Installation and operating instructions

Rating of automatic line protectors and inrush currents

When the lamps are ignited using choke/starter switching, the lamps ignite sequentially. With ECG switching, all L lamps ignite simultaneously.
If the lamps are switched on at the mains voltage peak, the storage capacitors in electronic control gear systems cause a large, but very brief current surge. In this case the simultaneous loading of these capacitors can result in a larger starting current within the system when ECG units are employed rather than when choke/starter switching occurs.
This means, that the maximum permissible number of luminaires per automatic line protector is reduced (see table). For instance, the maximum permissible number of luminaires for each 10 A automatic protector is reduced from 15 luminaires, each with 2 x 58 W lamps using conventional control gear (CCG) with DUO switching, to 8 luminaires for ECG switching.

When using the values in the table please observe the following:

In ECG operation the load data relates to switching on at peak voltage
The type and characteristics of the circuit breaker:
The specified load from fluorescent lamps and the associated control gear applies to N circuit breakers of Type 5 SN1-6 and 5 SX with B characteristics. If the circuit breaker types with C characteristics are used the number of permitted luminaires for ECG operation can be doubled. (Note in particular VDE 0100 Part 410.)
Circuit breaker design:
The specified loading is for single-pole circuit breakers. When multi-pole circuit breakers are employed (2-pole, 3-pole) the number of permitted luminaires is reduced by 20 %.
Lamp switch-on:
The specified load applies:
- to starting of the relevant number of luminaires in the case of "switch-start operation2
- to the maximum number of luminaires switched (with one switching operation) in the case of "ECG operation"
Circuit impedance:
The specified loading applies with reference to a line impedance 800 mΩ. (This corresponds to a 15 m, 1.5 mm² cable from the distribution board to the first luminaire and a further distance of 20 m to the middle of the circuit). At a line impedance of 400 mΩ, the permitted values are reduced by 10 %, and by 20 % for a line impedance of 200 mΩ.