EMP: Electromagnetic Pulse Protection

Critical electronic systems & Protection from EMP

What is EMP

An Electromagnetic Pulse (EMP) is a burst of electromagnetic radiation, creating energy that can easily damage and destroy electronics. EMPs are rapid, invisible, and often unpredictable bursts of energy that is produced by a nuclear detonation, powerful natural solar events or EMP bombs. When exposed to EMP, permanent damages occur in electronic components, systems, and networks.

Critical Electronic installations such as DATACENTER, SCADA systems of the electrical grid, electronics in critical infrastructure such as railways face existential threat from various EMP including manmade EMP, and natural EMP from a solar superstorm. Manmade EMP include high-altitude EMP (HEMP), Source Region EMP (SREMP) and Intentional Electromagnetic Interference EMP (IEMI).

HEMP results from a nuclear detonation, typically occurring few 10’s of KMs above the Earth’s surface. HEMP could cause failure in electronics, widespread power outages, communication disruptions and possible damage to the electricity grid. SREMP is a burst of energy like HEMP but differs in that it is created when a nuclear weapon detonates at lower altitudes on or near the ground, as it would likely to be a case of an intentional nuclear attack. IEMI are created by Radio Frequency Weapons designed to produce sufficient electromagnetic energy to burn out or disrupt electronic components, systems and networks.

EMP in its various forms can cause widespread disruption and long-lasting damage to critical infrastructures such as the electronic devices and networks in communication systems, information technology equipment, and SCADA modules. Realising the danger behind EMP, developed nations already started implementing HEMP protective measures for critical electronic system installations such as DATACENTER.

Fig: Frequency spectrum various EMP

 

Why Indian electrical installation practices need improvement to protect from EMP

The electrical systems in the facility should follow the rules and code of practices as a fundamental requirement for safety (eg. NFPA 70 in USA or BS7671 in UK). All other requirements such as the performance-based methodology for the DATACENTER (called as Tier 1 to tier 4) are followed in addition to the requirements of the rules and code of practices. Confusions and misinterpretation of the rules and codes often lead to violation of the basic safety requirements. As a result, the additional reliability measures (e.g. Tiered classification) could be unreliable.

Electrical safety subjects those are mainly related to earthing such as fault loop, touch voltage reductions, functional earthing and shielding against EMP are at a premature state in India, even in critical installations such as DATACENTER, SCADA systems, Railway signaling. It is evident from the practice of connecting each part of electrical installation to two earth electrodes, without even understanding the basics of earthing. Electrical installations with huge no’s of earth pits in soil all around the building connected to various parts of one electrical installation are neither safe nor reliable. Due to the nonstandard installation practices followed in India, protection of electronics from conducted and radiated effects of EMP is difficult.

Figure: Example of radiated HPEM at high frequencies

(The van in the center of the picture contains the HPEM source)

What is necessary for the protection of critical electronic installations??

The external environments and the protection concepts result in internal environment levels which are appropriate for equipment or subsystems that are placed within these protection zones. The concept applies in dividing the environment into protective zones and implementing appropriate protective measure in respective zone.

Infrastructures built for critical application such as DATACENTER shall serve not only for few decades but ensure the future technical demands of electronic networks. For new and upcoming DATACENTER buildings, the modern protective measures can be implemented without much additional cost, if planned well in advance. Implementing the safety measures during the initial stage of construction, add much value to the building in future, often unmeasurable value.

Challenges

However, the great challenge is in planning and implementation of certain aspects during the civil construction of the building and a major change in the mindset of engineers in removing the wrong and dangerous practices followed in basic safety measure which are hinderances in electrical safety and reliability.

WEBINAR on EMP protection

Videos of the webinar

1. Introduction

2. Main Presentation by Dr. D C Pande

3. Presentation by S. Gopa Kumar: Why Indian installations need improvement

4. Q&A

The webinar was attended by more than 200 engineers