2.1 Noem die instrument wat gebruik word om elektriese energie te meet. 2.2 Noem TWEE voordeel van driefasestelsels bo enkelfasestels. 2.3 Teken 'n netjies benoemde skets wat die spanningsgolwevorme van 'n driefase-WS-ontwikkelingstelsel voorstel. 2.4 'n Driefase sterfverbinde gebalanseerde las word deur 'n driefasegenerator voorsien. Die generator voorsien 20 kVA teen 'n stroom van 25 A. Gegee: $ I_l = 25 \, A $ $ S = 20 \, kVA $ Bereken die: 2.4.1 Lynspanning 2.4.2 Fasespanning 2.5 In 'n driefase-toevoerstelsel is die tweemetermetode gebruik om die insetdrywing na 'n induktiewe las met 'n arbeidsfaktor van 0,8 te meet. Die waardes wat op die instrumente aangedui word, is onderskeidelik 8 kW en 4 kW. Die lynspanning is 380 V. Gegee: $ P_1 = 8 \, kW $ $ P_2 = 4 \, kW $

NSC Electrical Technology Electronics Effect of Alternating Current: 2.1 Noem die instrument wat gebr

2.1 Noem die instrument wat gebruik word om elektriese energie te meet - NSC Electrical Technology Electronics - Question 2 - 2016 - Paper 1

Question 2

2.1 Noem die instrument wat gebruik word om elektriese energie te meet. 2.2 Noem TWEE voordeel van driefasestelsels bo enkelfasestels. 2.3 Teken 'n netjies benoemd... show full transcript

Worked Solution & Example Answer:2.1 Noem die instrument wat gebruik word om elektriese energie te meet - NSC Electrical Technology Electronics - Question 2 - 2016 - Paper 1

Step 1

2.4.1 Lynspanning

96%

114 rated

Answer

To calculate the line voltage ( $V_L$ ), we use the formula:

$S = rac{ ext{sqrt{3}} V_L I_L}{1000}$

Given:

$S = 20 \, kVA$
$I_L = 25 \, A$

We rearrange the formula to solve for $V_L$ :

$V_L = rac{S}{ ext{sqrt{3}} I_L}$

Substituting the given values:

$V_L = rac{20000}{ ext{sqrt{3}} imes 25}$

Calculating this gives:

Approximately $461.88 \, V$ .

Step 2

2.4.2 Fasespanning

99%

104 rated

Answer

To find the phase voltage ( $V_f$ ), we use the relationship between line voltage and phase voltage:

$V_f = rac{V_L}{ ext{sqrt{3}}}$

Substituting the calculated line voltage:

$V_f = rac{461.88}{ ext{sqrt{3}}}$

Calculating this gives:

Approximately $267.67 \, V$ .

Step 3

2.5.1 Totale Spanning

96%

101 rated

Answer

To find the total power ( $P_T$ ), we sum the two powers:

$P_T = P_1 + P_2$

Given:

$P_1 = 8 \, kW$
$P_2 = 4 \, kW$

Substituting the values:

$P_T = 8 + 4 = 12 \, kW$

Step 4

2.5.2 Huidige Berekening

98%

120 rated

Answer

To determine the current ( $I_L$ ) for the load, we use the following formula:

$I_L = rac{ ext{sqrt{3}} V_L I_L ext{Cos}{ heta}}{P}$

Given:

$P = 12000 \, W$
$V_L = 380 \, V$
$ext{Cos}{ heta} = 0.8$

We rearrange the formula to solve for $I_L$ :

$I_L = rac{ ext{sqrt{3}} V_L ext{Cos}{ heta}}{P}$

Substituting the values:

$I_L = rac{ ext{sqrt{3}} imes 380 imes 0.8}{12000}$

Calculating this gives:

Approximately $22.79 \, A$ .

2.1 Noem die instrument wat gebruik word om elektriese energie te meet - NSC Electrical Technology Electronics - Question 2 - 2016 - Paper 1

Worked Solution & Example Answer:2.1 Noem die instrument wat gebruik word om elektriese energie te meet - NSC Electrical Technology Electronics - Question 2 - 2016 - Paper 1

2.4.1 Lynspanning

2.4.2 Fasespanning

2.5.1 Totale Spanning

2.5.2 Huidige Berekening

Join the NSC students using SimpleStudy...