Instruction manual
14
load distribution)
- unstable power supply (for example some countries in Far East)
2.4.2 Possible Implications
due to Overvoltage
It is called overvoltage, if the supply voltage exceeds the specified voltage
range of an ECG including tolerances.
In any case, overload means more stress to electronic components.
Depending on the magnitude of overvoltage the protective functions of an
ECG can come into effect and turn the ballast off.
In extreme situations overvoltages can even destroy electronic
components.
Therefore, please pay attention to the design of the mains and tolerances
of the Electronic Control Gear when using them.
2.4.3 Undervoltage and its
Reason
Supply voltages can not only deviate to higher values but also to
lower values. If the supply voltage decreases below the value
specified in the technical data of an ECG, we have to deal with
undervoltage.
This may be true for the following points:
• Different loads on the mains side
• Incorrect electric installation
• Unstable power supply
• In some cases when used with emergency generators
2.4.4 Possible Implications
due to Undervoltage
Operating ECG with undervoltage is not as specified. This may result
in the following implications:
• Lamp operation not according to standards Î affecting lamp life
• No safe lamp start, a safe ignition is only guaranteed above supply
voltages of 198 V
• Unstable lamp operation meaning the discharge process of a
fluorescent lamp is not stable
• In order to keep the lamp wattage constant most ECG types are
controlled on the lamp side. In this case, reduced supply voltages
cause much higher currents which may lead to physical stress of
components and to failure of the entire ECG. If supply voltages
deviate significantly from the nominal values, high switching losses
and overload of transistors can occur finally causing ballast failures.
2.4.5 Supply Voltage
QT with 21 mm height
Valid for: QTi and QT…F/CW
Recommended voltage range for
continuous operation
AC voltage 198 V ... 264 V, 50/60 Hz
DC voltage 176 V ... 264 V
Performance at undervoltage
Lamp ignition
U
N
≥ 198 V Î reliable lamp ignition
Voltage drop during operation
U
N
≥ 176V Î operation possible
U
N
< 176 VÎ damage to ECG
possible