FYI, EMP and CME protection for your QTH


Fred Dittrich
 

Hi

Check this out: https://www.youtube.com/watch?v=bPSTFe1dBAg 3-steps to Whole-House EMP Protection

73

Fred AE0FD


paul watt
 

Great info!! Thanks Fred
73
Paul KE0IKG 

On Mar 18, 2023 19:26, Fred Dittrich <fdittric@...> wrote:

Hi

Check this out:
https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DbPSTFe1dBAg&data=05%7C01%7C%7Cb5c8b1ea510a46bc898a08db281091d7%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C638147823850749873%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=NxTz%2B3IqB30TwMYk6EVLOFisKM3gaFjSInObl7LuBYw%3D&reserved=0    3-steps to Whole-House
EMP Protection

73

Fred AE0FD








Fred Dittrich
 

Paul

After having slept on this I have a question. How is this going to trip your 200A breaker through a double 20A or 30A breaker?????  I understand the carefully selected and adjusted ferrite beads to avoid saturation. Would one of our retired EE's please comment?

73

Fred AE0FD


At 09:30 PM 3/18/2023, you wrote:


paul watt
 

Interesting thought Fred.  Without the specialized knowledge of being an EE or electrician I can only assume the pulse itself would trigger the main breaker and the spd would pickup anything that may have surged thru.  Again I am no expert. I am just making a logical assumption based on how this thing wires into the box.  I will send this query onto my step-dad who is an EE and see what he says. Stay tuned (bad ham joke 😸) 
73
Paul KE0IKG 

On Mar 19, 2023 06:18, Fred Dittrich <fdittric@...> wrote:
Paul

After having slept on this I have a question. How is this going to trip your 200A breaker through a double 20A or 30A breaker?????  I understand the carefully selected and adjusted ferrite beads to avoid saturation. Would one of our retired EE's please comment?

73

Fred AE0FD


At 09:30 PM 3/18/2023, you wrote:
Great info!! Thanks Fred
73
Paul KE0IKG

On Mar 18, 2023 19:26, Fred Dittrich <fdittric@...> wrote:

Hi

Check this out:
https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DbPSTFe1dBAg&data=05%7C01%7C%7Cb5c8b1ea510a46bc898a08db281091d7%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C638147823850749873%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=NxTz%2B3IqB30TwMYk6EVLOFisKM3gaFjSInObl7LuBYw%3D&reserved=0   3-steps to Whole-House
EMP Protection

73

Fred AE0FD








Gary Vaught - W9TIG
 

It's been a lot of years since I worked as an electrician and technology may have changed, but my understanding of breakers has been that they're essentially thermal devices that are designed to open, or trip, when to much current is drawn, or pushed, through them and hearing up the trip mechanism. As fast as that happens, it still takes time to occur. That few milliseconds is where the threat comes into play. I need to watch the whole video but my concern is on his affinity for 10ga wire. If the surge had the potential to be over 300 volts and requires a 100kA sink, I don't see the 10ga wire laying much longer than 12 or 14 ga.

But I could be totally wrong about all of it and will happily defer to correction from Earnest, Chris, or anyone with better info.

--
73
W9TIG

Gary Vaught


Brad Wilmot
 

You're right. Most breakers are thermal, with some larger ones being both thermal and magnetic. While a large surge/spike can trip a breaker, it's usually because something downstream shorted out, not by the surge itself. The pulse width is so short (microseconds), a breaker simply doesn't have time to react (even an overloaded breaker will take seconds to minutes to trip). Same principal with small conductors to the SPD. Yes, they're small, but the spike width is so short that the wire won't even get warm while shunting a spike to ground.

Brad Wilmot
Building Systems Engineer
University Place Apartments
W0VHA

-----Original Message-----
From: main@CMRA.groups.io <main@CMRA.groups.io> On Behalf Of Gary Vaught - W9TIG
Sent: Monday, March 20, 2023 9:29 AM
To: main@CMRA.groups.io
Subject: Re: [CMRA] FYI, EMP and CME protection for your QTH

It's been a lot of years since I worked as an electrician and technology may have changed, but my understanding of breakers has been that they're essentially thermal devices that are designed to open, or trip, when to much current is drawn, or pushed, through them and hearing up the trip mechanism. As fast as that happens, it still takes time to occur. That few milliseconds is where the threat comes into play. I need to watch the whole video but my concern is on his affinity for 10ga wire. If the surge had the potential to be over 300 volts and requires a 100kA sink, I don't see the 10ga wire laying much longer than 12 or 14 ga.

But I could be totally wrong about all of it and will happily defer to correction from Earnest, Chris, or anyone with better info.

--
73
W9TIG

Gary Vaught