Author Topic: Should I worry about grounding my PWS?  (Read 1989 times)

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Offline dalecoy

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Re: Should I worry about grounding my PWS?
« Reply #25 on: July 11, 2019, 03:21:53 PM »
I went back and forth over taking this one down or getting a new one. I may have my answer!

I'm guessing that there wasn't a strike on any of the obvious places - and even possibly cloud-to-cloud lightning.

It's a good bet that *ONE* of the two pieces is still OK.  But the only way to diagnose that is if you have a friend with a Davis PWS. 

Possible answer:  Move it all to Florida, and then buy another one.  You'll end up with either two good consoles and spare parts, or one good console and two good ISS units.

Offline SnowHiker

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Re: Should I worry about grounding my PWS?
« Reply #26 on: July 11, 2019, 03:41:30 PM »
The irony is that this Sunday will be my last Sunday here and I will be moving to Florida. I went back and forth over taking this one down or getting a new one. I may have my answer! The ground has a lot of clay and is too wet to look at it today. I may try to reset the sensor another day.
Remove the batteries and disconnect the solar panel if it has one for the move (actually you probably don't need to disconnect the solar panel assuming you pack it in a dark box for the move), that may help discharge any static.  The move should also give it plenty of time to dry in case moisture got on the board, as long as you don't hermetically seal it for the move of course.  :-)

Offline ValentineWeather

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Re: Should I worry about grounding my PWS?
« Reply #27 on: July 11, 2019, 03:42:05 PM »
I've grounded my pole after having suspected lightning issues during thunderstorms on a wide-open station. I was getting spikes on console during thunderstorms using the long-range transmitters.  I've since grounded my station with a 10-foot ground rod going about 7' deep and large enough pipe ground clamp to go around a heavy-duty 30' telepole at the base. My understanding grounding will help bleed off a potential charge that can attract lightning, especially when its the only tall object in the area.

When I relocated pole I was in a hurry and instead of doing it right and ordering a new ground sleave, I directly encased in cement. The cement makes a poor ground so needed the ground rod.
Randy

Offline dalecoy

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Re: Should I worry about grounding my PWS?
« Reply #28 on: July 11, 2019, 05:52:51 PM »
Grounding is certainly a technically good idea - for several reasons.  How much it "prevents" lightning strikes is debatable, but the answer is "probably a little bit". 

It's particularly helpful if the pole is attached to some other structure - like your house, etc.

But if the lightning does strike your well-grounded, very-conductive pole, it's still going to do damage - and will certainly "kill" the electronic components in the ISS.

One source says: "An average bolt of negative lightning carries an electric current of 30,000 amperes (30 kA), and transfers 15 coulombs of electric charge and 500 megajoules of energy. Large bolts of negative lightning can carry up to 120 kA and 350 coulombs."

500 megajoules is approximately 140 killowatt hours - or roughly the same energy as exploding 200 pounds of TNT.

Offline ValentineWeather

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Re: Should I worry about grounding my PWS?
« Reply #29 on: July 11, 2019, 06:15:25 PM »
Lightning is very unpredictable for sure. Grounding can only diminish the likelihood by bleeding off the oppositely charged ground component.
Randy

Offline CW2274

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Re: Should I worry about grounding my PWS?
« Reply #30 on: July 11, 2019, 06:30:29 PM »
One source says: "An average bolt of negative lightning carries an electric current of 30,000 amperes
Impressive until compared to a positive strike, 300,000 amps and 1 billion volts. :shock: Fortunately they're fairly rare, less than 5% are positive strikes.