Good afternoon everyone.

I will be dedicating this thread to sharing information about my sojourn into the City of Gold for the past 3 years and highlight of some of the amazing projects I did during these years.

Sometimes late 2018 I got referred by a client to his partner, a Syrian engineer. At that time, his company was handling a government owned project in Dubai (due to NDA I won't be sharing the pics here), which happened to be a car holding facility similar to one of the electrical projects that was executed by us some years back ago in Ogun state though a book publishing facility.

That was how my journey into city of Gold took off.

Over the course of my stay there, I completed the designs and electrical installation of numbers of projects, both government and individually owned.

Working in Dubai was the most challenging and rewarding experience thus far in my career. Dubai as a world class city has a unified set of standards for construction that promotes sustainable development and innovation in building design.
Electrically, aside adherence to IEE regulations.
The city's Electricity and Water Authority (Dewa) has a set out rules and regulations that must be adhered to and it has a strict policy of monitoring and inspection of completed construction project.
So first thing I did was sort for the Dewa regulations as this will be our guide to keeping up with this set out standards.
Unlike what is obtainable here in Nigeria, IEEE regulations is not enough to the task ahead.

One of the project that I'd be sharing is the electrical and low current system implementation of a pedestrian bridge in an outskirt of the city centre.

This project was designed to have an extented concrete ramp since the design is quite different from other bridges that normally comes with Lifts and stair.
So the ramps were precasted without giving room for the routing containment for the lightings and other service outlets wire and cable.
With the bridge itself 100% steel structure, means of the wires and cables routing from the DB and IT room located under the ramp will be our major challenge.

Keeping in mind that as per Dewa regulations
"Non- metallic conduit shall not be used where exposed to outside ambient
temperature, where it may be affected by chemicals to cause deterioration in its
construction, in plant rooms, lift motor rooms and lift shafts"
With the above recommendations the containment has to be a metallic material.

Here.

Part of the drawing.. I'm finding it hard uploading pictures.

On the 2nd day of site visit, we're able to install all the sleeves for the meter cabinet, DBs and the RMS Panel.

*All the underground containment is of grade A rated heavy duty UPVC ducts materials.

Good morning everyone, i have not ben able to update the thread for sometime now.
Had serials of meeting for the past days and lots of mobilisation ongoing for our next project in Ibadan.

Still on the bridge..
The boring for the earthing was done. This part of Dubai is roughly 20m above sea level. As per DEWA regulations

".......the consumer's 'Main Earth electrode' shall be installed as near to the main distribution board as possible. Wherever, more than one 'Earth electrode' is installed, within the consumer premises, these shall be spaced at minimum 6 metres apart. .

For load centres located laterally 50 meters or more from the main DBs, additional back-up earthing may be required near the same.

Chemical treatment of soil has environmental implications and should not be considered as a long term solution in order to meet a specified level of resistance, apart from the risk of corrosion to the earthling system. Coke breeze should also not be used due to its highly corrosive nature.

The main earth electrode resistance shall not exceed 1 ohm, for each incoming DEWA supply/MDB.
The resistance from any point of the Earth continuity conductor to the Main Earth electrode shall not exceed 0.5 ohm.
The consumer's earth electrode resistance and continuity of ECCs shall be periodically checked and maintained as above, to ensure consumer safety.

The lightning protection earthing shall be separate from the earthing of the incoming DEWA supply/MDBs and shall not be interconnected and a minimum distance of 7 meters shall be maintained between the earthing inspection pits."

In other to get resistance of less than 1 ohm then the earth rode will have to literally go over 20 metres deep.
The only way to achieve this, is by boring, not without the approval from DM because of the services underground. After which the copper rod will be slotted deep down into the ground.
So here we have 2 earthing system for the electrical and 1 for the steel structure.

1. Boring machine..
2. Earth tester.. Less down resistance of 0.5 ohm

Drawings..

1. Bridge

1. SS trunking for the containment.
2. Terminated earthing pot
3. GI pipes adapted to the trunking.