# CALCULATION EXAMPLE OF WORKING GROUNDING FOR AN ELECTRIC LABORATORY

In what organizations for checking electrical installations, quality control of electrical safety of facilities, electrical safety and the functioning of electrical equipment should everything be at the highest level? One of them is an electric laboratory!

The ZANDZ Technical Center received a request to calculate the working grounding for the electric laboratory. Further we will consider what our engineers have offered!

Initial data:

• specific resistance of the soil used for calculations – 100 Ohm * m;
• the available area for the installation of the grounding device is 30x30 m.

It is necessary to calculate the working grounding device with a resistance of not more than 0.5 ohms.

The set of measures to provide the required lightning protection is offered by the following solutions:

- Installation of a grounding device, consisting of a grounding mesh with a pitch of 3x3 m using a copper-bonded tape with the cross section of 30x4 mm, and vertical electrodes 3 m long, in knots (106 pcs.). The burial depth is 0.5 – 0.7 meters.

Grounding device resistance calculation:

The design resistance of the grounding device is 0,49 Ohm, which is less than the required value of 0,5 ohms.

Конструкция заземляющего устройства показана на рис.1

Figure 1 - Location of equipment.

Вертикальный электрод – vertical electrode
Полоса омедненная – copper-bonded tape

The list of required material is given in Table 1.

Table 1 - Materials requirement list.

 № Fig. Product item Name Quantity, pcs. 1. ZZ-001-065 ZANDZ Copper-bonded threaded grounding rod (D14; 1.5 m) 212 2. ZZ-002-061 ZANDZ Threaded coupler 107 3. ZZ-003-061 ZANDZ Starting tip 106 4. ZZ-004-060 ZANDZ Driving head for a jackhammer 43 5. ZZ-006-000 ZANDZ Conductive grease 11 6. ZZ-008-000 ZANDZ Header for a jackhammer (SDS max) 2 7. ZZ-005-064 ZANDZ Clamp for connecting conductor (up to 40 mm) 118 8. ZZ-007-030 ZANDZ Waterproof tape 29 9. GL-11075-50 GALMAR Copper-bonded tape (30 * 4 mm / S 120 mm²; coil of 50 meters) 12

Do you have questions or do you need to calculate the working grounding for the electric laboratory? Send your request to info@zandz.ru.