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PIS-CS-016/Earthing & bonding

More copper does not always mean safer

More copper was not automatically more safety.

Ras El HekmaResidential3 min read
Conductor function, routing and justified sizingEngineered approach for PIS-CS-016. Identify the function of each conductor and connection. Size for fault duty, clearing time and mechanical requirements. Retain necessary margin and verify thermal/protection performance. Conceptual teaching detail, not an as-built drawing or construction instruction. © PIS Engineering Academy · All rights reserved.PIS ENGINEERING / CASE 016Conductor function, routing and justified sizingENGINEERED APPROACHFLOOR BOARDFLOOR BOARDFLOOR BOARDSIZE BY DUTYFAULT CURRENTCLEARING TIMEFUNCTIONMECHANICALSection shown symbolically; no project conductor sizes implied.1231Identify the function of eachconductor and connection.2Size for fault duty, clearingtime and mechanicalrequirements.3Retain necessary margin andverify thermal/protectionperformance.READ THE DETAILEquipment, joints and current-path interfaces are shown in context.Conceptual teaching plate · no project dimensions or acceptance limits impliedPIS / REV 03© PIS Engineering Academy · All rights reserved

Engineering concept / vector field note

01

The field problem

Premium Residential — Ras El Hekma

A TN-S development used very large internal bonding conductors between floors and local equipment, creating major cost and routing impact.

why the obvious answer can be misleading

Protective and bonding conductor sizing must follow their actual duty: fault current, disconnection time, minimum mechanical requirements and bonding function. Oversizing without calculation can add cost without proportional safety benefit.

02

Why it failed

Protective and bonding conductor sizing must follow their actual duty: fault current, disconnection time, minimum mechanical requirements and bonding function.

Oversizing without calculation can add cost without proportional safety benefit.

03

Follow the engineering

Switch between the field condition and the engineering concept. Trace the path and examine what changes.

Inspect the engineering detail

Conductor function, routing and justified sizingEngineered approach for PIS-CS-016. Identify the function of each conductor and connection. Size for fault duty, clearing time and mechanical requirements. Retain necessary margin and verify thermal/protection performance. Conceptual teaching detail, not an as-built drawing or construction instruction. © PIS Engineering Academy · All rights reserved.PIS ENGINEERING / CASE 016Conductor function, routing and justified sizingENGINEERED APPROACHFLOOR BOARDFLOOR BOARDFLOOR BOARDSIZE BY DUTYFAULT CURRENTCLEARING TIMEFUNCTIONMECHANICALSection shown symbolically; no project conductor sizes implied.1231Identify the function of eachconductor and connection.2Size for fault duty, clearingtime and mechanicalrequirements.3Retain necessary margin andverify thermal/protectionperformance.READ THE DETAILEquipment, joints and current-path interfaces are shown in context.Conceptual teaching plate · no project dimensions or acceptance limits impliedPIS / REV 03© PIS Engineering Academy · All rights reserved

Case 016 · Engineered approach

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Conductor function, routing and justified sizingEngineered approach for PIS-CS-016. Identify the function of each conductor and connection. Size for fault duty, clearing time and mechanical requirements. Retain necessary margin and verify thermal/protection performance. Conceptual teaching detail, not an as-built drawing or construction instruction. © PIS Engineering Academy · All rights reserved.PIS ENGINEERING / CASE 016Conductor function, routing and justified sizingENGINEERED APPROACHFLOOR BOARDFLOOR BOARDFLOOR BOARDSIZE BY DUTYFAULT CURRENTCLEARING TIMEFUNCTIONMECHANICALSection shown symbolically; no project conductor sizes implied.1231Identify the function of eachconductor and connection.2Size for fault duty, clearingtime and mechanicalrequirements.3Retain necessary margin andverify thermal/protectionperformance.READ THE DETAILEquipment, joints and current-path interfaces are shown in context.Conceptual teaching plate · no project dimensions or acceptance limits impliedPIS / REV 03© PIS Engineering Academy · All rights reserved

Scroll to inspect. Numbered details match the notes below the drawing. Conceptual geometry; use the case text for the engineering requirements.

What changes

Recalculate each conductor by function and governing fault duty; retain larger sizes only where the calculation, mechanical requirement or project standard justifies them.

Teaching schematic · not to scale© PIS Engineering Academy · All rights reserved
04

Correction & verification

Recalculate each conductor by function and governing fault duty; retain larger sizes only where the calculation, mechanical requirement or project standard justifies them.

Verification recorded in the case

  • Confirm protection and thermal withstand after value-engineered sizing.
  • Record as-built topology and connection points.
  • Repeat the measurement or functional test under a defined condition.
  • Confirm continuity and mechanical integrity of the corrected path.
  • Document instrument/setup, environmental condition and test method.
  • Close the NCR/case only when evidence supports the conclusion.
References & project context

References are reproduced from the PIS casebook. Select the governing edition and project acceptance criteria before using them for a design. The diagrams explain the concept, rather than define construction dimensions.

IEC 60364-5-54; project fault-level calculations.

PIS reviewed field handbook · PIS-CS-016

View the original social card
05

The engineering lesson

Value Engineering removes unjustified margin — not required safety.

Take the lesson into your next design review.

Keep exploring

Connected lessons.

All cases
Foundation ring and natural structural down pathsEngineered approach for PIS-CS-013. Coordinate a closed foundation ring or engineered mesh. Connect and verify the reinforcement used as natural conductors. Inspect and test defined points before concrete conceals them. Conceptual teaching detail, not an as-built drawing or construction instruction. © PIS Engineering Academy · All rights reserved.PIS ENGINEERING / CASE 013Foundation ring and natural structural down pathsENGINEERED APPROACHFOUNDATION PLAN + REINFORCEMENT CONTINUITYClosed ring / mesh connected to verified structural paths.1231Coordinate a closedfoundation ring or engineeredmesh.2Connect and verify thereinforcement used as naturalconductors.3Inspect and test definedpoints before concreteconceals them.READ THE DETAILEquipment, joints and current-path interfaces are shown in context.Conceptual teaching plate · no project dimensions or acceptance limits impliedPIS / REV 03© PIS Engineering Academy · All rights reserved
13

Earthing & bonding

A foundation earth is a network

A foundation earth is a network, not a straight line on one side of the building.

New Alamein3 min
Equipotential bonding around a rooftop poolEngineered approach for PIS-CS-027. Connect accessible conductive parts to the local bonding concept. Coordinate the local network with PE, LPS and pool electrical design. Verify continuity before finishes conceal the connections. Conceptual teaching detail, not an as-built drawing or construction instruction. © PIS Engineering Academy · All rights reserved.PIS ENGINEERING / CASE 027Equipotential bonding around a rooftop poolENGINEERED APPROACHPOOL PEROOFTOP POOL / SIMULTANEOUSLY ACCESSIBLE METALCoordinate local bonding with the pool, PE and LPS design.1231Connect accessible conductiveparts to the local bondingconcept.2Coordinate the local networkwith PE, LPS and poolelectrical design.3Verify continuity beforefinishes conceal theconnections.READ THE DETAILEquipment, joints and current-path interfaces are shown in context.Conceptual teaching plate · no project dimensions or acceptance limits impliedPIS / REV 03© PIS Engineering Academy · All rights reserved
27

Earthing & bonding

Local bonding around rooftop pools

The external LPS stopped at the roof. The touch-risk problem started at the pool.

High-rise pools3 min
A coordinated network across pillars and kiosksEngineered approach for PIS-CS-037. Coordinate distributed local electrodes with a continuous network. Give each installed component a justified function and duty. Define whether acceptance is individual or system-level. Conceptual teaching detail, not an as-built drawing or construction instruction. © PIS Engineering Academy · All rights reserved.PIS ENGINEERING / CASE 037A coordinated network across pillars and kiosksENGINEERED APPROACHPILLAR APILLAR BKIOSK CCOORDINATED DISTRIBUTED NETWORKInterconnected acceptance describes the network, not one isolatedelectrode.1231Coordinate distributed localelectrodes with a continuousnetwork.2Give each installed componenta justified function andduty.3Define whether acceptance isindividual or system-level.READ THE DETAILEquipment, joints and current-path interfaces are shown in context.Conceptual teaching plate · no project dimensions or acceptance limits impliedPIS / REV 03© PIS Engineering Academy · All rights reserved
37

Earthing & bonding

Distributed earthing, justified by topology

Three earth pits were specified where the site could barely fit one.

Galala3 min
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