Lightning Diverter/Arrestor Snakeoil ?

bullbreaker · Aug 8, 2013

Anybody here ever use a "Lightning Diverter" or porcelain " Lightning Arrestors" , on their electric stock/horse fence units ? The claim here though not 100% fool-proof there suppose to "save" fence chargers . Never have used them on mine and was wondering if they work or are just snakeoil or cure-all tonic.
Also on AC fence chargers are You's running surge protectors ?

Lightning Diverter Each
Lightning Arrestor -Porcelain Each

Thanks in advance !

Boone

DT86 · Aug 8, 2013

I use those exact ones on one charger that is AC. Any time the lightning hits the fence the protector is toast but it saves the charger.... usually. On my solar set up, which uses the same exact charger but with solar panels and a deep cycle battery, I haven't put one on yet but I should.

One time lightening did get my AC charger, even with the lightening arrestor in place. The charger lives outside on a pole in a box that looks like a bird house with a plexiglass front. It looked like someone had smashed both the housing and the charger with a ball bat, the parts were blown in a simi circle about 20'. Luckily it was under a one year unconditional warranty. I took the charger back to the store in a five gallon bucket because it was in so many pieces. No questions asked I left with a brand new one.

Ken · Aug 8, 2013

Consider automotive spark plugs. The power company I used to work with used Equipment made by G.E. and spark plugs used on power input and where attached to signal with in the substation.
And still use around my shop with wire attached to metal roof. grounded to ground rod.
ken

DT86 · Aug 8, 2013

Ken said:
Consider automotive spark plugs.

I'm just asking here but.... Really? If lightning will blow one of those apart with a ~3-4" gap what will a spark plug do better?

Not doubting you but I don't understand.

Ken · Aug 9, 2013

DT86 said:
I'm just asking here but.... Really? If lightning will blow one of those apart with a ~3-4" gap what will a spark plug do better?

Not doubting you but I don't understand.

The gap will form a constant bridge until arc is discharged to ground. Then be ready to go again if lightening is present.

The alum. will do same but melt in the arc.

Smarter heads than I decided to thread the cabinet for spark plugs . and connect to the power line 3 phase and 3 spark plugs .This is a old school design now fancy blue dual diodes do same but only once then have to replace. When hit by high voltage.
ken

daveshoot · Aug 9, 2013

The best way to lightning insulate is a gas-filled spark gap. This allows the relatively low voltage to power the fence. When the surge hits, the gas condenses and shorts to earth ground, sumping the surge to the dirt. The good ones have induction coils and metal oxide varistors (MOVs) behind the spark gap.

This works as well as your earth ground hardware. Should be an 8' copper clad rod, minimum of 8' away from the electronics you're protecting. You don't want the discharged surge getting right back onto the wire.

These protectors can still blow, but the point of the spark gap is that it restores to new condition unless it gets a hit it can't handle; then it dies to save the electronics.

techman · Aug 9, 2013

Devices such as these serve a useful purpose. While they would be blown to kingdom come if there were a direct hit, just like a lightning rod on a house, they serve the purpose of discharging static build-ups before, and to prevent a lightning strike. When a thunderstorm is in the area, voltage gradients can build up in the atmosphere. These gradients can be up to several hundred volts/meter above ground. This build up can become a problem with a long fence as it acts like a collector wire. The discharge spark gaps will discharge the energy before it builds up to levels that could result in a strike. An additional advantage is that light strikes to trees or the ground in the region of the fence can result in voltage, in the kilovolts, can be induced into metallic structures, like a fence. These induced voltages will also be bypassed by these devices.

paul