Zapped! The saga continues
August 21, 2010—Well, I feel a lot better now that I have repairs scheduled. In a couple of days, Coach-Net will send a truck to tow Skylark the 106 miles to Town & Country Ford in Alamosa, Colorado, where I have a Tuesday appointment. Once they get the engine running and fix whatever else turns up, I can rendezvous with Mike Sylvester to have the coach repairs done. I'll still have to find a place to replace the CB and FM antennas and wiring, but that's a lower priority. The main thing is, I don't have to be towed to Albuquerque!
Another thing that has done wonders for my mood is the continuing support of fellow RVers. I can't tell you how much I appreciate all the encouraging emails that have come in.
Meanwhile, Apple just delivered my new 27" iMac (a free in-warranty replacement for my old 24" machine), so I have something else to be cheerful about. This big 2,560 x 1,440 screen is absolutely fabulous! And moving over everything from my old iMac was a matter of hooking up one cable, clicking one button and waiting a couple of hours for 212 GB of programs, folders, files, emails, account settings and so on to be copied over. When it finished up, the new machine worked exactly like the old one, except for the larger screen and faster speed. Say what you will about Apple, they know how to make a complicated process simple and painless.
So while I'm enjoying my new computer and waiting for the tow truck to show up on Monday, let's talk about what happened and why.
How did it happen?
There's still a surprising amount of controversy about the details of how lightning is generated, but we needn't worry about that. The basic facts are these: a negative charge (an excess of electrons) builds up in the clouds of a rainstorm; it causes a positive charge in the closest points below the cloud; and when the electrons in the cloud get too numerous and too crowded, some of them decide to "emigrate" to the ground. (Or in some cases to another cloud where it's not so populous.)
Electricity normally doesn't like to jump air gaps, but when you get up to several hundred million volts, it can superheat the air to around 50,000° F.—five times hotter than the surface of the sun!—and thus make it conductive. Air that hot expands instantly and dramatically, creating the shockwave that we know as thunder.
So those are the basics: a bunch of electrons in the cloud looking for an easy path to ground. An easy path is something that's taller than the surrounding terrain and is a good conductor of electricity. That could be a tree, a person holding an umbrella... or an RV that's plugged into "shore power" and has an antenna on the roof.
Here's where I made a mistake: I was plugged in during the storm. That made it easy for electrons to get from the cloud to ground, traveling via my heavy-duty power cord. Matter of fact, there was a tree only about ten feet away that was taller than my rig + antenna... but lightning preferred a steel antenna, an aluminum-covered RV, and a copper cable to a wooden tree. The easy path always wins.
Dos and don'ts
So the first lesson from my experience is: when you hear thunder in the distance, unplug! Disconnect the cord at your RV, if possible. That's much safer than leaving a long power cord trailing, with its exposed plug only an inch from wet ground.
While reading up on lightning after the event, I came across a very good article on "Lightning and RVs." That's where I got another good tip: during a thunderstorm, retract your leveling jacks. Those four metal legs reaching down to the ground make you more attractive to lightning. I don't have levelers, but lots of RVers do, so it's good to keep in mind.
Lightning has a tendency to destroy things that are plugged into 120VAC outlets, expecially devices that are drawing power all the time, such as microwave ovens, TVs, video recorders and the like. Computers are common victims, too. Now, you may not be able to easily disconnect a built-in microwave in your RV, but you can unplug your computers and similar devices during a storm.
I didn't disconnect... but in my case, nothing plugged into 120VAC was damaged. Luck? Maybe—lightning is so unpredictable that it's hard to be certain—but it's likely that my surge suppressors had a hand in preserving the appliances, such as my computer, that were plugged in and running when the lightning hit. I have two lines of defense: my Surge Guard whole-house surge protector stops surges coming in from either the shore power cord or the generator; and my Zero Surge 8R15W computer surge protector stops surges from getting to my computer and its accessories.
I particularly recommend the Zero Surge products. There are a lot of crappy surge suppressors on the market, most of them using technology that can do more harm than good, that wears out in a few years... and what's worse, can explode or burn when hit by a really big surge. (I've seen that happen, and it's scary.) Zero Surge uses unique technology that prevents that from happening. I did some consulting for the company back in my electronics-tech days, and I dug deeply enough into their engineering to be convinced that there's nothing like it on the market. (No, I don't get paid for saying that.) At $200, their boxes aren't cheap, but in my humble opinion they're well worth it when you consider the value of the equipment you're protecting.
But let's be frank: nothing can stop a direct hit by lightning. For example, some people think their tires will protect them, because everybody knows rubber is an insulator. Well, so is air... but if lightning can jump hundreds of feet of air from a cloud to the ground, how hard do you think it is for it to jump six inches across the wet, dirty surface of a tire? This photo shows exactly that, using lab-created lightning.
Similarly, if the full power of the lightning that hit my rig had gone into the shore power cord, that cord would have been exploded just as my CB antenna was, and everything connected to it would probably have been fried, surge protectors or no.
In fact, if I'd had a typical fiberglass-bodied RV, that's probably what would have happened. But my Lazy Daze is sheathed with heavy aircraft-grade aluminum, an excellent conductor of electricity that literally forms a protective shield around the contents of the coach. That's why my hair didn't stand on end just before the strike.
My best guess—and it's only a guess—is that most of the energy of that lightning bolt traveled through the aluminum skin of the rig and jumped the tires to get to ground. Only a little (relatively speaking) went through the shore power cord... enough to weld together the contacts of my transfer relay, but not enough to overcome my surge suppressors.
Dead in the water
Unfortunately, one of the items not protected by a surge suppressor was the motorhome's engine computer. Engine computers are pretty tough these days—they have to be, to work reliably in the hostile environment under the hood—but all that electrical energy hitting the front of the roof (and some coming down the antenna wire) was apparently too much for this one.
The odd part is that it worked right after the strike—the engine started right up and run smoothly, as I mentioned on the first page of this account. But then a week later it was dead. Since the lightning had fried my ScanGauge II reader (in itself a bad sign, since it was connected directly to the engine computer's diagnostic port), I couldn't "read the codes" to find out what was wrong. So I borrowed a mechanic's ODBII reader from a friendly local NAPA auto parts store in Chama, NM, and tried that. No dice: it couldn't even connect to the engine computer, much less read out diagnostic codes.
I've heard disturbing stories from several people of lightning causing damage that appears months later. One woman was told, "When you get it running, sell it. Problems just keep appearing as system after system starts failing." Lighting is quirky seems to be the general consensus. I certainly hope nothing like that happens to Skylark! While I do have insurance, it won't pay anywhere near the replacement cost of this rig and all its improvements... so I earnestly hope that I'm not going to see one system after another failing down the road.