Instruction manual

19
2.9 ECG Imprint
2.10 Reliability
Besides component specification and quality their failure rate is significantly
related to the operating temperature.
Electronic Control Gear of OSRAM are designed in that way, that a failure
rate of less than 2 Promille per 1,000 operating hours is expected if
operation takes place at the maximum permitted case temperatur (t
c
).
2.11 Resistance to Frequent
Switching
The resistance to frequent switching of Electronic control gear is based on
possible lamp starts per day. Multiplied with the lamp life professional ECG
with preheat start reach more than 100.000 switching cycles.
This information is important for combinations with occupancy sensors as
this is one of the most popular applications for frequent switching of the
lamp-ECG system.
2.12 ECG Lifetime
The ECG lifetime depends on the operating temperature and failure rate of
the electronic components. Extreme overheating can destroy electronic
components in a short period of time and cause the ECG to fail. There
exists an exponential relationship between the failure rate of electronic
components and their thermal and also electrical behaviour.
An indication about the maximum recommended ambient temperature of a
luminaire is given by the imprinted measuring point tc at which each ECG
reaches its maximum recommended case temperature. The t
c
-temperature
of an OSRAM ECG is closely linked to its temperature of electronic
components. For example, when the maximum recommended tc-
temperature of 70 °C is reached, a QUICKTRONIC control gear for
operation of T5/∅ 16 mm-fluorescent lamps is expected to last
50,000 hours with a failure rate of max. 10 %. This value equals a failure
rate of 2 ‰ per 1,000 operating hours. Due to the exponential dependence
on temperature and failure rate of electronic components exceeding the
recommended tc-temperature reduces the ECG lifetime dramatically. On
the other hand, if the ECG temperature remains below the limit the lifetime
is extended. As a rule of thumb, every 10 °C below the imprinted
temperature value double the ECG’s lifetime and every 10 °C surpassing
the tc-value cut the service life in half.
The measuring temperature t
c
is an important parameter for both the safety
approval for a luminaire according to EN 60598 and the service life of an
Thermal Behaviour
Cut-Off-Technology
End-of-Life Safety-shut-
down
Functional Earth terminal
µProzessor inside
Lamp wiring including
max. cable lengths
Thermal Behaviour
Cut-Off-Technology
End-of-Life Safety-shut-
down
Functional Earth terminal
µProzessor inside
Lamp wiring including
max. cable lengths
Cut-Off-Technology
End-of-Life Safety-shut-
down
Functional Earth terminal
µProzessor inside
Lamp wiring including
max. cable lengths