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1912

Insulated conductor system U20, U30, U40 - 19699 SELECTION OF CONDUCTORS

Total equivalent continuous current of the installation ( I
DA ): (According to Table 3: The three output-strongest motors plus base loads):(With reduction factors and simultaneousness factorsaccording to 1 e): I
DA = ∑ I
D + ∑ I
G I
DA = (I
NK1 +I
NK2 ) · ƒ
R · ƒ
G I
DA = 143.1 A+ 116.8 A+ 42.8 A+ 16 A+ 8 AI
DA = (369.6 A+ 261.7 A) · 0.7 · 0.8 I
DA = 326.7 AI
DA = 354 A Selection of conductor: U 30/200 C with I
zul = 530 Amax. continuous current (Catalogue value at UT= 35°C)With the ambient temperature of + 40°C a max. current load is calculated: (from Table 5) I
zul 40°C = I
zul · ƒ
T = 530 A· 0.95I
zul 40°C = 504 A> I
DA Effective feed-in length with 3 feeds: Favourable arrangement: l =L10=180 m10= 18 m Max. starting current of the installation ( I
AA ): The three strongest motors acc. to Table 6 (before values fromAs no individual outputs are known, acc. to 3 c) withTable 1) plus base loadstwo cranes the following formula applies (strongest craneSize of output:at the start):1. 110 kW I
A = 1350 A I
AA = (I
NK1 · X +I
NK2 ) · ƒ
R X = 6, because squirrel-cage motor 2. 90 kW I
N = 160 A I
AA = (369,6 A· 6 + 261,7) · 0,7 ca. I
A = 6 · I
N 3. 37 kW I
N = 68 A I
AA = 1736 A 4. Base load 1 I
D = 20 A5. Base load 2 I
D = 12 A I
AA = 1610 A Voltage drop: U = 3 · l · I
AA · Z · ƒ
1 (ƒ
1 = 1.037 at UT= 40°C for U 30/200 C from Table 7) U = 3 · 18 m · 1610 A· 0.195 Ohm · 1.037 U = 3 · 18 m · 1736 A· 0.195 Ohm · 1.0371000 m1000 m U = 10.2 V=^2.5% of 400 V U = 10.9 V=^2.7% of 400 V The voltage drop is thus smaller than 3 % and the chosen current collector line sufficiently dimensioned. Determining of current collector:Crane 1: I
DK1 = 236.6 AI
DK1 = I
NK1 · ƒ
R = 369,6 A/· 0,7I
DK1 = 258.7 A Current collector KDST280/30 with I
zul = 280 Amax. continuous current (Catalogue value at UT= 35°C)For UT= 40°C: I
zul 40°C = I
zul · ƒ
T ƒ
T = 0,97 from Table 5 = 280 A· 0.97I
zul 40°C = 271 A Crane 2: I
DK2 = 168.9 AI
DK2 = I
NK2 · ƒ
R = 261.7 A·0,7I
DK2 = 183.2 A Current collector KDST200/30 with I
zul = 200 Amax. continuous current (Catalogue value at UT= 35°C)For UT= 40°C: I
zul 40°C = I
zul · ƒ
T ƒ
T = 0.97 from Table 5 = 200 A· 0.97I
zul 40°C = 194 A

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