Task:
It is necessary to make calculations and make a grounding project for the object.
Object: unit transformer substation (UTS) of class 10/0,4 kW. Length: 3,06 m; width 2,1 m; height: 4,5 m.
Soil resisitivity: 100 Ohm*m
Preferable variant: deep-laid modular grounding.
Download the layout of a unit transformr substation in PDF.
Download the layout of a unit transformr substation in DWG (AutoCAD).
Solution:
The activities were carried out in accordance with the EIC 7 th ed. Chapter 1.7
In accordance with the
In accordance with EIC 1.7.101
The set of measures to ensure the necessary requirements to the grounding device is represented by the following solutions:
- installation of two vertical electrodes 10.5 m long and one vertical electrode 9 m long, united by a horizontal electrode of stainless steel copper-plated corrosion-resistant tape with the cross-section of 30x4 mm. Depth of the tape burial 0.5 m;
- a horizontal ground electrode 3 meters long is being laid to the wall of the building (copper-bonded tape with the cross-section 30x4 mm).
Arrangement of elements of the grounding device is shown on Figure 1
Figure 1
Горизонтальный заземлитель – horizontal ground electrode
Вертикальный заземлитель - vertical ground electrode
Calculation of grounding device resistance:
Resistance of a horizontal electrode:
ρ - soil resistivity, Ohm* m;
b - horizontal electrode tape width, m;
Lгор - horizontal electrode length, m.
Resistance of a vertical electrode:
where ρэкв - equivalent soil resistivity, ohm · m; L - length of the vertical electrode, m; d - vertical electrode diameter, m; T- deepening - distance from the ground surface to the ground electrode, m;
where t - deepening of the electrode top, m
Impedance of the grounding device:
where n - number of kits; Kисп - utilization ratio;
The design resistance of the grounding device is 3.68 ohms.
The list of required materials:
| № | Fig | Product item | Product | Q-ty |
| 1 |  |
ZZ-000-030 | ZANDZ Universal grounding kit (30 meters) | 1 |
| 2 |  |
GL-11075-20 | GALMAR copper-bonded tape (30 * 4 mm / S 120 mm²; coil of 20 meters) | 1 |
| 3 | |
GL-11075-10 | GALMAR Copper-bonded tape (30 * 4 mm / S 120 mm²; coil of 10 meters) | 1 |
Appendix: the project is available in DWG and PDF formats
Files in the formats DWG and PDF are available for downloading only for authorized users.
Do you need to make the project on grounding and lightning protection? Order it by contacting the ZANDZ.ru Technical Center!
Any more questions on the calculation left? Ask them in the comments to this page!
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