Insulation
2022-01-18
Inspection
- Are non conducting deck coverings, such as non-conducting matts or gratings, being provided at the front of switchboard?
- Are the non-conducting deck coverings suitable for voltage exceeding 220 Volts?
- Do the non-conducting deck coverings extend the entire length of the operating space?
- Are the non-conducting deck coverings of sufficient width?
- Is the insulation matting certified to conform to a minimum 1000 Volts as per European Standards IEC 61111:2009 or equivalent?
- Is the main and emergency switchboard earth fault monitoring operational and free of earthing fault indications?
Special Requirements
- Although minimimum insulation resisitance is 1 MOhm as per Classification Society requireemnts, OCIMF and Rightship require to maintain minimum insulation resisitance more than 5 MOhm and 2 MOhm for 440V and 220V system respectively.
- The alarm settings should be 0.2 MOhm for 220V sysetm and 0.5 MOhm for 440V systems.
Common Poor Practices
- IMD for any distribution indicated an insulation resistance value of less than the required.
- Alarms were not set as required.
- ECR switchboard was not provided with non-conducting deck coverings.
References
European Standards, Live working - Electrical insulating matting. IEC 61111:2009
IMO, International Convention for the Safety Of Life At Sea (SOLAS)
OCIMF, SIRE 2.0
Rightship, Inspection Ship Questionnaire
USCG, 46 CFR 111.30-11- Deck Coverings