EMP Shield Response Time: Why Speed Matters

When it comes to surge protection, speed matters more than most people realize. The E1 phase of an electromagnetic pulse has an extremely fast rise time, typically reaching peak intensity in approximately five nanoseconds. If a surge protector cannot react quickly enough during that initial rise, more damaging energy can reach connected equipment before diversion even begins. Response time is one of the most critical performance metrics for any surge protective device, though it works alongside other factors including maximum discharge current, surge rating, and voltage protection levels to determine how well a device actually performs under real world conditions. EMP Shield‘s response time is one of many areas where it sets itself apart.

Most standard Type 2 surge protective devices on the market today, including name brand units commonly found at big box stores, have response times that fall between one and twenty-five nanoseconds. That range is well documented in IEEE standards, semiconductor manufacturer data sheets, and testing organization benchmarks for MOV based surge protective devices. While one nanosecond sounds fast in everyday terms, it is still long enough for a meaningful amount of transient energy to pass through before protective components fully engage, particularly during the steep rise of an E1 pulse.

How fast a device reacts comes down largely to how its diversion path is designed. Excess voltage needs to reach ground before it reaches your equipment, and the shorter and more direct that path is, the faster it gets there. Devices with longer internal leads introduce impedance into that path, which slows the reaction and allows voltage spikes to push further into the system before they can be stopped. According to Eaton Corporation’s surge protection application guides, lead length alone can add approximately one nanosecond of delay and 150 to 200 volts of let-through voltage per foot of wire, which is why installation quality and internal design both play a significant role in real world performance.

EMP Shield begins reacting in less than one nanosecond, fast enough to start diverting a surge during the initial rise of the E1 phase itself. That speed is the result of our patented SightSpeed technology, which enables EMP Shield to monitor and protect an entire electrical system rather than just the location where the device is installed. The specifics of what makes that possible are proprietary, but the performance is independently verified through third party testing at Keystone Compliance, a Department of Defense certified testing facility. Those results are publicly available on our website.

What that speed means in practical terms is that EMP Shield is designed to begin shunting excess energy from the system before it can reach sensitive electronics. By reducing the energy that reaches connected equipment, the heat and electrical stress that destroy circuit boards is minimized before it can build to damaging levels. That holds true whether the source is a standard power surge, a lightning strike, or a full scale EMP event.

Speed is what separates real protection from the illusion of it. If you have questions about how EMP Shield compares to what you currently have installed or what the right model is for your system, give us a call. We are happy to walk you through it.