Why Good Installations Still Fail — and Fires Start at the Ends of Cables
4
Introduction — cables don’t fail in the middle
When electrical fires or faults occur on ships, investigations rarely find failure mid-cable. Damage almost always occurs at:
- terminations
- glands
- penetrations
- bonding points
- poorly controlled earthing paths
Cabling systems fail where mechanical, thermal, and electrical stresses combine — usually where workmanship and understanding matter most.
Marine cabling is structural, not just electrical
Shipboard cables must withstand:
- vibration
- temperature cycling
- oil contamination
- humidity and salt ingress
- mechanical movement of structure
A cable that is electrically correct but mechanically unsupported will fail. A gland that is watertight but poorly bonded becomes an ignition source.
🔧 Regulatory anchors (explicit)
IEC 60092-350 / 352 / 353 define:
- cable construction
- routing and support
- penetration sealing
- fire performance
SOLAS Chapter II-1 Regulation 45 links poor cabling practices directly to fire risk.
Class surveys increasingly focus on installation quality, not just cable type.
Earthing and bonding — where ships become part of the circuit
Improper earthing causes:
- circulating currents through hull
- corrosion acceleration
- EMC interference
- unreliable protection operation
Ships often use IT systems. Incorrect bonding defeats their fault-limiting purpose and creates hidden current paths.
A ship with poor earthing does not fail electrically — it fails structurally and unpredictably.
EMC — interference that looks like software failure
Electromagnetic Compatibility issues manifest as:
- spurious alarms
- PLC communication dropouts
- sensor noise
- DP reference instability
- unexplained trips
The cause is often:
- poor cable segregation
- incorrect screen termination
- uncontrolled bonding loops
- proximity of power and signal cables
EMC failures are often misdiagnosed as “automation faults”.
🔻 Real-World Case: Engine Room Fire from Cable Termination — MV Maersk Honam (2018)
While the primary casualty aboard MV Maersk Honam was catastrophic fire, investigation findings highlighted:
- electrical cable routing and penetration integrity
- heat and ignition risk from damaged cabling
- propagation pathways through cable runs
Electrical installations did not cause the accident — but they influenced how fire spread and escalated.
Cabling decisions affect survivability long after the initiating event.
Professional ETO mindset
An experienced ETO asks:
- Where does fault current actually return?
- What heats up first under load?
- Are screens terminated correctly — and where?
- What fails if vibration increases?
Cables are not passive. They shape how faults behave.
Knowledge to Carry Forward
Most electrical failures on ships begin at interfaces, not components. Cabling, glanding, earthing, and EMC discipline determine whether faults stay local or become casualties.
A perfect schematic cannot save a bad termination.
Tags
ETO, Marine Cabling, Electrical Glanding, Earthing Bonding, EMC Ships, IEC 60092, Marine Electrical Fires, Installation Quality