Not sure of the correct terms, but I’ll be running track power. Up to now, for testing, I’ve brought out the power supply when needed. But I realize this becomes a hassle. I have a way to run the wires from the track to a closet inside so I can leave it hooked up all the time. But I want some sort of electrical throw to isolate the supply from the track when not in use, just in case of lightening. Suggestions?
Just install a single pole, single throw switch in the leads to the track to isolate the transformer. Whenever the clouds threaten, just throw the switch.
For extra security, and extra money, though no much, consider a double pole, single throw switch. A common house light switch works well in this application.
You also want to unplug the inside transformer. A standard heavy duty double pole light switch will work best, but if lighting strikes close enough to the track and the transformer is still plugged in, it will arc across the points of the switch and still fry the transformer.
The way I figure it, the utility companies have been trying for decades to try to protect their equipment from lighting strikes, with far more cash thrown at it that every member of this forum combined, and they still have no real answer.
Consider that the average surge suppressor you purchase with that wonderful however many thousand dollar guarantee has a normal clamping time (response to the surge) of about 5-6 nano seconds. Electricity travels at about 1 foot per nano second. That is why some computer manufacturers provide such long power cords, to allow the surge suppressor to clamp before the electricity flows to your compuuter - in theory. Maybe it can save your equipment, maybe not.
My recommendation would be a plug and socket for the DC side to the track that can be unplugged from the transformer and unplugging the transformer from the wall. I have seen lighting jump 6’ spans. When it comes to lightning, there are no guarantees.
Bob C.
How can a switch stop lightning when it has traveled over a mile from high in the sky and then you want to stop it with a one inch open circuit???
I have seen lightning hits and it traveled from a shed which had no connection of any kind to a house and just travel in the ground to the house.
Path was shed roof metal flashing to downspout, then ground travel(created a trench) to the house. Owner lost a garage door opener and a light.
I feel a lightning rod to attract the energy would be a better method as you would give the lightning a predicted path away from your trains. This is what I see on high buildings in Boston. It is cool to see the lightning hit the pointed rods.
Dan is right.
No switch is going to protect you. No surge protector is going to protect you.
I know from personal experience 
I had lightning strike a tree. It jumped 10 feet to my shed in one direction, burning it down to the ground.
It jumped about 20 feet the other direction, to an extension cord.
It ran through the extension cord into a ground fault protected circuit for a yard light, giving it a path into the house.
Once in the house, it toasted everything electronic plugged into the wall. TV’s, computers, game systems, DVD players and even the microwave. All but the microwave were on surge protectors.
An electric outlet cover in the kitchen blew off and hit the oven 15 feet away.
The phone box is on the back of the house. I found the cover to it 30 feet away. It vaporized all the wiring in the box.
It was the only lightning strike of the day. It fried a neighbors well pump a quarter mile away.
Their neighbor across the street was working in his wood shop. He was standing a couple of feet from his table saw and received a strong enough shock from the saw to put a burn on his arm where the electricity entered.
Ralph
Tom Ruddell (I believe no longer in the hobby) wrote an article on his experience and made some recommendations. I followed a few of them when I built my railroad, but rarely put the protections in play because there really is nothing you can do to fully protect yourself.
Where my track enters the house there is a 4+ foot lift-out bridge. In theory, I would remove this when not running trains to keep an air gap between the track and house. In practice it’s only removed when in the way. There is a second lift out bridge just inside the house that is almost always open.
When I was wired for track power my power supplies were in the house. Malibu low-voltage lighting wire carried the DC to a connector on the outside of the house. There is a second connector 3 feet away that is wired to the track. When running trains I installed a jumper cable between the two to complete the circuit. That part of the plan I did follow pretty religiously and is still disconnected today as I run battery power nearly exclusively now.
Unfortunately, Ralph’s experience is pretty typical. If you get a close by hit stuff is going to get damaged. When I was young and uninsured I’d run around and unplug all my electronics at the first rumble of thunder. I usually don’t bother any more as everything is insured.
My railroad is really the least of my worries. I have large ham radio antennas up in the air. They will attract and bring lightning to the house. The tower is grounded and the cables all have disconnects where they enter the house, but if it gets hit there will be damage.
Protection from a direct lightning strike is difficult at best. Protection from a surge in the lines from a near strike is easier. I’m using quality surge protectors (not a $10 power strip) with a picosecond response time on my electronics at home. On the low voltage side of your power supply a simple air-conditioner, outside type enclosure with a switch or reversible fuses would work great, and they are cheap at about $10.
(http://www.homedepot.com/catalog/productImages/300/27/27abb498-ae2b-41c3-b779-be0daf024a87_300.jpg)
A nuther good argument for battery power.
Did I say that out loud? Again? 
Steve Featherkile said:
A nuther good argument for battery power.
Did I say that out loud? Again?
Are you trying to start trouble, again? 
is it worth putting a ground rod in and hooking the layout too it?
Dick
You would have to have a way to disconnect the ground when the track is powered. In the US code reads that all ground rods must be connected together. FWIW
The following PDF is on Tom’s lighting strike.
Tom Rudell’s - Lighting: An Opportunity to Start Over. (PDF 739.26KB)
Thanks Steve. He also did an article for Garden Railways.
now i’m confused if I put a ground rod in for railroad and its 50ft from my house
I still have to run a wire to the house ground?
Richard
Technically yes, to comply with code. There are good reasons but I don’t know the theory well enough to try and explain other than to say the potential of the ground can be different from point to point and it would be possible, in some situations, to develop current between two ground rods.
That being said I have three known rods that are not connected. One for the power/phone/cable at the entry point. One at the base of my ham tower about 20 feet away and another for my ham shack another 20 feet away. The tower rod and the ham shack rod are connected through the shield of the antenna coax, but should really have a bus bar at ground level. This is probably why I sometimes can feel a tingle of electricity on the antenna connectors.
Jon Radder said:
Technically yes, to comply with code. There are good reasons but I don’t know the theory well enough to try and explain other than to say the potential of the ground can be different from point to point and it would be possible, in some situations, to develop current between two ground rods.
That being said I have three known rods that are not connected. One for the power/phone/cable at the entry point. One at the base of my ham tower about 20 feet away and another for my ham shack another 20 feet away. The tower rod and the ham shack rod are connected through the shield of the antenna coax, but should really have a bus bar at ground level. This is probably why I sometimes can feel a tingle of electricity on the antenna connectors.
Do ya think??? I hope they aren’t the worthless 4’ long ground rods from Radidio Shack. Grounding your antenna switchs to the ground rod outside your shack is a good idea as well as your chassis grounds. But they should all be interconnected to your A/C ground. You can use a nearby metal water or boiler pipe rather than running a ground wirs or strap. Remember the ground wires can become resonant. 73 Jon n3xge
Interconnecting the ground rods will reduce the ground potential between the rods. For example on dairy farm applications, ground rods not interconnected, (I believe under normal circumstances), will tingle the cattle through their hooves in muddy areas (not like Chris Mathews).