DS5840 datasheet(40/82 Pages) OSRAM

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3. Circuits

Economical long-life light sources with plug-in bases.

Compact Fluorescent Lamps OSRAM DULUX®

Technical Guide

3.3

Operating on

dc sources

Compact fluorescent lamps cannot be operated from DC sources with conven-

tional control gear.

Most ECGs are DC-compatible. The dc voltage must be around the rated mains volta-

ge of 230 V. See information supplied by ECG manufacturers.

Special ECGs such as OSRAM ACCUTRONIC ® are available which allow OSRAM

DULUX® S/E, D/E, T/E, L and F lamps to be operated from DC sources which do not

correspond to rated mains voltages (such as the 12 V, 24 V or 48 V sources found in

emergency lighting systems, vehicles and caravans).

In these cases, power is supplied by a battery or batteries. In continuous operation,

the dc voltage must not drop below 11 V (AT 7-9/12 L) or 23 V (AT 7-9/24 L) otherwise

the lamps will be constantly operating in underload mode. This will damage the lamp

electrodes (sputter effect at the electrode).

Manufacturers of suitable control gear for different lamp wattages and battery volta-

ges are listed in 10.2 and 10.3.

Changeover units (emergency luminaires with internal changeovers, known as battery

packs) are offered. These feed the lamps directly on emergency power supply and

interrupt the system circuit between the CCG or ECG and the lamps. These change-

over units for emergency lighting must reliably comply with the parameters for prehea-

ting and for operating the lamps. If operated continously, control gear for emergency

lighting can generate a dc component that may damage the lamp electrodes (under-

load operation of the lamps). This underload operation with a DC component causes

electrophoresis in the lamp. As a result, the mercury migrates from one electrode to

another if the lamp is operated continously. This greatly reduces the life of the lamp. In

this case, OSRAM therefore cannot guarantee the life of the lamp.

3.3.1 Suitable OSRAM

ECGs for DC

operation

OSRAM offers the following ECGs under the ACCUTRONIC® name for dc operation.

(See Lighting Programme).

DS5840 Datasheet(PDF) 40 Page - OSRAM GmbH