Day-care Facility and Administration Building at MoD … always calculated in a workmanlike manner. Dimensioning of Protection conductors The standard CEI 64-8 par. 543.1 takes into

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Wiring diagram and calculation

SIZE CLASSIFICATION

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00 First Issue 16 / 01 / 2017

Day-care Facility and Administration Building at MoD Headquarters

KABUL, AFGHANISTAN

REPORT ON THE CALCULATION PERMORMED

Calculation of load currents

The calculation of load currents is executed following the classic formula:

IP

k Vb

d

ca n

cos

where:

kca = 1 mono-phase or two-phase system, two active conductors;

kca = 1.73 three-phase system, three active conductors.

If the network is in direct current, then the power factor cos is equal to 1.Using the maximum value (module) of Ib, phase currents are calculated in vector notation (real andimaginary) with the formulas:

cos

cos

cos

I I e I jsin

I I e I jsin

I I e I jsin

bj

b

b

j

b

b

j

b

1

2

2 3

3

4 3

2

3

2

3

4

3

4

3

The voltage vector Vn is assumed aligned with the axis of real numbers:

V V jn n 0

The power of dimensioning Pd is given by the product:

P P coeffd n

where coeff is equal to the factor of use for terminal units or to the contemporaneity factor for thedistribution units.The power Pn, however, is the nominal power of the load for terminal units, ie, the sum of the loadsdownstream (Pd downstream) for distribution units (vector sum).

The reactive power of terminal units is calculated by the formula:

Q Pn n tan

whereas for distribution units the reactive power is calculated as vector sum of downstream nominalreactive powers (Qd downstream).

The power factor for distribution units is evalueted too, with:

Page 2 of 16

cos cos tan

arc

Q

Pn

n

Cable dimensioning

The criterion for the dimensioning of cables is such as to ensure the protection of conductors tooverload currents.According to standard CEI 64-8/4 (§ 433.2), in fact, the protective device must be coordinated withthe conductors in order to verify the conditions:

zf

znb

IIb

IIIa

45.1)

)

By condition a) is necessary to size the cable based on the rated current of the upstream protection.With current Ib, therefore, is determined the rated current of the protection (according to thenormalized values) and with this last one is calculated the proper cable section.The cable dimensioning respects the following cases:

lines without protection derived from a main line protected against overload with a suitabledevice which can also ensure the protection of derived lines;

line that feeds several derivations individually protected against overloads, when the sum oftheir rated currents protective devices does not exceed the current capacity Iz of the of themain line.

The calculation of the section is carried out using the proper laying tables. The seven tables used are:

IEC 448; IEC 364-5-523 (1983); IEC 60364-5-52 (PVC/EPR); IEC 60364-5-52 (Mineral); CEI-UNEL 35024/1; CEI-UNEL 35024/2; CEI-UNEL 35026; CEI 20-91 (HEPR).

In Medium Voltage, the management of the calculation splits according to the choosen table: CEI 11-17; CEI UNEL 35027 (1-30kV).

They bring in addition to the current Iz depending on the type of cable insulation, the type of layingand number of conductors, also report the methodology for evaluating the coefficients ofdowngrading.The minimum cable carrying current is calculated as:

II

kz

nmin

where the coefficient k is intended to downgrade the cable and consider the following factors:

Page 3 of 16

type of conductor material; type of insulation; number of conductors in proximity including any parallel; user rating downgrade.

The section is chosen so that its current capacity (multiplied by k) is greater than the Iz min. Any

parallels are calculated assuming that all have the same section, length and type of laying (see 64.8under par. 433.3), considering the minimum current capacity as a result of the sum of the individualcapacities (downgraded by coefficient of downgrade by proximity).The condition b) does not require verification, for the switches that meet standard CEI 23.3 have arelationship between conventional triggering current If and rated current In a lesser of 1.45 and isconstant for all calibrations below 125 A. For industrial equipment, however, the CEI 17.5 and IEC947 require that this ratio can vary according to the rated current, but it must be less than or equal to1.45.It therefore appears that, according to law, the condition b) is always verified.The lines sized with this criterion, therefore, are protected against overcurrent.

Joule integral

From section of the conductors of the cable comes the computation of the Joule integral, which is themaximum specific energy allowed by cable,:

I t K S2 2 2

The K constant is given by the standard 64-8/4 (par. 424.3) for phase and neutral conductors,whereas the paragraph 64-8/5 (par. 543.1) for protection conductors. K rely on material type andinsulating type.La costante K viene data dalla norma 64-8/4 (par. 434.3), per i conduttori di fase e neutro e, dalparagrafo 64-8/5 (par. 543.1), per i conduttori di protezione in funzione al materiale conduttore e almateriale isolante. For cables with mineral insulation standards are currently being studied, theaforementioned paragraphs, however, report in the comments some conservative values.

The K values reported by standard (par. 434.3) for phase conductors are

Copper cable with PVC insulation: K = 115Copper cable with rubber G insulation: K = 135Copper cable with ethylene-propylene rubber G5-G7 insulation: K = 143Copper cable L serie coated with thermoplastic material: K = 115Copper cable L serie naked: K = 200Copper cable H serie coated with thermoplastic material: K = 115Copper cable H serie naked: K = 200Aluminum cable with PVC insulation: K = 74Aluminum cable with G, G5-G7: K = 87

The K values for unipolar protection cables (par. 543.1) tab. 54B:

Copper cable with PVC insulation: K = 143Copper cable with rubber G insulation: K = 166Copper cable with ethylene-propylene rubber G5-G7 insulation: K = 176Copper cable L serie coated with thermoplastic material: K = 143Copper cable L serie naked: K = 228Copper cable H serie coated with thermoplastic material: K = 143

Page 4 of 16

Copper cable H serie naked: K = 228Aluminum cable with PVC insulation: K = 95Aluminum cable with rubber G insulation: K = 110Aluminum cable with ethylene-propylene rubber G5-G7 insulation: K = 116

The K values for multipolar protection cables (par. 543.1) tab. 54C:

Copper cable with PVC insulation: K = 115Copper cable with rubber G insulation: K = 135Copper cable with ethylene-propylene rubber G5-G7 insulation: K = 143Copper cable L serie coated with thermoplastic material: K = 115Copper cable L serie naked: K = 228Copper cable H serie coated with thermoplastic material: K = 115Copper cable H serie naked: K = 228Aluminum cable with PVC insulation: K = 76Aluminum cable with rubber G insulation: K = 89Aluminum cable with ethylene-propylene rubber G5-G7 insulation: K = 94

Dimensioning of Neutral conductorsThe standard CEI 64-8 par. 524.2 and par. 524.3 takes into account that the neutral cross-section, formultiphase circuits, could have a section less than the phase cross-section whether the followingconditions are fulfilled:

the phase conductor has a section greater than 16 sq mm; the maximum current that could flow in the neutral conductor has to be less than the capacity

current of it; section of the neutral conductor is at least equal to 16 sq mm if the conductor is made of

copper and 25 sq mm if the conductor is aluminum.

For monophase or multiphase circuits with phase cross-section less than 16 sq mm if copper or lessthan 25 sq mm if aluminum, the neutral conductor has to have the same phase cross-section.In order to help the design, it is possible to choose among three neutral conductor designing options,as indicated:

considering the phase cross-section; considering the phase-neutral carrying currents ratio; considering the neutral carrying current.

The first criterion is to determine the cross section according to the following limitations imposed bystandard:

S mm S S

S mm S mm

S mm S S

f n f

f n

f n f

16

16 35 16

35 2

2

2 2

2

:

:

:

The second criterion is to set the ratio between phase conductor and the neutral conductor carryingcurrents, and the program will determine the neutral section according to the carrying current.The third criterion is to size the conductor taking into account the load current flowing in the neutralas a phase conductor.The sections of the neutral, however, assume different values than the methods just mentioned,

Page 5 of 16

always calculated in a workmanlike manner.

Dimensioning of Protection conductors

The standard CEI 64-8 par. 543.1 takes into account two methods for dimensioning protectionconductors:

considering the phase cross-section; considering energy calculation.

The first criterion is to determine the cross section according to the following limitations imposed bystandard:

S mm S S

S mm S mm

S mm S S

f PE f

f PE

f PE f

16

16 35 16

35 2

2

2 2

2

:

:

:

The second criterion determines the carrying current with the integral of the Joule, for which thesection of the protective conductor must not be less than the value determined by the followingformula:

K

tIS p

2

where:- Sp is the protection cross-section (sq mm);- I is the RMS value of fault current that can travel the protective conductor of negligibleimpedance (A);- t is the operating time of protective device (s);- K is a factor whose value depends on the material of the protective conductor, insulation andother parts.

If the formula result is not a standard section, is taken one standard immediately above.For both the criterions, it has to be considered the paragraph 543.1.3 about minimum cross-sections.The paragraph states that the cross-section of a protection conductor not belonging to the supply linecan not be less than:

2,5 mm² if there is a mechanical protection; 4 mm² if there is not a mechanical protection;

You can also determine the section using the ratio between the phase conductor and protectionconductor currying currents.

Calculation of the temperature of the cables

The evaluation of the temperature of the cables rely on the operating current and the rated currentusing the following expressions:

Page 6 of 16

2

2

2

2

z

ncavoambientencavo

z

bcavoambientebcavo

I

ITIT

I

ITIT

expressed in °C.They are derived from the consideration that the working temperature of the cable is proportional tothe power dissipated in it.The coefficient cavo is bound by the type of cable insulation and the type of laying table.

Voltage drop

The voltage drops are calculated vectorially. For each unit is calculated the vectorial voltage dropalong each phase and neutral conductor (if distributed). Between the phases is considered thegreatest voltage drop, returned as a percentage of nominal voltage:

TSRf

k

iiiii nInZfIfZibtdc

,,1

max)(..

where f is the three phases R, S, T;where n is the neutral;where i is one of the k units included in the calculation;

The calculation provides, therefore, the exact value of the approximate formula:

cdt I k IL

R X sinV

b cdt bc

cavo cavo

n

1000

100cos

with:

kcdt=2 for mono-phase systems; kcdt=1.73 for three-phase systems.

The parameters Rcable and Xcable are taken from Table UNEL depending on the type of cable(unipolar/multipolar) and the conductor section, the first of these parameters is reported at 70 °C forcables with PVC insulation, at 90 °C for EPR insulated cables, while the second refers to 50Hz, withthe units in /km.If the operating frequency is different from 50 Hz is set

Xcavof

cavoX 50 .

The voltage drop from upstream to downstream (total) of a unit is determined as the vectorial sum ofthe voltage drops, referring to a single conductor, of the upstream units of the unit in question. Afterthis, is determined the voltage drop as percentage of the rated voltage of the unit in question.The number of phases and the presence of neutral are considered during calculation.Are properly calculated the total voltage drop if there are transformers along the line (for example,MV/LV or LV/LV). In this circumstance, in fact, the calculation of the total voltage drop takes intoaccount the internal transformer VD, and the presence of plugs for the coils ratio adjustment of such

Page 7 of 16

transformers.If at the end of the calculation of voltage drops some units have values greater than those defined, isuseful a routine of optimization to reduce the voltage drop within preset limits (limits given by the CEI64-8 par. 525). The cross sections are forced to higher values, trying to follow a uniform growth, inorder to have all the voltage drops below their limits.

Network Power supply

The knowledge of the network power supply is required to properly calculate the network faultscurrents.Types of power supply can be:

low voltage medium voltage high voltage known impedance direct current

Knowing the sequences parameters at the supply point, you can initialize the network and calculateshort-circuit currents according to IEC 60909-0.These currents will be used when selecting the protections for the verification of breaking capacities.

Low voltage

This can be used when the circuit is fed by the low voltage distribution network, or when the circuitto calculate is connected to an existing distribution board for which the short-circuit currents at thepoint of delivery are known.The required data are:

line-to-line power supply voltage expressed in V; three-phase short-circuit current of the power supply expressed in kA (normally 4.5-6 kA). single-phase short-circuit current of the power supply expressed in kA (normally 4.5-6 kA).

The first two values determines the positive-sequence impedance corresponding to the short-circuitcurrent Icctrif, in m:

ZV

Icctrif

cctrif

2

3

The standard CEI 17-5 provides a table with short-circuit coscc in relation to short-circuit current (in

kA):

Page 8 of 16

50 0 2

20 50 0 25

10 20 0 3

6 10 05

4 5 6 0 7

3 4 5 08

15 3 0 9

15 0 95

I

I

I

I

I

I

I

I

cctrif cc

cctrif cc

cctrif cc

cctrif cc

cctrif cc

cctrif cc

cctrif cc

cctrif cc

cos .

cos .

cos .

cos .

. cos .

. cos .

. cos .

. cos .

from these data we obtain the positive sequence resistance, in m:

R Zd cctrif cc cos

and finally the reactance relative to the positive sequence, in m:

X Z Rd cctrif d 2 2

From the knowledge of single phase fault current lk1, it is possible to derive the zero sequenceimpedance values.Reversing the formula:

20

2

0

21

22

3

XXRR

VI

dd

k

with the assumptionscc

X

Z

X

Rcos

0

0

0

0

, ie the angle of the homopolar components equal to that ofthe direct component, we get:

dcc

k

RI

VR

2cos

3

1

0

1

cos

1200

cc

RX

Correction factor for transformers, IEC 60909-0 (3.3.3)

For transformers with positive power direction, with two coils with and without change under load,we must introduce an impedance correction factor KT such that:

Page 9 of 16

T

T

otTotK

cctTcctK

x

cK

ZKZ

ZKZ

6,0195,0 max

where

n

cctT

PV

Xx

202

is the relative reactance of the transformer and Cmax is taken from Table 1 and is related to the lowvoltage side of the transformer.This factor must be applied both to direct and to homopolar impedance.It should not be applied to autotransformers.

Faults calculation

With the calculation of faults currents, are determined minimum and maximum short-circuit currentsimmediately downstream of the protection of the unit (start line) and downstream units (bottom line).The conditions in which they are determined are:

three-phase fault (symmetric); line-to-line fault (asymmetric); line-to-line-to-neutral fault (asymmetric); line-to-line-to-earth fault (asymmetric); line-to-earth fault (asymmetric); line-to-neutral fault (asymmetric).

The parameters to the sequences of each unit are initialized from the corresponding upstream unit, inturn, initialize the parameters of the line downstream.

Calculation of maximum short-circuit currentsThe calculation is conducted under the following conditions:

a) rated power supply voltage with rated voltage factor Cmax;

b) minimum fault impedance, calculated at a temperature of 20 ° C.

The direct resistance, of the phase and protection conductors, is calculated at 20 °C, coming from theresistance given by the tables UNEL 35023-2009 which is reported at 70 or 90 °C depending on theinsulation. So expressing it in m:

004.01

1

10001000 T

LRR cavocavo

dcavo

Where T is 50 or 70 °C.

Known also from the same tables, the reactance at 50 Hz, if f is the operating frequency, is:

Page 10 of 16

5010001000

fLXX cavocavo

dcavo

we can add these to direct parameters of the upstream unit, thus obtaining the minimum faultimpedance at the end of the unit.For units with bus duct, the components of the positive sequence are:

RR L

dsbarrasbarra sbarra

1000 1000

The reactance is:

5010001000

fLXX sbarrasbarra

dsbarra

For units with known impedance, the components of the positive sequence are the same values ofresistance and reactance of the impedance.

As for the parameters to the zero-sequence, one must distinguish between the neutral conductor andprotection conductor.For the neutral conductor, the omopolar components are obtained with:

R R R

X XcavoNeutro dcavo dcavoNeutro

cavoNeutro dcavo

0

0

3

3

For the protection conductor:

R R R

X XcavoPE dcavo dcavoPE

cavoPE dcavo

0

0

3

3

where the resistances RdvavoNeutro e RdcavoPE are calculated as the Rdcavo.

For units with bus ducts, the zero sequence components of the sequence are distinct from the neutralconductor and protective conductor.For the neutral conductor we have:

dsbarrarosbarraNeut

trodsbarraNeudsbarrarosbarraNeut

XX

RRR

3

3

0

0

For the protective conductor is used the reactance of the fault provided by the manufacturers:

R R R

X XsbarraPE dsbarra dsbarraPE

sbarraPE anello guasto

0

0

3

2

_

The parameters for each unit are added to the parameters, at the same sequence, of the upstreamunit, expressed in m:

Page 11 of 16

R R R

X X X

R R R

X X X

R R R

X X X

d dcavo dmonte

d dcavo dmonte

Neutro cavoNeutro monteNeutro

Neutro cavoNeutro monteNeutro

PE cavoPE montePE

PE cavoPE montePE

0 0 0

0 0 0

0 0 0

0 0 0

To the total values are added the impedances of the power supply.

Known these parameters, are calculated impedances (in m) of three-phase fault:

Z R Xk d dmin 2 2

Line-to-neutral (if neutral is distributed):

Z R R X Xk Neutr in d Neutro d Neutro1 0

2

0

21

32 2om

Line-to-earth:

Z R R X Xk PE d PE d PE1 0

2

0

21

32 2min

From these are calculated the three-phase short-circuit Ikmax , line-to-neutral Ik1Neutromax , line-to-earth

Ik1PEmax and line-to-line Ik2max espressed in kA:

IV

Z

IV

Z

IV

Z

IV

Z

kn

k

k Neutr axn

k Neutr in

k PEn

k PE

kn

k

max

min

om

om

max

min

max

min

3

3

3

2

1

1

1

1

2

Finally from the values of maximum fault current we obtain peak currents (IEC 60909-0 par. 9.1.1.):

I Ip k 2 max

I Ip Neutro k Neutr ax1 12 om

I Ip PE k PE1 12 max

Page 12 of 16

I Ip k2 22 max

where:

102 0 983

. . e

R

Xd

d

Calculation of the peak current for three-phase fault according to IEC 61363-1: Electrical installationsof ships. If required, Ip can be calculated using the simplified method of the standard stated in theparagraph 6.2.5 Neglecting short-circuit current decay. It uses a coefficient k = 1.8 that takes intoaccount the maximum asymmetry of the current after the first half cycle of fault.

Calculation of minimum short-circuit currentsThe minimum short-circuit current calculation is carried out as described in IEC 60909-0 par. 2.5 inrespect of:

the rated voltage is multiplied by the voltage factor of 0.95 (Table 1 of IEC 60909-0); in medium and high voltage the factor is 1; permanent faults with a contribution of the power supply and generators under the permanent

fault state.

For the temperature of the conductors you can choose between: the report CENELEC R064-003, for which resistances are determined to the ordinary service

temperature limit of the cable insulation; the Standard IEC 60909-0, indicating the temperatures at the end of the fault.

Temperatures are given in relation to the type of cable insulation, specifically:

Insulation Cenelec R064-003 [°C] IEC 60909-0 [°C]

PVC 70 160

G 85 200

G5/G7/G10/EPR 90 250

HEPR 120 250

serie L coated 70 160

serie L naked 105 160

serie H coated 70 160

serie H naked 105 160

From these it is possible to calculate the resistance to positive-sequence and zero-sequence relativeto the temperature of the cable insulation:

R R Td dmax max. 1 0 004 20

R R TNeutro Neutro0 0 1 0 004 20 . max

R R TPE PE0 0 1 0 004 20 . max

Page 13 of 16

These, added to the upstream resistance, give the minimum resistance.Evaluated the impedances using the same expressions of maximum fault impedances, we cancalculate the three-phase short-circuit currents and line-to-earth, expressed in kA:

IV

Z

IV

Z

IV

Z

IV

Z

kn

k

k Neutr inn

k Neutr ax

k PEn

k PE

kn

k

min

max

om

om

min

max

min

max

.

.

.

.

0 95

3095

30 95

3095

2

1

1

1

1

2

Choice of protections

The choice of protection shall be performed by the electrical characteristics of the conduits and thenominal values of the fault, in particular properties that are checked are:

rated current, ccording to which the conductor is sized; number of poles; protection type; nominal voltage, equal to unit rated voltage; breaking capacity, whose value must be greater than the maximum fault current at upstream

unit node Ikm max;

magnetic trip current setting, where the maximum value to ensure protection against indirectcontact (without differential) must be less than the minimum fault current at the end of theline (Imag max).

Verification of the short-circuit protection of conductors

According to the standard CEI 64-8 par.434.3 "Characteristics of short-circuit protection devices.",The protection appliances against short circuits must satisfy two conditions:

breaking capacity must not be less than the prospective short circuit current at the point ofinstallation (if there are not adequate protections upstream);

the tripping characteristic must be such as to prevent the temperature of the cable does notexceed, under fault conditions at any point, the maximum allowed.

The first condition is considered when selecting the protections. The second one can be translated inthe relationship:

I t K S2 2 2

ie in case of failure, the specific energy withstand by cable must be greater than or equal to thatallowed through the protection.The CEI 64-8 in par. 533.3 "Choice of protection against short circuits" therefore provides acomparison between the minimum fault currents (bottom line) and maximum (top line) with thepoints of intersection between the curves. The conditions are therefore:

Page 14 of 16

a) The two intersections are:

IccminIinters min (the latter reported in the standard as Ia); IccmaxIinters max (the latter reported in the standard as Ib).

b) The intersection is unique and the protection consists of a fuse:

IccminIinters min.c) The intersection is unique and the protection includes a magnetothermal:

Icc maxIinters max.

The above relations are therefore verified at the fault location. In the case that the fault currents goout the limits of existence of the curve of the protection, check is not performed.

Notes: The representation of the curve of the cable is a hyperbola with asymptotes K²S² and the

Iz of the same. The short-circuit verification of the protection performed by the program consists of a

qualitative test, because the curves are taken from the protection catalog charts and notdirectly from test data, so the accuracy could not be complete.

Verification of selectivity

The selectivity of protections is verified by the overlapping of the curves of intervention. The dataprovided by the overlap, in addition to the chart are:

Current Ia of intervention at the maximum trip time provided by CEI 64-8: so the current isalways given to 5s (valid for the distribution or fixed terminal units) and the current at a timedetermined by the table 41A of the CEI 64.8 par 413.1.3. Providing a range of interventiondefined by a characteristic upper limit and a characteristic lower limit, the trip time is given incorrespondence to the characteristic lower limit. These data are provided for the protectionthe upstream and downstream;

Trip time at the minimum fault current at the end of downstream unit: minimum for theupstream protection (determined on the characteristic lower limit) and maximum for thedownstream protection (determined on the characteristic upper limit);

Ratio of current magnetic trip: of the protections; Current limit of selectivity: ie the current value at the intersection of the characteristic upper

limit of downstream protection and the characteristic lower limit of the upstream protection(CEI 23.3 par 2.5.14).

Selectivity: indicates whether the characteristic of the upstream protection is placed above thecharacteristic of the downstream protection (total) or partially (partial at overload if theintersection between the curves occurs in the thermal range).

Time selectivity: it shows the difference of the protection tripping times at the short-circuitcurrents in which selectivity is verified.

The assessment must take into account the tolerances on the characteristics given by manufacturers.

Whenever possible, the graphic selectivity is ‘helped’ by the table selectivity which values are given bythe manufacturers. These values correspond to the limits of selectivity relative to a pair of protectionsplaced one ahead of the other. The minimum fault current downstream must be less than thisparameter to ensure selectivity.

Standards

Page 15 of 16

Low Voltage Standards: CEI 11-20 2000 IV Ed. Impianti di produzione di energia elettrica e gruppi di continuità

collegati a reti I e II categoria. IEC 60909-0 2001 II Ed.: Short-circuit currents in three-phase a.c. systems. Part 0: Calculation

of currents. CEI 11-28 1993 I Ed. (IEC 781): Application guide for calculation of short-circuit currents in

low-voltage radial systems. CEI 17-5 VIII Ed. 2007 (IEC 60947-2: 2006): Low-voltage swithgear and controlgear. Part 2:

Circuit-breakers. CEI 20-91 2010: Fire retardant and halogen free electric cable with elastomeric insulation and

sheath for use in photovoltaic system (PV). CEI 23-3/1 I Ed. 2004 (IEC 60898-1): Electrical accessories – Circuit breakers for overcurrent

protection for household and similar installations. Part 1: Circuit-breakers for a.c. operation. CEI 64-8 VII Ed. 2012 (IEC 60364): Residential and Industrial premises; Electrical safety. IEC 364-5-523: Wiring system. Current-carring capacities. IEC 60364-5-52: Electrical Installations of Buildings - Part 5-52: Selection and Erection of

Electrical Equipment - Wiring Systems. CEI UNEL 35023 2012 (IEC 60228 III Ed.): Electric cables with rubber and thermoplastic

insulation. Voltage drop. CEI UNEL 35024/1, 1997: Elastomeric and thermoplastic insulated power cables for rated

voltages not exceeding 1000 V a.c. / 1500 d.c. Continuous current capacities for cables laid inair.

CEI UNEL 35024/2, 1997: Mineral insulated power cables for rated voltages not exceeding1000 V a.c. / 1500 d.c. Continuous current capacities for cables laid in air.

CEI UNEL 35026, 2000: Elastomeric and thermoplastic insulated power cables for ratedvoltages not exceeding 1000 V a.c. / 1500 d.c. Continuous current capacities for buriedcables.

NF C 15-100, 2002: Installations électriques à basse tension.

UNE 20460, 2004: Instalaciones eléctricas en edificios. Parte 5: Selecciòn de los materialeseléctricos.

British Standard BS 7671:2008: Requirements for Electrical Installations;

ABNT NBR 5410, Segunda edição 2004: Instalações elétricas de baixa tensão;

Medium Voltage Standards CEI 0-16: Reference technical rules for the connection of active and passive consumers to the

HV and MV electrical networks of distribution Company. IEC 61936-1 2010: Power installations exceeding 1 kV a.c. CEI 11-17 III Ed. 2006: Generation, transmission and public distribution systems of electric

power. Cables lines. CEI-UNEL 35027 II Ed. 2009 (IEC 60287): Power cables with rated voltages from 1 kV to 30

kV. Steday state current rating – Cables laid in air and in ground. CEI 11-35 II Ed. 2004: Guideline for execution of the electric substations MV/LV of the final

customer/user. CEI 17-1 VI Ed. 2005 (IEC 62271-100): High-voltage switchgear and controlgear. Part 100:

High-voltage alternating-current circuit-breakers CEI 17-9/1 (IEC 60265): High-voltage switches. Part 1: Switches for rated voltages above 1

kV and less than 52 kV.

Page 16 of 16

Unit main data Data: 16/01/2017

IbUnit ref-mark Cos ØCircuit Pn Coef. Pd VnSyst. In IzVdT IbLcFormationIkm max

[kW] [kW] [kA] [m] [V] [%] [A] [A] [A]

+Existing MEP Room.DP_DC

U1 8159 0,85 50,13F+N (Distr.) 0,9 400TT n.d.1000,2108,34

VP 1,61 1 13F (Term.) 0,9 400TT 7619,30,20708,34

M 1,61 1 13F (Term.) 0,9 400TT 8119,30,20708,34

PS1 5,771,5 0,8 1,2L3-N (Term.) 0,9 231TT 33161,23403G44,89

PS2 5,771,5 0,8 1,2L3-N (Term.) 0,9 231TT 33161,23403G44,89

PS3 5,771,5 0,8 1,2L3-N (Term.) 0,9 231TT 33160,977303G44,89

PS4 4,811 1 1L3-N (Term.) 0,9 231TT 25160,889203G2.54,89

PS5 3,851 0,8 0,8L3-N (Term.) 0,9 231TT 25160,616153G2.54,89

PS6 0,6422 0,2 0,43F+N (Term.) 0,9 400TT 22160,244155G2.58,34

PS7 7,72 0,8 1,6L3-N (Term.) 0,9 231TT 33320,72153G44,89

PS8 24,115 1 153F (Term.) 0,9 400TT 51320,532154G108,34

PS9 3,851 0,8 0,8L2-N (Term.) 0,9 231TT 33320,467153G44,89

MP1 19,215 0,8 123F+N (Term.) 0,9 400TT 68320,54305G168,34

MP2 1,920,4 1 0,4L3-N (Term.) 0,9 231TT 25100,616303G2.54,89

MP3 1,920,4 1 0,4L2-N (Term.) 0,9 231TT 25100,552253G2.54,89

MP4 3,370,7 1 0,7L1-N (Term.) 0,9 231TT 25100,802253G2.54,89

MP5 3,371 0,7 0,7L2-N (Term.) 0,9 231TT 33100,39123G44,89

MP6 28,96 1 6L1-N (Term.) 0,9 231TT 57320,983153G104,89

MP7 28,96 1 6L2-N (Term.) 0,9 231TT 57321,51253G104,89

L1 3,850,8 1 0,8L1-N (Term.) 0,9 231TT 25101,3403G2.54,89

L2 3,850,8 1 0,8L3-N (Term.) 0,9 231TT 25101,3403G2.54,89

L3 3,850,8 1 0,8L3-N (Term.) 0,9 231TT 25101,3403G2.54,89

L4 3,850,8 1 0,8L2-N (Term.) 0,9 231TT 25101,58503G2.54,89

L5 3,850,8 1 0,8L3-N (Term.) 0,9 231TT 25100,616153G2.54,89

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Unit main data Data: 16/01/2017

IbUnit ref-mark Cos ØCircuit Pn Coef. Pd VnSyst. In IzVdT IbLcFormationIkm max

[kW] [kW] [kA] [m] [V] [%] [A] [A] [A]

L6 3,850,8 1 0,8L1-N (Term.) 0,9 231TT 25101,57503G2.54,89

L7 3,850,8 1 0,8L2-N (Term.) 0,9 231TT 25101,58503G2.54,89

L8 4,811 1 1L1-N (Term.) 0,9 231TT 33101,28503G44,89

FSD 2,40,5 1 0,5L2-N (Term.) 0,9 231TT 33100,746503G44,89

TD 2,40,5 1 0,5L1-N (Term.) 0,9 231TT 33100,74503G44,89

SP1 00 1 0L3-N (Distr.) 0,9 231TT 25100,20504,89

SP2 00 1 0L3-N (Distr.) 0,9 231TT 30100,20504,89

SP3 00 1 0L3-N (Distr.) 0,9 231TT 25160,20504,89

SP4 00 1 0L3-N (Distr.) 0,9 231TT 25160,20504,89

Legend Pn: rated power of the loads downstream the unit. Coef.: coefficient of concurrency (distributions) or of utilization (terminals) Pd: power dimensioning of the unit Ikm max: Maximum fault current, upstream of the unit. Used to determine the protecion's breaking capacity Lc: cable length [m] VdT Ib: voltage drop to current Ib

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Verify Data: 16/01/2017

Coord. Ib<In<IzUnit ref-mark K²S²>I²t Mag. rel.<ImagmaxBC Ind. touchings. VdT Ib

+Existing MEP Room.DP_DC

U1 81<=100 A (Ib < In) n.d. 1000<4147 A16>=8,34 kA Verified 0,21<=6 %

VP 1,6<=19,3 A (Ib < In) n.d.120>=8,34 kA Verified 0,207<=4 %

M 1,6<=19,3 A (Ib < In) n.d.200>=8,34 kA Verified 0,207<=4 %

PS1 5,77<=16<=33 A Verified 160<435,2 A10>=4,89 kA Verified 1,23<=5 %






PS7 7,7<=32<=33 A Verified 320<1029 A50>=4,89 kA Verified 0,72<=4 %



MP1 19,2<=32<=68 A Verified 320<1692 A11,2>=8,34 kA Verified 0,54<=4 %

MP2 1,92<=10<=25 A Verified 100<367,5 A10>=4,89 kA Verified 0,616<=4 %



MP5 3,37<=10<=33 A Verified 100<1226 A10>=4,89 kA Verified 0,39<=4 %



L1 3,85<=10<=25 A Verified 100<279,8 A50>=4,89 kA Verified 1,3<=5 %






Page 2 of 3

Verify Data: 16/01/2017

Coord. Ib<In<IzUnit ref-mark K²S²>I²t Mag. rel.<ImagmaxBC Ind. touchings. VdT Ib



FSD 2,4<=10<=33 A Verified 100<353,3 A50>=4,89 kA Verified 0,746<=5 %

TD 2,4<=10<=33 A Verified 100<353,3 A50>=4,89 kA Verified 0,74<=5 %

SP1 0<=10 A (Ib < In) n.d. 100<4145 A50>=4,89 kA Verified 0,205<=5 %




Legend BC: breaking capacity of the protection Imagmax: maximum magnetic current equal as minimum fault current K²S²>I²t: verify short-circuit of the line ("n.d." means verification is not managed) Reference temperature for the calculation of the minimum short-circuit current by: (CENELEC R064-003) VdT Ib: voltage drop to current Ib

Page 3 of 3

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