nice looking firewood Frits. Plus your equipment always looks good.
after having my hvac system fried by a power surge/lightning/something,
which also belatedly I believe took out my dishwasher, for the first time, I made sure the
dishwasher was a plug in and plugged that into a heavy duty Tripplite surge protector.
our appliances are getting more delicate. They are now online with us.
more circuitry to get zapped and you can bet they don't spend the one dollar or less to build
in a nice MOV into their own product. In a user friendly/accessible spot with a plug in replacement.
no such thing, most of what we buy runs pretty bare.
MOVs are your friend
one Christmas I built Heathkit surge protector strips for my family.
now they are really cheap and should be used everywhere if you don't have a whole house unit.
and even then, on gear like Scott's, I'd have several layers of protection.
I am not sure higher surge ratings are the ultimate test of quality.
other than filtration, what else makes a better surge protector?
.42 rain and a dark rainy morning
At one point, I was responsible for hardening some sensitive equipment against localized EMP events on a poorly functioning grid. I think more modern equipment is both better and worse than it was many moons ago, but anything with a circuit is vulnerable.
I don't know if this is the right way to think of it, but I think of surge/EMI protection as being layers.
A whole house protector typically can absorb more energy (current x time) than a strip surge protector. Typically, these only divert surges to ground. (No EMI filtering)
A surge strip should I think be close to your equipment, and often has lower clamping voltages for limiting the energy going into your equipment. Better ones often come with EMI filtering to provide cleaner power to the protected equipment.
Wiring from the main service panel to an outlet can act like an antenna to funnel a nearby EMP event into wiring as a voltage spike, so having multiple points of surge protection distributed around a house helps limit the spike/surge. Wiring also can act as an attenuator of spikes (flashover, and inductance effects), so there's theory of what happens in the testing lab, and then there is how your site is wired, and what its risk is.
(
Discussion of kA vs Joules here)
There are both MOV based systems and gas tube (air gap) systems, and they have their uses.
I tend to go as large as possible on the sizes, as they are all small potatoes, compared to what can come down the line.
Then there are the gems that
@WinterDeere brought up;
A few comments on surge protectors and lightning arresters. There is no product available on a consumer budget, that is going to protect your equipment (esp. receivers!) from a lightning strike on your antenna. Similar with surge arresters, any direct hit on your transformer is likely going to blow out all connected equipment, the amount of energy imparted onto the circuit is just too great to be handled by the surge suppressor in every case.
So when shopping this equipment, look at the warranty or equipment guarantee, and see if you can find information online about how good or difficult the company is about supporing this guarantee.
I did some work for an industrial surge suppressor and UPS company in the 1990's, who was making some small ventures into the consumer market, and they were always the first to admit they couldn't really stop direct hits. Their claims and equipment gaurantee numbers were based on a business case and not a technical case. In other words, they fully realize they can't protect all equipment from direct hits, but they sell enough UPS's and surge supressors to be able to afford to replace the occasional $3k computer or Ham receiver under the equipment gaurantee, when disaster does strike.
What you're buying, in these products, is something that will handle transients resulting from more distant strikes (e.g. power line a half mile away from your house), coupled with an insurance policy on your equipment. Any product located between an antenna and receiver has even less hope of surviving a direct hit, receivers are awful sensitive. But again, their profit margin is sufficient to allow them to take this risk, on having to replace or repair an occasional receiver.
I agree 100%: Nothing is going to stop a direct hit from damaging lots of things. Lightning strikes have enormous amounts of energy (power). Even lightning rod systems (pointed or blunt) aren't going to stop every strike, and the pointed versions attract the strike to dump it into the ground system (hopefully). If your site is in a lightning prone area, they can be better than nothing, but like many things, the devil is in the details in my experience.
The goal, I think, is to limit the amount of damage of strikes hitting your power lines somewhere, or the EMP through space effects from a close, but not direct hit.
I only buy from reputable and long standing manufacturers of surge protection, because as
@WinterDeere pointed out, you want to be able to rely on their warranty/insurance, and not find out that "Acme Surge-R-Us" doesn't have a functioning insurance. (These days, I am using Eaton, Siemens, Belkin)
I would also point out that every cable coming into a building is supposed to have some sort of surge protection these days, so telephone, Ethernet, cable equipment all benefit from surge protection, preferably on the outside wall of the house.
Finally, I think the issue of a grid power electric fence charger gets overlooked. I think that they are an accident waiting to happen. I prefer solar powered electric fence chargers, and mine get air gap lightning/surge protection. Mine have survived lightning storms that blew up the ground on our main transformer, so perhaps the air gaps did provide some protection.
All the best, Peter
