Changes

== Introduction – Cable sizing in pv systems ==

== Introduction – Cable sizing in PV systems ==

In designing a solar or electrical system, it is important to pay attention to the cable size selection as this is a critical part of the overall system. Properly selecting and sizing all the cables in a solar system is crucial to ensure adequate system performance and safety compliance.  

In designing a solar or electrical system, it is important to pay attention to the cable size selection as this is a critical part of the overall system. Properly selecting and sizing all the cables in a solar system is crucial to ensure adequate system performance and safety compliance.  

=== Step 2 – De<span lang="EN-US"></span>termine the method of installation for the cables ===

=== Step 2 – De<span lang="EN-US"></span>termine the method of installation for the cables ===

The ampacity of a conductor is the current carrying capacity which depends significantly on the method of installation and obviously the section. An illustration of some of the many different methods of installation is provided below. These methods are grouped with code letters A to G having the same characteristics relative to the current-carrying capacities of the circuit:

The ampacity of a conductor is the current carrying capacity which depends significantly on the method of installation and obviously the section. An illustration of some of the many different methods of installation is provided below. These methods are grouped with code letters A to G having the same characteristics relative to the current-carrying capacities of the circuit:

[[File:IEC60364-5-52 P1.png|center|frameless]]

[[File:IEC60364-5-52 P1.png|center|frameless|506x506px]]

[[File:IEC60364-5-52 P2.png|center|frameless]]

[[File:IEC60364-5-52 P2.png|center|frameless|412x412px]]

 

The above table is part of table A.52.3 of IEC 60364-5-52

The above table is part of table A.52.3 of IEC 60364-5-52

==== Buried cables ====

==== Buried cables ====

[[File:IEC60364-5-52 P4.png|center|thumb|The above table is the current-carrying capacity in ampere with reference to table B.52.1. of IEC 60364-5-52.]]

[[File:IEC60364-5-52 P4.png|center|thumb|The above table is the current-carrying capacity in ampere with reference to table B.52.1. of IEC 60364-5-52.|563x563px]]

Following the example in step 1 with calculated current as 20.45 A, assuming the cable is to be unburied with 3 number of loaded PVC conductors, then the size of cable to be selected in 4mm² which corresponds to 23A from the table above.  

Following the example in step 1 with calculated current as 20.45 A, assuming the cable is to be unburied with 3 number of loaded PVC conductors, then the size of cable to be selected in 4mm² which corresponds to 23A from the table above.  

* T<span lang="EN-US"></span>ype of circuit: Single phase or three-phase

* T<span lang="EN-US"></span>ype of circuit: Single phase or three-phase

T<span lang="EN-US"></span>he voltage drop is then calculated from the table as :  

T<span lang="EN-US"></span>he voltage drop is then calculated from the table as :

  K x I_B x L

  K x I_B x L

The column motor power “cos ϕ = 0.35” of the table below may be used to compute the voltage drop occurring during the start-up period of a motor.  

The column motor power “cos ϕ = 0.35” of the table below may be used to compute the voltage drop occurring during the start-up period of a motor.  

[[File:IEC60364-5-52 P6.png|center|thumb|426x426px]]

[[File:IEC60364-5-52 P6.png|center|thumb|573x573px]]

Again, following the same example with 4mm² cable selected, assuming the cable is to run for 30m (0.03km) connected to resistive load (cos ϕ = 1), then the voltage drop for copper can be calculated as:

Again, following the same example with 4mm² cable selected, assuming the cable is to run for 30m (0.03km) connected to resistive load (cos ϕ = 1), then the voltage drop for copper can be calculated as: