What is EMP proof?

[MNwr786]

I would say the biggest risk to most people (that are not directly under the blast) is what the power lines will pick up and carry into your home via outlets. The power lines are antennas and there will be huge surges. One thing that is very effective at preventing that is to place NTC thermistors rated for just above line level after breakers and fuses. When a voltage spike comes in, they become short circuits and absorb the energy (usually destroying themselves) while the same pops the fuse or breaker disconnecting the device. We had lightning hit a power line and smoke a marine battery charger. One replacement thermistor and fuse and the charger was fine.

That EMP shield device you have there must do something similar??

 

[Proud Prepper]

It sends all excess voltage to ground @ close to a millionth of a second. It sets up its own electromagnetic field to do this. It will work against unlimited emp pulses, but only protects against one direct lightning hit.

 

[Proud Prepper]

I would say the biggest risk to most people (that are not directly under the blast) is what the power lines will pick up and carry into your home via outlets. The power lines are antennas and there will be huge surges. One thing that is very effective at preventing that is to place NTC thermistors rated for just above line level after breakers and fuses. When a voltage spike comes in, they become short circuits and absorb the energy (usually destroying themselves) while the same pops the fuse or breaker disconnecting the device. We had lightning hit a power line and smoke a marine battery charger. One replacement thermistor and fuse and the charger was fine.

That EMP shield device you have there must do something similar??

Yeah I think arc jumping will be a problem.

 

[MNwr786]

Yeah I think arc jumping will be a problem.

what about having a helium exploding spark gap to ground? The helium allows for greater arc distance than air at a given voltage, and if it is designed to get hot and vent the helium, the arc will extinguish itself insead of initiating a continuous high current short across your mains. Its a single event so the helium spark gap will shunt the bulk of it and the thermistor or TSD can handle whats left.

 

[DrHenley]

I will not comment directly as this is outside my wheelhouse. But there is a report that was prepared for Oak Ridge on the subject which is a long read and very technical, but is probably THE definitive source on the subject of the E1 component of a HEMP.
I haven't had time to wade through the whole thing yet.

http://large.stanford.edu/courses/2019/ph241/rogers1/docs/meta-r-320.pdf
The Early-Time (E1) High-Altitude
Electromagnetic Pulse (HEMP) and
Its Impact on the U.S. Power Grid
Edward Savage
James Gilbert
William Radasky
Metatech Corporation
358 S. Fairview Ave., Suite E
Goleta, CA 93117
January 2010
Prepared for
Oak Ridge National Laboratory

Below is just the foreword of the paper. You can download the pdf of the entire report from the link above.

FOREWORD
This report describes the threat of the early-time (E1) high-altitude electromagnetic pulse (HEMP) produced by nuclear detonations above an altitude of ~30 km. The report describes the mechanisms that create the E1 HEMP, the evidence for oncern about this threat, and how it can impact the U.S. power grid. As the late-time (E3) part of the HEMP is considerably different in its frequency content and how it affects the power grid, this aspect will be discussed in another report.

This report is organized to provide an introduction to the report in Section 1, followed by an overview of E1 HEMP in Section 2. Section 3 then provides a brief history of E1 HEMP experience. Section 4 discusses in some detail how the E1 HEMP is generated for those who have more interest in the physics of the problem. Section 5 presents details concerning the coupling of these fields to extended lines, while Section 6 describes vulnerabilities of electronics to this threat. In Section 7 there is a detailed discussion of the main concerns of E1 HEMP on the U.S. power grid, and this section is crucial to set the stage to describe and recommend protection approaches and methods in the future. Section 8 follows with a brief discussion of potential impacts of large-scale power outages on society. Section 9 provides a bibliography highlighting some of the most important papers dealing with the E1 threat, standards to deal with the impacts of the threat, and recent publications produced for the EMP Commission and other groups related to the vulnerability of different aspects of the U.S. power system to electromagnetic threats. Finally, an appendix discusses some common E1 HEMP myths.

 

[MNwr786]

Im to page 48, good stuff there. Thanks fr sharing! They are going into great detail on what I was trying to say.