Lighting

Defects

Probable causes for the defect

Design for Maintainability (DfM) Guidelines

• Voltage dip if cable between lamp and fused splitter is too long or a heavy motor without reduced voltage starter is in same supply line.
• Exhausted lamp life. Need replacement.
• No over current protection device (fuse / circuit breaker) provided.

Construction

Maintenance

• Shadow casting by over-decorative luminaire.
• Lumen outputs of lamps are inadequate..
• Luminaire spacing is too high. Usually such mismatch occurs when the luminaire can not be shifted according to new interior layout
• Covered by dirt, dust, and grime. Poor maintenance or design of luminaire is prone to collect dust.
• Reduced lamp life with time – no regular replacement.

Construction

Maintenance

• Connection of lamp and corresponding switch is not proper. Lights controlled by 2, 3 or 4 way switch mainly suffers from such coordination issues.
• Blown lamp is not replaced.
• Metal halide lamps upon voltage drop take few minutes to restart.

Construction

Maintenance

• Wear and tear with time.
• Exposure to direct weather condition.

• Ensure that lighting design will improve energy and sustainability objectives of the building.
• Specify a centralised lighting control system that allows easy monitoring; or automate the system with a proper control strategy.
• Ensure that:
  — the lighting control is readily accessible. 
• — lamp efficacies and ballast energy performance should meet the latest Minimal Energy Performance Standard (MEPS).
  — lighting power density is calculated for the building and, that it meets the lighting power budget in SS 530:2014 (see also ANSI/ASHRAE/IES Standard 90.1-2016).
  — Calculate daylighting as per BS ISO 10916:2014

Construction

• Conform to the recommended illumination levels for office areas and task activities as per SS 514:2016 (see also CSA Z412-2000 (R2016), ISO 8995-1:2002/Cor 1:2005).
• Comply with specifications for luminaires, for general requirements and tests (SS IEC 60598-1:2016).
• Maintained illuminance depends on the maintenance characteristics of the lamp, the luminaire, the environment and maintenance programme (ISO 8995-1:2002/Cor 1:2005, SS 531-1:2006 (2013)).
• Display and ornamental lighting should be separately controlled.

Maintenance

• Conduct routine checking of adequate lighting levels and maintain adequate lux for appropriate activities in accordance to users’ needs and statutory guidelines (CSA Z412- 2000 (R2016), ISO 8995-1:2002/Cor 1:2005, SS 531-1:2006 (2013), SS 514:2016).
• Practice proper housekeeping by dusting off and cleaning lamp surfaces.
• Conduct regular inspection of light fittings and replace if burnt-out.
• Consider group re-lamping if lamps in the same batch are failing.
• Conduct routine check on transformers and drivers of luminaires.
• Check exterior lights for corrosion, torn cables, compromised watertight seals and discolouration; take remedial action where needed.

Burnt ballast of blown lamp

• Flickering lamps.
• One of the paired lamps is removed or blown. If it is not replaced for a long time, ballasts get overheated from spark.

Construction

Maintenance

• Loose fitting in the ballast causes vibration.
• Vibrations get amplified by large radiating surface of luminaires. Good quality products are tested to pass such design defects.

Construction

Maintenance