15

System

pro M compact ®

Miniature circuit-breakers

S 200/S 200 M series

Use of S 200/S 200 M miniature circuit-breakers in direct current circuits 60 VDC/125 VDC

In DC systems up to 60 VDC or, as the case may be, series connection up to 125 VDC, customary S 200/S 200 M series MCBs can be used.

Polarity does not need to be taken into consideration, the outgoing circuit may be implemented from above or below the device.

For higher direct voltage up to 440 VDC devices of the S 280 UC series must be used.

Example for max. permissible voltages between conductors depending on the number of poles and type of connection.

Fusing of lighting currents

1. Filament lamps and fluorescent lamps

The following table indicates the maximum number of fluorescent lamps that can be protected with a single-pole miniature circuit-breaker.

In the case of multipole MCBs, the value is reduced by 20 %. Tripping charcteristic type C allows for light currents up to the rated current

of the MCB,

for fusing of:

filament lamps

fluorescent lamps

a) non-compensated

b) shunt compensated (cos

ϕ = 0.95)

c) electronic load

2. High-pressure discharge lamps

Starting current: ca. 1.7 x lamp current

Recovery time: ca. 3 ... 5 min.

According to the type of lamp, line impedance and start-stop torque, the so-called rectifier effect may occur which superimposes the

starting current of the lamp for some half-waves.

In the most unfavorable circumstances, inrush currents of 15 times of the lamp nominal current may ensue.

To avoid nuisance tripping, MCBs with K-type characteristic should not carry loads higher than 0.6-fold of the lamp current. The load factor

indicated refers to the least favorable case (proximity to transformer, low line impedances).

Examples for different voltages between a conductor and earth where voltages between conductors are identical:

➀

electronic ballast: twin-lamp style, jointly switched number of lamps

Characteristic/

non-compensated

shunt compensated

electronic ballast

➀

rated current

conventional ballast

conventional ballast

18/20 W

36/40 W

58/65 W

18/20 W

36/40 W

58/65 W

18/20 W

36/40 W

58/65 W

10

27

23

15

32

32

20

18

18

8

16

43

37

24

51

51

33

26

26

12

20

53

46

30

64

64

41

33

33

15

25

66

58

37

82

82

53

42

42

19