My house is in a remote location, prone to lightning strikes nearby with the grid supply by overhead power lines. As a result I've suffered several failures of electronic devices in the house over the years including 2 Raspberry Pis, phone base station, central heating controller (twice), a RPi UPS, ethernet switch (twice), broadband router, the list goes on.

I've finally decided to try to do something about it as nature is not going to go away. I'm waiting on delivery of a SPD (data sheet attached, no real idea of its effectiveness but I'm willing to give it a go) as a first step to try and improve the situation but was wondering if anyone can suggest anything else I can also try as a belt and braces approach to the problem? Thanks

 

Could not find any review of the NMT2SPD3W/1 Type 2 Miniature SPD Kit. Let's see if anybody has used it here.

 

First you need to optimize your house grounding and ground bonding to that of a mini electrical substation. You need to shunt energy away from your devices by have a low impedance path to Earth for that energy. Where the grid supply main interrupt/meter is located you need a very good ground connection to Earth (physical Earth) with a whole house surge suppressor on the feedline directly connected to that good Earth connected ground (rods with a low impedance to Earth). Then you need every (very important) external communications (phone line, cable coax, alarms, sat dish, etc ...) line with a surge suppression/grounding block on the line grounded directly to that same good Earth ground point. There should be one bonded (several ground rods or point directly connected) ground for everything. What you want is to minimize the effects of Ground Potential Rise that will cause destructive currents to flow inside the house during a near strike. By having a single good ground point in the house for all devices, the rise and fall in GPR potential due to a near strike will keep all connected devices in the house at the same and equal potential.


https://electrical-engineering-portal.com/ground-potential-rise-in-your-home
https://esgrounding.com/ground-potential-rise

 

Thanks bidrohini, a lot to consider!

 

As an additional/alternative solution to that offered by nsaspook - I’d suggest the cheaper option of adding Metal Oxide Varistors (MOVs) across the mains at many locations within your property.

This ebay seller is selling 15 varistors (rated at 275V~) for £5.17. Varistors work by clamping the maximum peak voltage, effectively providing a short circuit between Live & Neutral to any voltage spikes on the mains – protecting electrical equipment from such damaging voltages.

I have fitted a varistor as an add-on component (connected Live to Neutral) within a number of direct plug-in night lights, which I have permanently plugged in to socket outlets around my home.

Of course you need to select varistors that are rated for your mains supply, should your mains supply be 120V~, then to give maximum protection the varistors should ideally be rated for a continuous voltage of no more than 150V~.

https://www.ebay.co.uk/itm/39344835...Kx60i6C9Bp4l49o0kRBLVgJHM=|tkp:Bk9SR-6MkszJYQ

 

It's not a matter of cheap or even a good alternative to minimizing systemic strike damage as you need both. Local MOV protection works with locally generated spikes but won't fix the root problem caused by ground potential rise across different ground potentials in a near strike.