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| {{Menu Index}} __NOTOC__ | | {{Menu Index}} __NOTOC__ |
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| == [[General Contents |General Contents ]] == | | == [[The basic functions of LV switchgear|The basic functions of LV switchgear]] == |
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| ==== Methodology and definition ==== | | ==== Electrical protection ==== |
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| ==== Overcurrent protection principles ==== | | ==== Isolation ==== |
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| ==== Practical values for a protective scheme ==== | | ==== Switchgear control ==== |
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| ==== Location of protective devices ==== | | == [[The switchgear |The switchgear]] == |
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| ==== Conductors in parallel ==== | | ==== Elementary switching devices ==== |
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| == [[Practical method for determining the smallest allowable cross-sectional area of circuit conductors|Practical method for determining the smallest allowable cross-sectional area of circuit conductors]] == | | ==== Combined switchgear elements ==== |
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| ==== General ==== | | == [[Choice of switchgear |Choice of switchgear]] == |
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| ==== General method for cables ==== | | ==== Tabulated functional capabilities ==== |
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| ==== Recommended simplified approach for cables ==== | | ==== Switchgear selection ==== |
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| ==== Busbar trunking systems ==== | | == [[Circuit-breaker|Circuit-breaker]] == |
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| == [[Determination of voltage drop|Determination of voltage drop]] == | | ==== Standards and description ==== |
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| ==== Maximum voltage drop limit ==== | | ==== Fundamental characteristics of a circuit-breaker ==== |
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| ==== Calculation of voltage drop in steady load conditions ==== | | ==== Other characteristics of a circuit-breaker ==== |
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| == [[Short-circuit current|Short-circuit current]] == | | ==== Selection of a circuit-breaker ==== |
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| ==== Short-circuit current at the secondary terminals of a MV/LV distribution transformer ==== | | ==== Coordination between circuit-breakers ==== |
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| ==== 3-phase short-circuit current (Isc) at any point within a LV installation ==== | | ==== Discrimination MV/LV in a consumer’s substation ==== |
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| ==== Isc at the receiving end of a feeder in terms of the Isc at its sending end ====
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| ==== Short-circuit current supplied by an alternator or an inverter ====
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| == [[Particular cases of short-circuit current|Particular cases of short-circuit current]] ==
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| ==== Calculation of minimum levels of short-circuit current ====
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| ==== Verification of the withstand capabilities of cables under short-circuit conditions ====
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| == [[Protective earthing conductor|Protective earthing conductor]] ==
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| ==== Connection and choice ====
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| ==== Conductor sizing ====
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| ==== Protective conductor between MV/LV transformer and the main general distribution board (MGDB) ====
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| ==== Equipotential conductor ====
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| == [[The neutral conductor|The neutral conductor]] ==
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| ==== Sizing the neutral conductor ====
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| ==== Protection of the neutral conductor ====
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| ==== Breaking of the neutral conductor ====
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| ==== Isolation of the neutral conductor ====
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| == [[Worked example of cable calculation|Worked example of cable calculation ]]<br> ==
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