NA single-device surge suppressors

Let'sgoflying!

Let'sgoflying!

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Dave Taylor
Has anyone done any research and decided which ones are best in particular situations?
(I have a few locations which only have one printer or one computer...and we get direct lightning hits every summer)
This might turn into a thread like my 'find the perfect airplane for 100K' thread; not completely possible :D
Let me know your thoughts on these, thanks.
 
Bonanza. Somebody was going to say it...

:)

I just check specs on energy dissipation (Joules), clamping voltage (lower is better) and clamping time (shorter is better) and pick one. I only have to buy new every couple of years and I'm always surprised by the improvements between purchases.

John
 
Not that this is much help, Dave, but...

...I don't have any electronics anymore that are AC. They all have AC/DC transformers. Laptops, printers, phones, etc. I still use surge suppressor power strips but they're really not needed. Sure the xfr will blow but the electronic device itself should be safe.

I think, anyway...
 
Lightning is our biggest problem, (not mains surge). For years we have run around before a storm unplugging everything. And forgotten something or gotten there too late, usually we lose 3 devices (phone/modem/computer/printer, etc) each year.
Think only little house on a large prairie with a storm target on the roof.
Probably need lightning rods on the buildings. Maybe a cordon of storm-activated, automatically-deploying helium balloons, with copper laced tethers.... surrounding the place.
I suspect there is no reasonably priced surge suppressor that is going to do what I need.

Ancillary question which I have often wondered: If you take multiple SS's and connect say 5 inline with the protected device (phone/computer etc), is there any additional benefit ie would there be better lightning protection if it had to pass through multiple similar SS's vs just one?
 
Don't forget, Dave, you'll need surge protection on your phone lines too if you're still wired at home.

I have a whole house surge protector out in the barn that I'd gladly send if you want to try it. Gratis.

I'm heading out of town for a few days and likely won't have time to take a photo of it before leaving but will when I return.
 
timwinters said:
Don't forget, Dave, you'll need surge protection on your phone lines too if you're still wired at home.

I have a whole house surge protector out in the barn that I'd gladly send if you want to try it. Gratis.

I'm heading out of town for a few days and likely won't have time to take a photo of it before leaving but will when I return.
Click to expand...

Daisy chaining the strips probably won't help much. But, using a whole house suppressor and THEN adding strips or single outlet protection is a better "defense in depth" approach.

Also protect every wire that going into the computer and it's peripherals. A direct lighting strike is going to do damage. But most of the computer equipment that gets damaged is by induced spikes. It's like a transformer but with the wires strung out instead of wound. Lighting strike anywhere close makes an EMF pulse, induces current on all the wires which then spike the connected equipment. So put surge suppression on the cable going into your modem (if you have one), on your network wiring, and make sure that any USB or other wired equipment that plugs into the computers are also surge protected.

John
 
I already have a 30' metal windsock pole, but can never get the lightning interested in it; lightning seems to have developed a taste for my sensitive, expensive electronics.
 
Don't forget the washer and dryer. Those are what's cost me for not having surge protection. Lesson learned.
 
I did not imagine lightning could get those, have never unplugged them. Maybe yours have fancy electronic controls and mine are bronze age? Do they make suppressors for such beasts? Are you lone house onna prairie too?
 
Surge protectors and even most lightning protectors aren't going to help with a direct strike. The best they can do is help protect certain things coupled to nearby strikes.
I've lost everything that was plugged into my phone line (phones, dsl modem) and also my well system (it's a VFD from the house down into the well).

Most cheesy point of use surge protectors are typically a couple of MOVs. Sometimes if you're lucky you'll find a choke in there too. They're better than nothing, but don't count on them much.
 
MOVs and then the glass gas discharge tubes for the big hits.

Lots of people buy the power strips with the MOVs in them and no monitoring circuit that the MOV is working, so the MOV gets obliterated (literally - burnt to a crisp and blown all over the inside of the power strip in tiny burnt bits) by a nasty surge above their ability to handle it, and then the NEXT surge takes out the stuff plugged into the strip.

Direct strikes, all bets are off. I've seen entire power strips blown to little bits, coax vaporized, not melted... g-o-n-e, wall plugs blackened behind MOV+gas discharge protected gear (those devices send that stuff to ground, so the plug wiring and wiring in the walls sometimes gets crispy after the protectors do their job, and you have to ring out all the in-wall wiring with a megger afterward to make sure you don't have charcoal for conductors inside walls with no insulation after an "event"), satellite receivers with all of the discreet components blown off the circuit board so they made a nice stinky rattle toy... Holes blown in the roof of my garage, lawn edging welded together all the way to the tree that took the return strike path, tree trunk split from bottom to top... You name it. Direct strikes are bad news.

The good news is, insurance usually covers it, amazingly enough.
 
denverpilot said:
MOVs and then the glass gas discharge tubes for the big hits.

Lots of people buy the power strips with the MOVs in them and no monitoring circuit that the MOV is working, so the MOV gets obliterated (literally - burnt to a crisp and blown all over the inside of the power strip in tiny burnt bits) by a nasty surge above their ability to handle it, and then the NEXT surge takes out the stuff plugged into the strip.

Direct strikes, all bets are off. I've seen entire power strips blown to little bits, coax vaporized, not melted... g-o-n-e, wall plugs blackened behind MOV+gas discharge protected gear (those devices send that stuff to ground, so the plug wiring and wiring in the walls sometimes gets crispy after the protectors do their job, and you have to ring out all the in-wall wiring with a megger afterward to make sure you don't have charcoal for conductors inside walls with no insulation after an "event"), satellite receivers with all of the discreet components blown off the circuit board so they made a nice stinky rattle toy... Holes blown in the roof of my garage, lawn edging welded together all the way to the tree that took the return strike path, tree trunk split from bottom to top... You name it. Direct strikes are bad news.

The good news is, insurance usually covers it, amazingly enough.
Click to expand...

Just to add, here in stormy central Florida, I've seen holes blown in concrete blocks and copper plumbing pipe vaporized with pin holes blown in other parts of the plumbing, dimmer switches blow fireballs across the room, and ground wiring (think #1 braided copper) burned in two where the wire turned a corner. An actual lightning strike is a massive amount of energy.

John
 
Does a knife switch provide, in theory, better lightning protection (when off, of course) than other types of switches? Seems like there might be a bigger gap to jump.
 
Let'sgoflying! said:
Does a knife switch provide, in theory, better lightning protection (when off, of course) than other types of switches? Seems like there might be a bigger gap to jump.
Click to expand...

Maybe.

High voltage likes to jump out of things at pointy corners and edges. Knife switches have lots of those.
 
I'm the Liebert rep in Colorado. We sell Emerson Network Power surge suppressors. At my house I have one of these wired into where the electrical service enters my home. This protects my entire home from surge events. Before installing it 6 years ago I had nearby lightning strikes knock out a TV and a computer printer on separate occasions. Since installing it I've had no problems. I'd go outside and take a picture but we're being blitzed by a snow storm right now. The unit I'm using is in the lower right in the image below.

Here's the web page for these products: http://www.emersonnetworkpower.com/en-US/Products/SurgeProtection/Panelmount/Pages/510Series.aspx

510%20Series%20-%20group%20pic_large.png
 
Let'sgoflying! said:
Does a knife switch provide, in theory, better lightning protection (when off, of course) than other types of switches? Seems like there might be a bigger gap to jump.
Click to expand...
Probably not. You're talking about a voltage that jumped the gap from the clouds to power lines, looking for ground. That inch or so gap may look like nothing to lightning. One downfall to having a knife switch is speed, that's why modern switches have springs or even electric actuated coils to minimize arcing.
 
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You're talking about a voltage that jumped the gap from the clouds to power lines, looking for ground.
Click to expand...

I have recounted here, similar thoughts on that very subject. Indeed - lightning can do whatever the h. it wants!
However, I was thinking maybe 90% of 'strikes of concern' might be partially dissipated by the time they get to the powered equipment. Of those, it seems the bigger the gap, the more protection I would be getting on those strikes. The knife switch I saw last week (it has springs too, Glenn) had about a 3" gap between the two connections. Surely that is more protection than in a SquareD disconnect?
 
Lightning is nasty stuff. Millions of Volts, hundreds of thousands of Amperes, both for short periods of time. Friends on the next street got hit (directly) and they lost a bunch of stuff. Surge suppressors wouldn't have helped. Yes, this was years (decades) ago when we lived in Colorado.

A guy I worked with at Martin Marietta Denver Aerospace had "lightning strike detectors" on various fence posts around his house up in the hills. Lengths of copper wire formed into large, loose coils. The current induced by a nearby strike would cause the adjacent turns of the coil to repel each other and the wire would be straight. Nasty stuff.

Another sea story - also from my time at Martin. MMA had built the heliostat array for a large solar power plant near Barstow, CA. Many (many, many) steerable reflectors that focused the sun on a steam generator. We got a call (my boss was the main point of contact within the company for EMC issues, it was fun working for him) that a nearby (about 3 miles distant, IIRC) ground strike had taken out line drivers and line receivers throughout the array (we're talking acres of reflectors). A quick bit of questioning showed that the wiring was run in metal conduit, but the conduit wasn't electrically terminated at the ends. The wiring simply left the conduit to go to the line driver or receiver. What happened was that the field from the lightning strike induced large currents in the conduit and when that current hit the open ends it had to go somewhere, and that "somewhere" was the wire leaving the conduit. Dead hardware all over the place.

Lightning is nasty.
 
I like that conduit one.

At tower sites the entire game is not to try to stop the voltage from getting into nearly everything, the game is to get everything to rise and fall in voltage at roughly the same rate and provide plenty of low resistance paths to ground as possible, all bonded together with equally low resistance or better conductors, to give all that current a whole bunch of places to go without encountering sharp bends or angles.

If you can get most of the hit to ground, you can deal with the rest.

Pretty typical to see a tower surrounded by many many copper clad ground rods driven deep, all connected together by 2 AWG copper and then bonded directly to the tower let with a wide copper strap, cadwelded to each leg, and then bomded to another ring of 2 AWG copper around the building with tons more rods. Building entrance is a big flat copper plate with holes drilled into it for polyphasers (essentially gas discharge tubes for RF cabling) and an even wider flat copper strap running down the outside of the building and bonded to the 2 AWG "halo" ring around the building.
Similarly inside the bundling there's often another overhead halo ring of copper and all of the rack cabinets and freestanding racks are bonded to that one with flat copper strap.

Now that I've seen the destruction unleashed by two residential direct hits, I'm one of the paranoid ones that even has a copper plate entrance panel at home for the ham shack and rods driven at that entrance (but no building halo) attached via wide straps. It need beefed up to the commercial site standard when the tower eventually goes up here.

Bigger problem out here is the overhead power lines getting nailed. That happened tonight and tripped the upstream sub-station offline for about two to three minutes.
 
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