Earthing & Grounding Systems
Importers in Garissa

25×3 mm to 50×6 mm GI or copper strip covers most grid and bonding runs. Use 25×3 mm for equipment bonding and smaller grids, and 50×6 mm for main substation earthing grids and high-fault-current paths. Check the strip size against the fault current and clearance time using the adiabatic formula in IEC 60364-5-54 Annex A rather than picking a size out of habit.

The coupling, where two rod sections join, is the most vulnerable point in the whole installation. A carbon-steel coupling on a copper-bonded rod creates a bimetallic junction that corrodes far faster than the rod body itself, particularly in aggressive soil. Specify stainless steel or solid copper couplings every time, and treat a mild-steel coupling offered "to save cost" as a warning sign, not a bargain.

Find out who actually does the copper-bonding: an in-house electroplating line, or a subcontractor a few steps removed. Ask for a DFT test report and ISO 9001 certificate as samples. Then ask one pointed technical question, the target resistance at your soil resistivity, and notice whether the answer comes from someone who understands soil chemistry or gets bounced back unanswered. A real manufacturer controls the plating process end to end and backs every claim with paperwork.

IS 3043 clause 4.3 covers pipe electrodes. The minimum bore is 38 mm (1.5 inch NB) with a 4–5 mm wall thickness; 50 mm NB is the more common site choice for better soil contact surface. Standard burial depths are 2.5 m or 3.0 m, but IS 3043 recommends going deeper when soil resistivity is above 50 Ω·m, depth reduces resistance far more effectively than wider bore. An inner perforated pipe (25 mm NB) carries the backfill and watering column. Our standard electrode is 50 mm NB outer, 25 mm NB inner, 3.0 m length, HDG inside and out.