Inrush current

Just as in LED light source operation, there are increased inrush currents in discharge lamps due to the construction of the equipment used (cf. chapter In terms of electronic control gear (ECG) for fluorescent lamps, the effects are comparable to those for LED operation. The reason for this is the similarity of the electronic input circuits. In the ECG as well, constant DC voltage is generated by means of energy storage in a condenser, which is then transformed into high-frequency AC voltage for lamp operation. This requires input capacities of identical range in order to make the effects as well as their representation in the ECG data sheets comparable to those of the LED control gear (cf. figure and figure).

Figure 2.47: Example for an excerpt from an ECG data sheet. This data sheet specifies the maximum inrush current caused by the ECG in an electrical installation as well as notes on CB with varying magnetic trip (characteristics B and C).

For magnetic control gear (CCG or LLCG) with parallel-compensated circuit types, the sum of condensers connected in parallel represents a capacitive load which causes an elevated inrush current here as well.

Regarding mains switch load, magnetic trip of circuit breakers (CB) as well as possibilities for limiting inrush current, the same conditions which apply to LED drivers also apply to ECG (cf. chapter Where switches or circuit breakers in lighting installations with magnetic control gear need replacement, it is recommended to use the technical specifications of the components to be replaced as a guideline.