Calculation

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Calculation No. {{ calcvals.CalcNumber }},   Rev: {{ calcvals.Revision }}
Created By: {{ calcvals.CompanyName }},   For: {{ calcvals.ClientCompanyName }}
Project: {{ calcvals.ProjectNumber }}  --  {{ calcvals.ProjectName }} -- {{ calcvals.SubProjectName }}
Cable Num.: {{ calcvals.CableNumber }},   From: {{ calcvals.FromLocation }}, To: {{ calcvals.ToLocation }}
Fast.Engineer

    Calculating...

{{ calcvals.CableNumber }} : Cable Sizing Calcualtion - Three Phase Load

Selected Cable
{{data.Col2}} {{data.Col3}} {{data.Col4}}
(Table 1.1)
Cable Destination
{{data.Col2}} {{data.Col3}} {{data.Col4}}
(Table 1.2)
Cable Source
{{data.Col2}} {{data.Col3}} {{data.Col4}}
(Table 1.3)
Cable Installation
{{data.Col2}} {{data.Col3}} {{data.Col4}}
(Table 1.4)
Calculation Summary
Current Carrying Capacity Cable Loading = {{calcvals.cableLoadingPercent}}%
Voltage Drop Percent Drop = {{calcvals.voltagedroppercent}}%
Short Circuit Withstand Minimum Cable Size is {{ calcvals.minCableCSA | number:3 }} mm² Pass
Earth Fault Loop Impedance Maximum Cable Length = {{ calcvals.maxLengthEarthLoop | number:3 }} meters Pass
** This Calculation was generated by www.Fast.Engineer - Engineering Accurate Instant **
{{ calcvals.CalcNumber }} - Rev: {{ calcvals.Revision }}
Page 1 of 6


Calc: {{ calcvals.CalcNumber }}, Rev: {{ calcvals.Revision }}
Cable #: {{ calcvals.CableNumber }}

    Calculating...

Step 1 :   Cable Current Carrying Capacity


Cable Rated Current
{{data.Col2}} {{data.Col3}} {{data.Col4}}
(Table 2.1)

Derating Data
{{data.Col1}} {{data.Col4}} {{data.Col2}} {{data.Col3}}
(Table 2.2)
Calculating the Combined Derating Factor:

Cable Derated Current Capacity:

The Required Load Current Per Cable:




Check : Review the Cable Current Carrying Capacity
The cable is loaded at: {{calcvals.cableLoadingPercent}}%
Pass - Cable is Ok.
Fail - Cable is overloaded
** This Calculation was generated by www.Fast.Engineer - Engineering Accurate Instant **
{{ calcvals.CalcNumber }} - Rev: {{ calcvals.Revision }}
Page 2 of 6


Calc: {{ calcvals.CalcNumber }}, Rev: {{ calcvals.Revision }}
Cable #: {{ calcvals.CableNumber }}

    Calculating...

Step 1 :   Cable Current Carrying Capacity


Cable Rated Current
{{data.Col2}} {{data.Col3}} {{data.Col4}}
(Table 2.1)

Derating Data
{{data.Col1}} {{data.Col4}} {{data.Col2}} {{data.Col3}}
(Table 2.2)
Calculating the Combined Derating Factor:

Cable Derated Current Capacity:

The Required Load Current Per Cable:




Check : Review the Cable Current Carrying Capacity
The cable is loaded at: {{calcvals.cableLoadingPercent}}%
Pass - Cable is Ok.
Fail - Cable is overloaded
** This Calculation was generated by www.Fast.Engineer - Engineering Accurate Instant **
{{ calcvals.CalcNumber }} - Rev: {{ calcvals.Revision }}
Page 3 of 6


Calc: {{ calcvals.CalcNumber }}, Rev: {{ calcvals.Revision }}
Cable #: {{ calcvals.CableNumber }}

    Calculating...

Step 2 :   Cable Voltage Drop

Looking Up the Cable Impedance:

Referencing standard 'AS/NZS 3008.1.1.2017' for a {{calcvals.MimsVoltage}} {{calcvals.CableType}} {{calcvals.CableFormation}}, three phase cable with {{calcvals.CableInsulation}} insulation and {{calcvals.CableFormation == "Multicore" ? calcvals.MulticoreArrangement : ""}} {{calcvals.Metal}} conductors laid in {{calcvals.SinglecoreArrangement}} at an operating temberature of {{calcvals.MimsTemp}} {{calcvals.CuTemp}}{{calcvals.AlTemp}}℃, finding the smallest cable with an impedance lower than {{calcvals.maxImpedance}} max impedance of {{calcvals.maxImpedance}} Ohm/m, we find that the resistance and reactance for a cable with {{calcvals.conductor}}mm² size conductors is:

{{data.Col2}} {{data.Col3}} {{data.Col4}}
(Table 3.1)
Calculating the Cables Impedance:

Calculate the Actual Voltage Drop:

The Voltage Drop is calculated from the equation


Cable Derated Current Capacity:


Check : Cable Voltage Drop
Pass - Voltage Drop is Ok.

The computed voltage drop equates to {{ calcvals.voltagedroppercent }} % of the supply voltage, this is less than the maximum permissable voltage drop.

Fail - Excessive Voltage Drop

The computed voltage drop equates to {{ calcvals.voltagedroppercent }} % of the supply voltage, which is greater than the maximum permissable voltage drop.

** This Calculation was generated by www.Fast.Engineer - Engineering Accurate Instant **
{{ calcvals.CalcNumber }} - Rev: {{ calcvals.Revision }}
Page 4 of 6


Calc: {{ calcvals.CalcNumber }}, Rev: {{ calcvals.Revision }}
Cable #: {{ calcvals.CableNumber }}

    Calculating...

Step 3 :   Short Circuit Withstand

{{data.Col2}} {{data.Col3}} {{data.Col4}}
(Table 4.1)
Calculate the Minimum Conductor Size:

The Smallest conductor size that can withstand the potential fault current





Check : Review the Cable Short Circuit Capacity
Pass - The {{ calcvals.conductor }} mm2 Cable is large enougth to withstand the potential fault current.
Fail - Cable is undersized for the potential fault current.
** This Calculation was generated by www.Fast.Engineer - Engineering Accurate Instant **
{{ calcvals.CalcNumber }} - Rev: {{ calcvals.Revision }}
Page 5 of 6


Calc: {{ calcvals.CalcNumber }}, Rev: {{ calcvals.Revision }}
Cable #: {{ calcvals.CableNumber }}

    Calculating...

Step 3 :  Earth Fault Loop Impedance

Calculate the Earth Fault Trip Current:
{{data.Col2}} {{data.Col3}} {{data.Col4}}
(Table 5.1)

The earth fault trip current is calculated from the equation


The Maximum Earth Loop Cable Length is calculated from:


Check : Maximum Cable Length for Earth Loop Impedance
Pass - Cable Length is Ok for earth fault loop impedance.
Fail - Cable is too long, and additional earth conductor will be required.

Created By:
{{ calcvals.CreatedBy }}
Sign: __________________
Checked By:
{{ calcvals.CheckedBy }}
Sign: __________________
Approved By:
{{ calcvals.ApprovedBy }}
Sign: __________________
Client Approved By:
{{ calcvals.ClientApprovedBy }}
Sign: __________________
** This Calculation was generated by www.Fast.Engineer - Engineering Accurate Instant **
{{ calcvals.CalcNumber }} - Rev: {{ calcvals.Revision }}
Page 6 of 6