ECN Forum Forums General Topics of the Trade Non-US Electrical Systems & Trades Wiring Systems in IRAQ

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!"