EMC for Mission-Critical Applications

EMC for mission-critical applications

Mission-critical applications enable some of the most important business operations in the world. They help hospitals stay running and allow nuclear power plants to stay safe and deliver utilities to their destinations. A mission-critical application is a system that must be continuously operational for a business to be successful. The term generally applies to businesses for which disruptions would have significant adverse effects on safety or health, like medical or military facilities.

These applications depend on reliable electrical signals to support the systems, which is why electromagnetic compatibility (EMC) becomes a vital part of the equation. Filtering out unwanted signals — electromagnetic interference (EMI) — is an essential component of mission-critical applications. Astrodyne TDI builds high-quality EMI/EMC filters for the most stringent of applications, including mission-critical requirements. We'll go over the role of EMC in these settings and how you can support mission-critical applications with reliable power supplies.

What Makes Mission-Critical Applications so Important?

Perhaps the best way to illustrate the importance of mission-critical applications is to compare them to business-critical applications. Both refer to applications that, if they were to fail, would cause significant disruptions to the business. In the case of system failure, the business would not be able to continue operations. Business-critical applications, however, are generally limited to economic effects, like lost customers or reputational damage. A failure might hinder productivity or affect the user experience, but the impact is limited.

Mission-critical applications, on the other hand, have wider-reaching, more serious effects like risks to public safety. A hospital that loses power to life-saving medical devices faces a clear and present danger, but an accounting firm that loses power for a few hours isn't facing the same level of risk. The company loses money during the experience and possibly some reputational damage, but typically, no disaster occurs.

An organization with a mission-critical application failure cannot conduct operations at a basic level, which could result in significant adverse effects on society and the business. In both cases, the company itself will likely see damaging effects on its reputation and revenue. Downtime can result in sizable costs, especially when the risks of mission-critical applications are added.

types of mission-critical applications

Types of Mission-Critical Applications

Some examples of mission-critical applications include:

  • Electrical power grid systems: If an electrical power grid fails, millions can go without power. The consequences can range in severity with potentially disastrous threats to safety, like dangerously low temperatures during winter storms.
  • Railway operating and control systems: Railway systems are complex, and operating systems must work as intended to avoid collisions and derailments.
  • Medical devices: Power failures for medical devices pose significant risks to the users with the potential to cause health complications and affect life-saving support systems. 
  • Nuclear reactor safety systems: These systems have the vital role of keeping nuclear chain reactions in check. From electricity generation to medical and research uses, nuclear reactors are used in a range of settings near populated areas. Failed nuclear reactor systems have the potential to create disastrous consequences.
  • First responder systems: Communication systems link up first responders to ensure appropriate dispatching and immediate engagement when disaster strikes. If EMI affects these systems, response times can be significantly limited, hence the need for dependability.

Combatting Mission-Critical Application Downtime With EMC Filters

Military, medical, scientific and commercial endeavors all depend on engineers developing systems that are electromagnetically compatible. The EMC term means that each system that may develop noise in the electromagnetic spectrum, be it conducted or radiated, produces amounts that are at levels that can be tolerated by other elements of the system. This definition suggests that the victim modules have a certain level of immunity to noise being passed to them by noise sources.

Before discussing EMC, it helps to revisit how EMI works. Electromagnetic interference is the noise that comes from external electromagnetic waves. Every electronic device creates them, and they come in two variations. Conducted EMI moves through power connections, parasitic impedances, and ground connections, while radiated EMI occurs with no physical contact. Device designers typically implement mitigation features to reduce the amount of EMI a device emits and how much enters the device itself.

To meet EMC demands, designers can use a variety of noise-reducing technologies. One of the most common and most useful strategies is to add an EMC filter. These filters reject noise that the device doesn't need to operate, effectively reducing the amount of noise that enters the system. They can come in a variety of styles, with potential variations in elements like:

  • Frequency: An EMC filter is almost always a low-pass filter, meaning it cuts off signals above a specific frequency threshold. This is a common choice because most noise from radiation is at high frequencies. Other options, including high-pass or bandpass designs, can reject other frequencies if needed. Choosing the cutoff point can be challenging, but it ensures the necessary signals get through without much noise.
  • Placement: While an EMC filter can be placed at various levels throughout the circuitry, the best placement is usually between the equipment and its external environment. This location can keep EMI from ever entering the equipment, where it is more challenging to mitigate and can add design complexity, such as weight and volume.
  • Signal rejection method: An EMI filter either rejects or absorbs the rejected frequencies. If reflected, noise is typically directed toward a low-impedance path back to the ground. Both types of designs can range in complexity.

Without EMC technology, electronic devices might experience power or signal interruptions, which can lead to malfunctions or complete failure. In most mission-critical applications, even minor malfunctions can have severe impacts, so creating reliable systems via high-quality EMC solutions is essential.

Two classic examples of a failure to achieve EMC that are cited in military Naval and EMC circles are the 1967 aircraft carrier USS Forestal fire and the sinking of HMS Sheffield in the Falklands War in 1982. Each of these events has origins in high-energy RF signal releases into an environment loaded with hazards sensitive to this energy. In the case of the USS Forrestal, interference with a missile loaded on an aircraft located on the flight deck resulted in the missile’s inadvertent firing and the disastrous consequences that arose from it. In the case of HMS Sheffield, the crew was forced to turn off the ship’s surveillance radar to establish a communications satellite link, because the surveillance radar and Satcom systems were not able to operate simultaneously. This left the ship “blind” to an inbound enemy missile that was not detected in time for the crew to defend the ship.

RF emanations can also negatively impact mission-critical applications. These are inadvertent releases of RF energy that can be intercepted and used to reconstitute signals and messages with sensitive content. If the enemy or outside agency can eavesdrop and collect this data, they may secure the initiative. 

Find EMC filters for mission-critical applications from Astrodyne TDI

Find EMC Filters for Mission-Critical Applications From Astrodyne TDI

When mission-critical applications are involved, dependability is of utmost importance. High-quality EMC filters can deliver the noise reduction needed to meet tight specifications and help businesses continue to provide essential services. Astrodyne TDI has put decades of experience to work to develop top-tier EMI/EMC filters for mission-critical applications. Our industry partners include those in the aerospace, industrial, medical, military, and semiconductor manufacturing sectors.

With a variety of off-the-shelf solutions and custom capabilities, we can help you meet strict EMC demands for everything from medical devices to missile and radar systems. We run facilities that are ISO 9001 and ISO 13485 certified and meet or exceed worldwide safety and EMI specifications. The Astrodyne TDI range includes filters designed for reducing RF emanations along power and communication lines. HEMP filters are also included in the line, although these are very specialize filters that only find active usage in high-altitude electromagnetic pulse scenarios i.e. in nuclear wars. Learn more about our work or request a quote by reaching out to us today.