Busbar calculations – Busbar is a copper or aluminum conductor or conveyor bar that collects power from one or a single electrical circuit and supplies or distributes power to one or one electrical circuit.

Table of Contents

## Calculations of residence

Basar calculation/selection is done in two ways

- Directly based on the value of the current and
- Based on the rating of the transformer.

### (LT) Busbar calculations on low voltage lines

Basar calculations are mainly calculated based on the rating of the cable (ampere). Notice the image below. Does the figure show the low voltage side busbar?

The first method is to know directly the current value or the size of the cable:

The size of the cable in the low voltage line is given in the figure above:

( 4 * 4 * ( 1*500 ) rm )Which means( 1 * 500 ) rm Being = 900 A.

The circuit breaker value is given in figure ACB = 3200 A.

For this circuit breaker ( 1 * 500 ) rm = 900 A Cable selection has been made. Since 4 o’clock ( 1 * 500 )rm The size of the cable has been taken,

4 * ( 1*500 ) rm Where ( 1*500 )rm = 900 A

Total Cable ( 4 ) * Cable Size ( 900 )rm

4 * 900 = 3600 A

We know that for the calculation/selection of the busbar the rating of the cable is equal to (ampere) or the busbar is selected at the above rating. 3600 Ampere is at the top rating 4000 This is the ampere busbar 4000Ampere has to do busbar calculation and selection.

#### The second method is to know the rating of the transformer:

A transformer rating is given in the figure. Line current is first extracted from the transformer rating and the safety factor is calculated by multiplying the safety factor by 1.25.

Transformer Rating = 2000 KVA

Line Current = 2887 A

Safety Factor, (S.F) = 1.25

= 2887 * 1.25

= 3608 A

3608 Ampere’s top rating is Busbar 4000 Ampere and this 4000 Ampere has to do busbar calculations.

### Busbar Size Selection

The size of the Width and Height of any busbar is fixed, but the size of the length is not specified. For this, it is important to know the size of the Width and Height of the busbar. Below is a chart of Busid’s Width and Height.

### A chart of the size of the busbar available in the market

Width * Height (W*H) | (W*H) sqmm | (W*H) sqmm |

25*05 | 60*05 | 100*08 |

30*05 | 60*08 | 100*10 |

30*08 | 60*10 | 100*12 |

35*05 | 70*05 | 110*08 |

35*08 | 70*08 | 110*10 |

40*05 | 70*10 | 110*12 |

40*08 | 70*12 | 120*08 |

40*10 | 80*05 | 120*10 |

50*05 | 80*08 | 120*12 |

50*08 | 80*10 | |

50*10 | 80*12 |

Basar calculations are usually done using formulas.

Source:

- sqr mm = 2 Amp Current

1 Square m m = 2 amperes current

1 mm Width * 1 mm Height = 2 Amp Current

Just look at the image of the busbar, I do not see any part of the busbar to calculate the Width * Height.

The figure shows Width and Height side by side and this Width * Height is calculated by calculating the bus.

#### 4000 Busbar calculations for umpires

We are the two methods above 4000 I got an ampere current. 4000 Ampere must calculate the busbar.

We know,

1 sqr mm = 2 Amp Current

So,

2 Amp Current = 1 sqr mm BusBar

4000 amp Current = 4000/2

= 2000 Sqr mm BusBar

2000=Square Mr. Busbar

Then 4000 For the ampere current 2000 Mr. Square’s residence is required. Based on the chart above, I will select the busbar.

From the busbar chart,

If

Width = 100 mm AndHeight = 10 mm Is taken and multiplied

So,

Width * Height

= 100*10

= 1000 sqmm

The selection of the busbar is done by adding one or more busbars together Basar calculations are mainly calculated based on the rating of the cable (ampere). Notice the image below. Does the figure show the low voltage side busbar? cable selection. Since we 1000 Square mi busbar selection then we have 2000 Square m busbar will be required 1000 Square m is two dwellings that hold or join together 200 I can make the square meter busbar selection. Note the image is connected to the same size one-to-one bus.

## Busbar Size Calculation

The size of the busbar is selected based on the size of the panel box. The size of the panel box will be the same size as the bus. However, when the busbar is inserted inside the panel box, it is cut slightly and inserted inside.

## Basar weight calculation

Length of the bus 30 Fit(9144 mm), And height 10 Mm and width 100 mm [(100*100)mm^2]

We know,

Size = Length * Height * Width

= 9144 * 10 * 100

= 9144000 mm^{3}

= 9144000/10^{9}

=9.0144 * 10^{-3 }m^{3} (Taken in meters)

Weight:

Mass = row * size

= 8960 kg/m^{3} * 9.0144*10^{-3}

= 81.93 kg

## Pricing for a home

If the size and weight of the busbar are known, then pricing is not difficult. First, you need to look at the size of the busbar that you want to buy. When buying a bus, you will have to calculate the difficulty. If the weight is closer or equal to the size, then the settling is OK, the adhesive is less than (copper) and if the weight is less or too much according to the size, then the residue is not OK, the amount of adulteration mixture is very high. If the size and weight are right, you can calculate the cost of the copper by the price per copper.

Cigarettes per pound of copper 800 taka

So,

81.03 kg * 800 taka

=65544 taka

### (HT) busbar calculation on the high voltage side

On the high voltage side, the bus selection and calculation are exactly like the low voltage side. The safety factor has to be multiplied only with the line current.

Line current in the figure 105 An ampere is given. With it 10You have to multiply the busbar selection and calculation.

So,

ine current = 105 * 10

= 1050 A

this 1050 Ampere Current will have to do busbar calculation. The busbar calculation formula applies:

1 sqr mm = 2 Amp Current

2 Amp Current = 1 sqr mm BusBar

1050 amp Current = 1050/2

= 525 sq mm BusBar

= 600 Square MM Busbar

1050 A for this 600 sqmm Size size is required. From the Size Selection Chart Width * Height = 60 * 10 = 600A The size of the busbar was selected.

There is no problem if the size is a bit higher but it would not be okay to take extra. Then the rest of the work is similar to the bus voltage calculation on the low voltage side. Here may be a question: Why is the low voltage busbar selected on the high voltage side? Because the current is low on the high voltage line and the current is selected based on the current.

The size and weight of the HT side busbars are the same as the LT side. If you have any questions about your account or your text, please comment.

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