OTHER ASPECTS
5
EMERGENCY
LIGHTING
5 1
Most electronic ballasts are suitable for use in emergency lighting
installations. Distinction must, however, be made between centralised
and decentralised emergency lighting. Provided the correct voltages
are applied, electronic ballasts can be used in centralised installations.
When talking about a decentralised emergency lighting set-up, many
different configurations are possible. In general the emergency
converter must have a four-pole switch-over relay to ensure that the
wiring between the HF ballast and the lamp is completely shut off
when the emergency lighting is in operation. Interference from the
emergency converter to the HF ballast is then out of the question.
Some emergency lighting installations equipped with a three-pole
switch-over relay can also be used in combination with HF electronic
ballasts, but this has to be checked and warranted by the emergency
lighting supplier and installer.
HF BALLASTS AND DIMMING
5 2
Fluorescent lamps can be dimmed with dimmable HF electronic
ballasts, such as the Philips HF-REGULATOR types.
Philips HF-REGULATOR ballasts can be controlled by a 1-10V DC
input from various types of regulating systems.
In Fig. 15, an example is shown of an electronic potentiometer
(LPS 100) regulating the dimming level via the +/- DC input on the
HF-REGULATOR ballast.
It can be seen that a total number of up to 100 HF-R ballasts
powered by different phases can be controlled (see Fig. 16).
The control wiring must be dealt with like 230V wiring.
For more information on the installation of different control systems,
contact your local sales agent.
Fig. 15. LPS 100 potentiometer.
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