Oct 2000
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Thanks! The years do fly buy for sure!


Joe Tedesco, NEC Consultant
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Welcome back. Good to see you stateside.
I hope you have a bunch of good pictures


Greg Fretwell
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