Sometimes the shocking effect of an earthquake has greater consequences beyond physical damage. In addition to visible damages such as cracking walls or breaking windows, fires, explosions and electric shocks that occur as a result of electrical panels falling over, cable systems breaking or short circuits can be one of the main causes of loss of life. Therefore, designing and protecting electrical systems to be resistant to earthquakes becomes not only a technical choice but a vital necessity.
Fixing and Safety of Electrical Panels
Since electrical panels are the energy distribution center of the building, it is important that they are securely fixed against shocks. The placement of the panels should be planned to minimize the risks of tipping and vibration. In addition, a panel equipped with residual current relays, fuses and automatic breakers plays a critical role in preventing possible short circuits or electrical leaks from turning into a fire. In this direction;
► For the assembly of panels, panels complying with TS EN 61439-1 standard should be preferred. This standard determines the mechanical durability and safety requirements of panels.
► Panels must be connected directly to reinforced concrete or steel carrier systems using special anchor screws and steel fasteners that are resistant to seismic loads.
► Circuit breakers (MCCB), residual current relays (RCD) and fuses used in the panel must comply with IEC 60947-2 and IEC 61008 standards, and vibration and shock resistant types must be selected.
Flexible Cabling and Movable Connections
Buildings flex and slide during earthquakes. Rigid and fixed cabling systems are vulnerable to these structural movements and may break or cause a short circuit. Therefore, in flexible cable systems, XLPE (Cross-linked Polyethylene) insulated, low smoke, low toxic gas emitting (LSZH – Low Smoke Zero Halogen) cables should be preferred to increase earthquake resistance. Especially wall transitions and device connection points should be supported with spiral protective cases.
Backup Power Supplies (UPS and Generators)
In cases where the main energy source is cut off, uninterruptible power supplies (UPS) and automatically activated generator systems are required to ensure that the vital systems of the building continue to operate. Generators should be integrated with automatic transfer switches (ATS) to ensure fast and uninterrupted power transfer in case of grid outages. These systems ensure the continuity of many critical infrastructures, from life support devices to fire detection systems in hospitals. It is of primary importance to keep backup power systems in working order through periodic tests.
Uninterruptible Power Supply (UPS)
Effective Grounding and Protection Systems
Electrical leaks that may occur after an earthquake pose a serious danger in terms of both life safety and fire risk. Considering that grounding resistance may increase after an earthquake, grounding electrodes should be designed as deeper or multi-electrode systems. An effective grounding system should be established in buildings and all connections should be checked after the earthquake. Protection elements such as residual current relays (RCD) play a role in preventing shocks caused by electrical devices.
Fire Detection and Automatic Extinguishing Systems
Earthquakes cause short circuits in electrical systems, increasing the risk of fire. For this reason, fire detection systems supported by smoke, heat and flame sensors and automatic gas extinguishing systems (such as FM-200, NOVEC 1230) should be used. Especially electrical rooms, generator rooms and server rooms should be covered with fire-resistant materials and integrated with extinguishing systems, and smoke and heat detectors should be positioned at critical points.
Physical Fixation of Electrical Equipment
Large electrical equipment such as transformers, generators, UPS devices and battery groups should be fixed to the ground to prevent them from falling over during an earthquake, seismic calculations should be made meticulously and appropriate anchoring systems should be used. Anchorage systems should be secured with clamps and anti-vibration equipment. In this way, the equipment is protected and the risk of injury to users is reduced.
Some Anchor Types
Automatic Shutdown Systems and Seismic Sensors
The biggest threat that electrical systems can pose during an earthquake is that they continue to operate uncontrolled. To eliminate this risk, automatic closure systems integrated with seismic sensors should be used. These systems automatically cut off risky circuits when an earthquake is detected, greatly reducing the risk of fire, explosion and electric shock.
Maintenance, Inspection and Training
No system can remain secure without regular maintenance and inspection. Electrical systems should be checked periodically, leak tests should be performed and connection points should be reviewed. However, building users’ and technical personnel’s knowledge of how to act in possible emergency scenarios plays a critical role in reducing the effects of the disaster. Drills, training programs and written procedures form the basis of this process.
Visible Precautions Should Be Taken Against Invisible Dangers
Earthquakes are inevitable; However, its effects can be largely controlled with correct engineering practices. Electrical systems are among the most life-threatening secondary disasters after structural damage. Therefore, electrical earthquake protection is not a luxury but a vital necessity.
Just keeping the building standing is not enough for earthquake safety; The systems within it must also continue to operate safely. It is essential that the electrical infrastructure, which is invisible to the naked eye but carries vital risks, is designed by taking earthquake scenarios into consideration, is regularly inspected and supported with training.