On Monday, May 17, 2021 at 1:34:55 PM UTC-4, wrote:
On Mon, 17 May 2021 10:10:08 -0700 (PDT), "
wrote:

On Monday, May 17, 2021 at 12:10:47 PM UTC-4, wrote:

My spa controller is 4xxx CMOS but my pool controller is all relays
and switches with a cam timer on a 24 hour gear motor shaft.
Power surges will not hurt that although the 4xxx CMOS has lived
through 35 years of lightning strikes and power hits.

I may have posted this before, but this is a really good product and worth every cent.

https://www.amazon.com/Delta-LA302-R-120-240V-Lightning-Arrestor/dp/B006H3U4HS/ref=asc_df_B006H3U4HS/?tag=hyprod-20&linkCode=df0&hvadid=309804813335&hvpos=&hvnetw= g&hvrand=12948758990071981512&hvpone=&hvptwo=&hvqm t=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9010378&hv targid=pla-568919638940&psc=1

I have three on my house... one in one of the two, 200amp breaker boxes, one on the
well pump pressure switch, and one in the breaker box for my shop. I've never lost
anything to surges, at least that I know of. They do make several different products for
different applications.
I have several of those MOV protectors in the system along with some
point of use protectors.
It is important that you have all wires coming into your house
protected (cable, phone and power). All should be tied to the same
common grounding electrode system with the shortest wire possible.
You also need to be sure your grounding electrode system is good. A
ground rod or two isn't going to cut it.
I have a number of electrodes but the pool and concrete deck is
probably the best one. Everything is bonded.

Yep, it's not the potential (voltage) that kills things, it's the difference in potential. Years ago I went to
the fire lookout tower on top of Mt. Hough, Plumas County, California. The amount of grounding
was unbelievable. The four corners of the building had heavy ground wires that ran out across
the mountain top and had rods driven down through the solid rock. The idea is to keep everything at the
same difference in potential. The whole top of the mountain rose, then drained off. If the circuit runs off 5 volts,
but a strike causes the 5 volt buss to rise to 1005 volts while the ground buss rises to 1000 volts, then the
chips and circuits still see just a 5 volt difference. Nothing pops, everything is bonded together.
They said it gets struck several times a year, and they rarely lose anything. Probably gets
exciting for the lookout person, though.