Lightning Strikes

[Lucky Dog]

I have a PTZ camera that I use for wildlife viewing. Simple setup, 100 meters of POE that plugs directly into my Router.

Last summer I had a very close lightning strike that seemed to render my camera unusable.
I purchased a replacement camera, and it has been working well until a week ago, another nearby lightning strike and now the camera is not working.

I'm very much an amateur at this camera thing, and will admit I really don't know what I'm doing. But is this normal? Or is there a way, or something I can do that will help protect my camera from lightning?

I just want to watch my duck and deer.

 

[Teken]

Shielded Ethernet cable, proper Earth grounding, and a SPD. Other options given the length assuming no 120 VAC would have been fibre, shielded 12-2 / 14-2 power cable, media converter.

If 120 VAC was present at the PTZ you could do PtP wireless. The camera would still need to be properly grounded and protected by a SPD.

You’re learning the hard way first hand why shielded Ethernet cable and proper low resistance Earth grounding is paramount!

 

[garycrist]

You need a UPS for the cam and a lightning rod above the cam too as a minimum 1st.
Peruse through the link I'll embed but remember, it's the leader from the ground that
is killing you, not the lightning bolt! A "Star Ground" is what we are interested in. Who can
afford a multi-point?

Some Down-to-Earth Tips on Grounding - Radio World

Hardly a week goes by that the Wheatstone Tech Support department doesn’t get at least one call from a customer who is having equipment issues due to a lightning strike or power surge.

www.radioworld.com

 

[sdkid]

Good advice on grounding, etc.

Additionally, the OP should know that the lightning does not need to STRIKE. If the slack in an ethernet cable is looped neatly for storage, that loop of wire can generate current when the emp from lightning hits it. I lost at least 2 cameras most likely from that surge generated in the wire.

 

[The Automation Guy]

It's very common for this to occur unless special steps have been taken to mitigate the potential for power surges. This is because the network cable running to the camera effectively acts as an antenna for lightning surges. This means that strikes that are close by are much more likely to damage equipment at both ends of the cable vs other equipment not attached to such a long cable run.

Properly grounding the cable is a must. There are also lightning arrestor hardware that you can put at each end of the cable, but these must also be properly grounded to be affective. Another alternative is to use fiber optic cables instead of copper. Since the fiber optic cable isn't conductive, it is immune to these types of power surges. However the downside is that POE doesn't work across fiber either, so unless you have some sort of power supply at the camera end of the cable, using fiber optic cabling probably isn't a viable option.

 

[Teken]

Good advice on grounding, etc.

Additionally, the OP should know that the lightning does not need to STRIKE. If the slack in an ethernet cable is looped neatly for storage, that loop of wire can generate current when the emp from lightning hits it. I lost at least 2 cameras most likely from that surge generated in the wire.

It should be noted even fibre cable that is armoured can result in the same problems. Especially if the cable is coiled and placed on a server cabinet.

The induced voltage (EMF) can easily rise to 20 - 50 KVA!

Other things to consider is incorporating toroidal ferrite cores on the cables. Preventative measures can be deionizing spikes or active ion charged systems.

At the end of the day short, direct, and properly sized bonded Earth Grounding is key.

 

[TonyR]

You need a UPS for the cam and a lightning rod above the cam too as a minimum 1st.
Peruse through the link I'll embed but remember, it's the leader from the ground that
is killing you, not the lightning bolt! A "Star Ground" is what we are interested in. Who can
afford a multi-point?

Some Down-to-Earth Tips on Grounding - Radio World

Hardly a week goes by that the Wheatstone Tech Support department doesn’t get at least one call from a customer who is having equipment issues due to a lightning strike or power surge.

www.radioworld.com

Good info but the one thing that caught my eye was what appears to be a piece of steel rebar with a rusty top instead of a stainless steel, solid copper, copper-bonded steel or even a copper-clad steel grounding rod.

Maybe the image was meant to be in another article entitled "Proper Ground Rod Material."....let's hope so.

 

[garycrist]

If one looks closely, that copper wire comes in from the top right
and continues on the backside of the rebar into the ground.
Who knows what is buried under all of that. There could be
of a radial system of copper wires fanned under the earth.

 

[TonyR]

If one looks closely, that copper wire comes in from the top right
and continues on the backside of the rebar into the ground.
Who knows what is buried under all of that. There could be
of a radial system of copper wires fanned under the earth.

I agree it's likely what it's supposed to be, a Ufer ground, but it's not embedded in the concrete as is typical. Instead it may be connected underground as you say to a grid of interconnected ground rods.

That said, if I was doing my best to install the best grounding system I could achieve I still would NOT use steel rebar but instead would use stainless steel, solid copper, copper-bonded steel or even copper-clad....but that's just my opinion.

 

[samplenhold]

We asked Jeremy Hewitt, senior systems engineer for Inrush Broadcast Services, for his thoughts on facility grounding. He recommends the Ufer ground for new facilities.

“A Ufer ground typically consists of steel reinforcing rod (rebar) directly embedded in concrete. It must be at least 20 feet long, but it is not required to be continuous. If it is not continuous it is permissible for it to be joined via tie wires, welding or exothermic welding. An alternative means of constructing a Ufer ground would be to embed 4 AWG bare copper wire in the concrete.”

Fig. 2 shows a Ufer ground at a broadcast facility. The Ufer ground system is named after Herbert Ufer, a former U.S. Army consultant. He was tasked with creating an effective and relatively inexpensive grounding means for bomb storage vaults in Arizona.

 

[TonyR]

We asked Jeremy Hewitt, senior systems engineer for Inrush Broadcast Services, for his thoughts on facility grounding. He recommends the Ufer ground for new facilities.

“A Ufer ground typically consists of steel reinforcing rod (rebar) directly embedded in concrete. It must be at least 20 feet long, but it is not required to be continuous. If it is not continuous it is permissible for it to be joined via tie wires, welding or exothermic welding. An alternative means of constructing a Ufer ground would be to embed 4 AWG bare copper wire in the concrete.”

Fig. 2 shows a Ufer ground at a broadcast facility. The Ufer ground system is named after Herbert Ufer, a former U.S. Army consultant. He was tasked with creating an effective and relatively inexpensive grounding means for bomb storage vaults in Arizona.

As I acknowledged right before your post.

 

[samplenhold]

As I acknowledged right before your post.

Sorry, I did not see your post as I was posting mine.