1. ح األساسي للتعليم األنصارية رميثة مدرسة وإنجاز إنشاء1بناتبمربض/الفجيرة
Romysaa Alansaryah Primary School for Girls/C1, Merbed/ Fujairah
Volume 2C – Electrical Specifications Page 1 of 4
Electrical – Grounding and Bonding
Revision (0
SECTION 16170
GROUNDING AND BONDING
PART 1 - GENERAL
1.1 SECTION INCLUDES
A. Grounding electrodes and conductors.
B. Equipment grounding conductors.
C. Bonding.
1.2 REFERENCES
A. CP 1013 - Code of Practice - Earthing
B. BS 7671 - Requirements for Electrical Installation
C. BS 7430 - Earthing System Materials & Testing
D. BS 2784 & 970 - Earthing Material, Solid Copper Rods & Accessories
1.3 GROUNDING ELECTRODE SYSTEM
A. Metal underground water pipe.
B. Metal frame of the building.
C. Concrete-encased electrode.
D. Metal underground gas piping system.
E. Rod electrode.
F. Plate electrode.
G. Active electrode.
1.4 SUBMITTALS
A. Submit under provisions of Project requirements.
B. Product Data: Provide data for grounding electrodes and connections.
C. Test Reports: Indicate overall resistance to ground.
D. Manufacturer's Instructions: Include instructions for storage, handling, protection,
examination, preparation and installation of exothermic connectors.
1.5 PROJECT RECORD DOCUMENTS
A. Submit under provisions of Project requirements.
2. ح األساسي للتعليم األنصارية رميثة مدرسة وإنجاز إنشاء1بناتبمربض/الفجيرة
Romysaa Alansaryah Primary School for Girls/C1, Merbed/ Fujairah
Volume 2C – Electrical Specifications Page 2 of 4
Electrical – Grounding and Bonding
Revision (0
B. Accurately record actual locations of grounding electrodes.
1.6 QUALIFICATIONS
A. Manufacturer: Company specializing in manufacturing Products specified in this
Section with minimum five years documented experience.
PART 2 - PRODUCTS
2.1 Earthing system materials shall include the bonding conductors, earth continuity conductors,
150 sq mm earth bar risers, 150 sq mm copper tape, earth pits and wells, earth grid bar,
thermal welding kits and accessories, lugs, terminals, clamps, accessories and other materials
indicated on the drawings and as required by BS 7430 & 7671.
2.2 The nominal cross-sectional area of all earth continuity conductors shall be in accordance with
the IEE Regulations. A separate earth wire shall run along with each armored cable.
2.3 All earth pits, wells and the lightning protection system pits shall be connected together to
create an earth grid extending throughout the site in the form of an earth ring with branches
connected to the equipment and building to be earthed. The earth grid shall comprise copper
earthing cable with green/yellow PVC sheathing.
2.4 All switchboards, metal conduit and trunking systems, metal frames, enclosures, light fittings
and cable sheaths shall be bonded together and connected through 16 sq mm PVC cable to
the earth bar of the appropriate switchboard. Similarly all earth pins and metallic plates of
socket outlets, switches, accessories and enclosures shall be bonded to earth with earth
continuity conductors. Each individual earth path shall be electrically continuous throughout its
length from the farthest pint of the associated part of the system back to the main earth.
2.5 Where separate pieces of apparatus connected to different phases are of necessity erected or
positioned less than two meters apart, an equipotential bonding conductor of single core 70 sq
mm PVC sheathed shall be installed between such pieces of apparatus.
2.6 In the substations, earth grid bus shall be provided and shall connect all the electrical
equipment to the earth pit.
2.7 The star point of the transformers and generators shall be solidly earthed through separate
earth well.
2.8 A 150 sq mm earth bar riser shall be installed in each electrical room and shall be connected
to 6 x 50 sq mm cross-sectional bus bar of suitable length. Earth bar with enough number of
ways and mounted on high impact uPVC channel with disconnecting link provided in each
electrical room and shall be connected to the individual switchboard earth bar through a cable
sized in accordance with IEE Regulations and to the equipotential bonding conductor
connecting metal conduits, trunking systems, metal frames, enclosures, cable sheaths, A/C
duct work pipe riser, etc. Earth bar riser shall be connected to separate earth pits through 150
sq mm copper tape.
2.9 A test connection link shall be provided for testing purpose.
a) Earth Well: Earth well shall be provided only to provide the earth grid at the service
block and at substations. Earth well with 100mm diameter GS pipe shall be driven
up to the water table (approx. depth 45m). An earth bar shall be welded to the top of
the earth well for branch connections. The well shall be protected by a concrete
housing with MS or concrete cover of 250mm x 250mm x 10mm at grade level.
3. ح األساسي للتعليم األنصارية رميثة مدرسة وإنجاز إنشاء1بناتبمربض/الفجيرة
Romysaa Alansaryah Primary School for Girls/C1, Merbed/ Fujairah
Volume 2C – Electrical Specifications Page 3 of 4
Electrical – Grounding and Bonding
Revision (0
b) Earth Pits: 20mm diameter copper earth rod shall be driven to minimum depth of
6m and an earth bar shall be provided to the top of the earth pit for branch
connections. Earth pit shall be protected by concrete housing and MS or concrete
cover at grade level. Bentonite shall be provided in the pit around the earth rod.
2.10 The number and depth of pits shall be sufficient to make the system resistance less than one
ohm.
2.11 For telephone/data and other communication system, provide a minimum 25 sq mm insulated
earthing conductor in raceway from earthing electrode system to each service location,
terminal cabinet, wiring closet, and central equipment location. Terminate the earthing
conductor on earthing bus at wiring closets, service location and central equipment location.
Terminate earthing conductor on cabinet earthing terminal.
2.12 All metal poles supporting outdoor lighting fixtures shall be earthed using earth rod and earth
pit.
2.13 All connectors and splicers shall be made up of bronze.
PART 3 - EXECUTION
3.1 EXAMINATION
A. Verify that final backfill and compaction has been completed before driving rod
electrodes.
3.2 INSTALLATION
A. Install Products in accordance with manufacturer's instructions.
B. Install rod electrodes at locations indicated. Install additional rod electrodes as
required to achieve specified resistance to ground.
C. Provide grounding well pipe with cover at each rod location. Install well pipe top flush
with finished grade.
D. Provide grounding electrode conductor and connect to reinforcing steel in foundation
footing. Bond steel together.
E. Provide bonding to meet Regulatory Requirements.
F. Bond together metal siding not attached to grounded structure; bond to ground.
G. Bond together reinforcing steel and metal accessories in fountain structures.
H. Install transient suppression plate as required.
I. Bond together each metallic raceway, pipe, duct and other metal object entering
space under access floors.
J. Provide isolated grounding conductor for circuits supplying electronic cash registers,
computer room equipment.
K. Equipment Grounding Conductor: Provide separate, insulated conductor within each
feeder and branch circuit raceway. Terminate each end on suitable lug, bus, or
bushing.
4. ح األساسي للتعليم األنصارية رميثة مدرسة وإنجاز إنشاء1بناتبمربض/الفجيرة
Romysaa Alansaryah Primary School for Girls/C1, Merbed/ Fujairah
Volume 2C – Electrical Specifications Page 4 of 4
Electrical – Grounding and Bonding
Revision (0
3.3 INTERFACE WITH OTHER PRODUCTS
A. Interface with site grounding system installed under Project requirements.
B. Interface with lightning protection system installed under Section 16670.
3.4 FIELD QUALITY CONTROL
A. Inspect grounding and bonding system conductors and connections for tightness and
proper installation.
B. Use suitable test instrument to measure resistance to ground of system. Perform
testing in accordance with test instrument manufacturer's recommendations using the
fall-of- potential method.
END OF SECTION
