If the charge is not dissipated, it will actually attract a strike and can send it through the buildings electrical system. The primary reason for “grounding” a weather vane is for lightning protection purposes.
Hopefully you now understand why you need to do one of two things when it comes to grounding your weather vane: A) install a full lightning protection system, or B) do nothing at all. The whole area of lightning protection is a unique field, where most electricians and other contractors have very little, if any, expertise.
This is because lightning protection is NOT part of the National Electrical Code, which all good electricians know forwards and backwards. Click Here for a detailed explanation by lightning protection expert Alexander Easley.
A building site, whether it is a house, a garage, a barn, or whatever, may have several grounding systems. This is the wire that connects a ground electrode, sometimes a water pipe, to the breaker panel and is routed to all the receptacles.
The one we want to talk about now is the lightning protection system and your weather vane. The negative ions build up as the air moves across the earth.
This is similar to static electricity such as sliding your feet across the carpet and then touching something and drawing an arc, and as you know, lightning is more powerful. If you do not have a lightning protection system installed, then a ground connected to your weather vane is not needed and may even be damaging during a storm.
The lightning protection system ground terminals shall be bonded to the building or structure grounding electrode system. For information on how to install the lighting rods and the grounding electrode system see NPA 780, Standard for the Installation of Lightning Protection Systems.
Re: weather vane groundingThankyou for the input guys... I need to get a copy of that NPA 780 I connected the #4 ground wire right to the weather vane with a copper pressure lug...
The NPA 780 calls these devices “air terminals”. Re: weather vane grounding you are attempting to provide lightning protection per NPA 780, an air terminal is required, unless the weather vane is 3/16” thick.
Or greater shall require only connection to the lightning protection system. 220.127.116.11 Such connections shall provide a minimum of two paths to ground.
The NEC has no rules concerning weather vanes or lightening protection systems. This is an antique weather vane off some old farm house in up-state NY and it comes with no instructions.
But in a thunderstorm the other night I got a little nervous because my bed is directly under the weather vane. The manufacturer's instructions suggest connecting that 8 AWG conductor to an 8 AWG conductor that is run directly to the grounding bar of the main service rated panel.
Through the structures attic and down the wall into the panel with sweeping curves in the wire and no sharp turns. This is in thoughts of lightening strikes being invited to hit that church steeple. That is as close to our situation that I can get.
Sberry, the design of a metal weather vane is generally believed to be an invitation of a lightening strike. It is not a good idea to just add a ground rod here and there throughout a building.
Sberry27, I think your suggestion of a plastic weather vane is the best idea on this posted thread. This might be a good time to explain the real purpose of a lightning rod.
That does the opposite of the lightning rod, in that is forces a small build up which “pops” off periodically, unnoticed by the radio listener. Without it, the potential could not build up and would bleed almost continuously, created static in the radio.
Without the addition of a rod, I would suggest you leave it alone as far as grounding, unless someone else posts a good reason for it. The manufacturer refuses to give tech specs (probably liability).
Can I just run a wire from the cresting to my electrical panel's grounding rod? Re: grounding a weather vane #445135 03/24/0807:05 PM03/24/0807:05 PM Joined: Sep 2002Posts: 10,199 Welland Ont.
Re: grounding a weather vane #445138 03/24/0809:43 PM03/24/0809:43 PM Joined: Mar 2004Posts: 10,197 New England Joined: Mar 2004 Posts: 10,197 New England I would just leave the thing as is.
Re: grounding a weather vane #445142 03/31/0803:00 AM03/31/0803:00 AM Joined: Jun 2003Posts: 205 Des Moines, Iowafigaro enthusiast Joined: Jun 2003 Posts: 205 Des Moines, Iowa All good advice here. Experts | Email Us | Disclaimer | HandymanWire homeArticles | We welcome your feedback.
If all you are doing is adding a little extra height to your home and, NOT grounding it, then it does not matter too much if the finial is copper, wood, fiberglass, etc;. Everything changes if you decide to ground an item and unless it is part of an overall lightning protection system you may be inviting trouble.
Bob Dylan famously sang that “you don’t need a weatherman” to determine wind direction, and he was right. For some, a weather vane is an essential part of a DIY weather forecasting station.
The iconic look of a rooster, pig, or other character sitting atop a spinning arrow is timeless, nostalgic, and fun. People have placed weather vanes in chicken coops, sheds, houses, barns, and living room mantles, to name just a few locations.
Smaller weather vanes tend to cost less; these structures look great on top of sheds and chicken coops. Some weather vanes ship with a mount and all the hardware needed for roof installation.
The entire purpose of a weather vane is to rotate and show wind direction. While this can be hard to verify when purchasing online, a dive into the product specs should clarify any questions you have about the spin or rotation of a weather vane.
There are several metals to choose from, but whichever you select, it should be durable, weather resistant, and long-lasting. Any weather vane made from steel should have a powder coating to protect it from the elements.
An aluminum weather vane may feature some form of protective coating, like satin black enamel. On a poorly made product, these components can easily wear out or break.
It may feature a flying pig, fish, chicken, mermaid, or other figure that rotates in the wind. The top may serve as a wind pointer, or it may sit atop a pointed arrow.
Standard on the majority of weather vanes are directional that point out north (N), south (S), east (E), and west (W). These remain in a fixed position while the top rotates so you can easily tell at a glance which direction the wind is blowing.
Holding it all together is the assembly rod, the skewer to the weather vane swish nabob. Inexpensive: For $30 to $50, you can buy a compact weather vane with a simple design and a light build.
The tops of these inexpensive weather vanes are often flat as opposed to hollow or solid. Weather vanes in this price range are best as in-house decorations or toppers on a smaller structure like a shed or chicken coop.
The majority of buyers should find satisfaction in this middle price range. Weather vanes in this price range tend to be larger and are often made of copper.
For the money, you can expect solid-body designs and multiple layers of protective coating. Weather vanes at the top of the price range are best suited for larger barns and similar structures.
When copper ages, it forms a greenish outer layer called a patina. Those crafted from aluminum largely use recycled metal, which is a plus for those seeking a green option.
Mounts can be fixed or adjustable to fit a variety of roof types. If you frequently experience high winds, consider buying a heavy-duty mounting package.
A protective coating can help to shield your weather vane from fading, rust, and other weather-related issues. If you go this route, you will have the added bonus of knowing that the weather vane is properly mounted and able to withstand whatever Mother Nature throws at it.
Unless these instruments are wireless, however, you won’t be able to place them on a roof and receive much information from them. Similarly, if it suddenly shifts to show wind from the south, it may indicate that warm air is headed your way.