Basic HTML Version
9/6
Dimensions
Section 10
For use with lighting loads
Miniature
circuit breakers
9
Table 1: fluorescent lighting
Depending on the power supply and the number and types of lighting units, the
table gives the circuit breaker rating based on the following assumptions:
n
Installation in an enclosure with an ambient temperature of 25˚C (derating
coefficient = 0.8)
n
Power of ballast: 25% of tube power
n
Power factor: 0.6 for non-compensated fluorescent lighting. 0.86 for
compensated fluorescent lighting
Circuit breakers mounted in an enclosure with an ambient exterior temperature of
25˚C: derating coefficient = 0.8.
Table 2: high pressure discharge lamps
Table valid for 230V and 400V, with compensated or non-compensated ballast.
Mercury vapour + fluorescent substance
Rat. (A)
P(1)
≤
700W
6
P(1)
≤
1000W
10
P(1)
≤
2000W
16
Mercury vapour + metal halides
P(1) 375W
6
P(1) 1000W
10
P(1) 2000W
16
High pressure sodium vapour lamps
P(1) 400W
6
P(1) 1000W
10
Single phase system: 230V
Three phase + N system: 400V between phases
Types of
Power of
tubes (W)
Number of lighting units per phase lighting unit
Single phase
18
4 9 29 49
78 98 122 157 196 245 309 392 490
non-compensated
36
2 4 14 24 39 49 61 78 98 122 154 196 245
58
1 3 9 15 24 30 38 48 60 76 95 121 152
Single phase
18
7 14 42 70 112 140 175 225 281 351 443 562 703
compensated
36
3 7 21 35 56 70 87 112 140 175 221 281 351
58
2 4 13 21 34 43 54 69 87 109 137 174 218
Two phase 2x18 =
36
3 7 21 35 56 70 87 112 140 175 221 281 351
compensated 2x36 =
72
1 3 10 17 28 35 43 56 70 87 110 140 175
2x58 =
118
1 2 6 10 17 21 27 34 43 54 68 87 109
MCB rating
1 2 6 10 16 20 25 32 40 50 63 80 100
Calculation: non-compensated fluorescent lighting example (star connection)
Number =
(rating x 0.8) (U x 0.6)
(P x 1.25)