A CCTV system is an essential part of providing security, safety of material assets and control over the operation of the railroad station personnel. To ensure proper operation of the equipment, a reliable grounding system is required. The ZANDZ Technical Center received a request to calculate the grounding for the CCTV system for railroad stations. Let us continue with more detailed review of our offered solution.
Calculation of Grounding of a CCTV System for Railroad Stations
Facility: a CCTV system for railroad stations
Task: to perform calculations for grounding of the CCTV system for railroad stations
Solutions to meet the requirements to the grounding system for the CCTV system for railroad stations:
- Grounding is made in accordance with the 7th edition of the Electrical Installations Code.
- Grounding arrangement (GA) is necessary to do with a resistance of not exceeding 4 ohms.
- The soil resistivity accepted for calculations is 80 Ohm * m.
- Stairs and handrails are connected by using clamp GL-11514.
- Three vertical steel copper-coated electrodes 9 m long are used as grounding electrodes. The copper-plated steel strip with a cross-section of 30 x 4 mm, combining all vertical electrodes, is used as a horizontal ground electrode. The distance to the facility foundation is at least 1 m. Strip deepening is 0.5 to 0.7 m.
- Connection to the grounding arrangement is made through clamps ZZ-005-064.
Ground terminal resistance calculation:
Rверт. - Rver
Rгор1 - Rhor1
Rзу - Rga
Ом - Ohm
The design resistance of the grounding arrangement is 3,5 ohms.
Figure 1 shows hardware layout.
Table 1 includes the list of required hardware and materials.
Figure 1. Hardware layout for the grounding of the CCTV system for railroad stations.
Вертикальный электрод длиной 9 м - Vertical electrode of 9 m long
Полоса 30х4 мм - Strip 30 x 4 mm
Table 1. List of material requirements.
Do you have any questions about lightning protection of the CCTV system or other facilities? Please, contact the ZANDZ Technical Center!