Know a safe way to test lightning struck 1wire eq?


Hi there,

Running a Dallas SemiConductor 1 Wire Weather array.

Recently took a lightning strike that knocked out at least 2 ds18s20's and a ds9097u. (Not to mention my hard drive.)

Found some horror stories when looking for a safe way to check a lightning detector, solar sensor and temp/humidity boards on a 1wire network after a lighting strike. They are the HobbyBoards versions.

Any idea on how to check other boards before connecting and risking damage?

Thanks in advance for your help.

I have been researching the 1-wire bus from several manufacturers and it seems that many do not put any lighting protection on their 1-wire modules. If you have any close lightning strikes, it will come down the 1-wire bus if you are running it through your house.
Hi Spanky and thanks for the reply.

I hear you and found several tips for "lightning protection" and have tried some of the less outlandish. I'm almost ready to give up and relo my weather mast off the roof and give up accuracy for a bit more safety.

My main concern right now is figuring out what I have that is good vs. what is bad. Two of the sensors (humidity and solar sensor) require external voltage vs. 1wire supplied and those are the two that I suspect most. What I hope for is someone to lead me to is a safe "gate" by which I can connect the suspect boards.

Barring that, I'll have to hope that I can send them out and have someone check them out. I consider myself lucky, it didnt get my wind pagoda (one of the highest points).

Again, any help appreciated!


You can hook the sensors in question up to the 1-Wire network without external power to see if they are still working. If you remove the jumper on the board they will use parasitic power (even though we don't recommend running them in that mode) and even if something is shorted on the board it won't hurt your 1-Wire network. If everthing checks out OK on parasitic power then you can add external power back to the devices and see if they are still OK.

Hi Eric,

Thanks for the guidance ;)

Just for boards requiring supplemental power (Humidity and Solar):

I understand (and am relieved) that the sensor aspects can be checked by connecting to the the 1wire net w/o connecting the supplemental voltage.

However, in the better safe than sorry dept...Is there a safe way to check the circuitry associated with supplemental voltage without connecting it to the 1Wire net? I'm pretty sure that my last strike came down the 12 volt supply line or the shared ground.

I assume (danger) that I could take my regulated 12 volt power supply and safely connect 12volts to the supplemental supply w/ ground without connecting the data line. If so, are there some test points (and voltages) on the boards that you can advise of to verify "safe to connect" conditions for the supplemental v side prior to connecting it back to the net?

As always, thanks for your assistance!
Go Hobby-Boards! :)


If you have a multimeter this will be no problem. Like you said, just hook up the supplemental power via the screw terminals and leave the data line open. Then you can check the output of the voltage regulator. The easiest way is to put the negative lead on the ground screw and put the positive lead on the leg of the humidity sensor closest to the edge of the board. You should read +5v (or close to that) if everything is OK. If it doesn't read +5v then look for components that look like the magic smoke has been released (most likely REG1) ;).

For the solar board you can use the same procedure just use the hole in the board where the leg of the humidity sensor would be soldered if it where there.

Let me know how it goes.

Hi Eric,

Welp, the solar sensor (Utmost highest part on mast above the house) has given up the ghost.

Connected my humidity sensor and got the target volts. Connected my Solar sensor (Now know as toasty1 :) and seen the wispy black death tendrils of D1 wafting softly through the evening air.

Lighting detector checks out fine.

Final tally,

Power supply which shows 29VoltsAC between + and -

1 hardrive,1 ds9097u, 3ds1820's, 1 solar sensor = Can I get outside to get the mast down before this storm arrives!

Thanks Eric, I sure appreciate the info.


Did the DS2438Z on the Solar board show up on parasitic power? If so we may be able to revive the Solar board (aka Toasty1) with a few transplants :)

Hi Eric,

In all honesty, I didn't even check. I checked out the supplemental voltage issue first. After that, I literally went up to the roof and took my mast down and set it back up in the yard. We are in for storms the next few days and I figured I have pressed my luck enough.

My wife has offered to help me trench a cable path about 100 ft (or so, hehe) out from the house. I don't think she knows what she's in for. :D

Def. haven't written the Solar Sensor off yet. I'll check with parasitic supply and if it takes off, welp, needless to say, if I can't fix it, I was hoping that I could send it to you for your professional service. (Specially after my bungled attempt to assemble your kit in the first place. :) I'm going to give it a go though. I'm sure you'll hear from me then. (Sorry in advance)

You'll probably see me on here and there bugging folks for suggestions on grounding and such. I've got a Lacrosse 2310 coming in a few days and I'll be busy relocating my best buddy the 1wire and installing the new 1 too.

I probably wont get back to the repairs until after you return from vacation. Best wishes with that for a safe, fun filled, relaxing vacation.

Once again,

My sincerest thanks,
Until we "meet" again,
Best regards,
Hi Eric,

Just got around to finish testing my suspect boards. The humidity temp and even the good ol' "toasty" solar detector works fine using parasitic power. :)

I think I'm going to try to leave the solar using parasitic since the damaged components seem to be limited to the aux power circuit. (D1 4 sure, maybe the regulator too.)

If it causes too much pull on parasitic I'll be bugging you for some parts.

Thanks again for your help.


That sounds good. As long as it seems to work on parasitic power then run it that way until something else fails.