194
The Lighting Handbook
Maintenance lighting systems
Today, the maintenance lighting installa-
tions decisive factor installation’s
balance costs.
All these factors describe the decrease in
illumi
nance. the
respec
tive time maintenance, the various
causes the decrease illuminance must
be identified.67 implies a
new illuminance level Enew 750 lx. The maximum each case 1,
corresponding the new value.
Em:
maintained illuminance =
maintenance value illuminance
(1) Enew Maintenance factor components
– Lamp luminous flux mainten. factor LLMF
– Lamp survival factor LSF
– Luminaire maintenance factor LMF
– Room maintenance factor RMF
Causes illuminance decrease
– Ageing lamps
– Failure lamps
– Soiling luminaire
– Soiling room
The maintenance factor includes
4 components
(2) LLMF LSF LMF RMF
Benefit high MF
– lower luminaire investment costs
– reduced energy costs
Benefit low MF
– low maintenance costs
– longer maintenance intervals
Please note: lower maintenance factor,
illuminance may constantly dimmed the
maintenance value save energy (maintenance
control).
Options for improving the
maintenance factor
– lamp replacement already before the lamp
service life ends (LLMF/LSF )
–
immediate replacement lamps case
of failure (LSF 1)
– use closed luminaires (LWF7 )
– more frequent room cleaning (RWF7 )
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.
According the formula below (1), light-
ing level required 500 standard
maintenance factor 0
