Indoor Furnishings User Manual

22
2000-11-07
4.5 Lifetime performance
If the ‘TL’5 lamps are operated on electronic gear, designed accor-
ding to the specifications mentioned in this documentation,at a
3-hour switching cycle (165 minutes on,15 minutes off),the lamps
will have a rated average lifetime of 20,000 burning hours.
Notes on life expectancy curves:
Lamp lifetime is specified as the total number of actual operating
hours under specific operating conditions.Philips ‘TL’5 lamps are
designed for operating with proper preheated electrodes before
lamp ignition is established and in accordance with IEC 60901.This
is to ensure also reliable long life when the switching frequency is
higher than the standard IEC cycle (165 minutes on,15 minutes off).
The published curves give typical average values based on measure-
ments made by Philips Quality Department Lighting based on large
production batches of lamps and tested under laboratory
conditions in accordance with IEC 60901.
In practice, the performance of individual lamps or groups of lamps
may vary from the average.
Lamps are tested in conjunction with commercially available
preheat control gear (ballasts).
The rated average lamp life is the expected time at which 50% of
any large number of lamps reach the end of their individual lives.
Actual operating conditions deviate in most cases from the applied
test conditions.The differences can have a significant influence on
lamp performance.
Switching cycle effects
The rated average lamp life of ‘TL’5 lamps is negatively affected
when the switching frequency is higher than the IEC cycle (165
minutes on,15 minutes off).
The table below gives an indication of the relation between the
amount of switching and the lamp life.
Note: Lifetime figures depend on ballast type.In practice lifetimes can
deviate.
Figure 4.4.1 Life expectancy with a 3-hr switching cycle
50
60
70
80
90
100
Survivals in %
Operating hours
0
5000 10000
15000
20000
Typical values:
5000 hrs: 99%
10000 hrs: 98%
Figure 4.4.2 Lumen maintenance
50
60
70
80
90
100
Lumen in %
Operating hours
0
5000 10000
15000
20000
Typical values:
5000 hrs: 94%
10000 hrs: 92%
15000 hrs: 90%
Operating Lamp life
cycle time
min
115%
100%
90%
80%
690 on,30 off
165 on,15 off
90 on,15 off
45 on,15 off