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Discussion Starter #1
I have no official word on this but with the lightning storms we have at the moment I would imagine it would make sense not to leave the car plugged in if there is a lightning risk overnight.

I realise this might be inconvenient but I have had computers and TVs fried before and I hate to think of how much a repair might cost if the car got zapped! :eek:
 

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Must admit I didn't think of that last night - but then who thinks straight at 3am?

The rapid chargers all have notices on them saying they shouldn't be used during thunderstorms.

I've just checked the owners manual (albeit the US 2013 manual) and there are no warnings in there about thunderstorms.
 

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That's a sensible precaution. If a house gets struck it could travel down the charging cable to the car. If the car gets struck it could travel back up the cable to the house.

Lighting voltages are high enough to render tyres ineffective as insulators, and so the car could conceivably be the route to earth.

If the car is unplugged, lightning striking it perhaps shouldn't affect the battery as the body acts as the Faraday Cage and it is better insulated from the HV circuit, but I'm not familiar with the insulation specs.

There is considerable risk in holding a charging cable, connected to earth, in a lightning storm, but this is no different to leaning against a lightning conductor on a church wall - something I would expect to be an obvious no-no to most people.
 

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I thought about this at 3 am this morning when the storm was brewing although 1, the charge timer effectively means the car is still isolated from the mains, 2, me thinks if the house it hit the shortest path would be to ground and not through the car and tyres, 3, if the car is hit again the shortest path is to ground, 4, is my house got hit by lighting I would have a little more on my plate, 5, a claim to warranty or insurance should handle all the eventualities!
 

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Discussion Starter #5
Isn't the car connected to earth through the charger?

If it is then isn't there a path to the car through the earth even if it isn't charging at the time?
 

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Isn't the car connected to earth through the charger?

If it is then isn't there a path to the car through the earth even if it isn't charging at the time?
Indeed - Earthing is constant and isn't switched like the power circuit. Earthing is important for car charging - at normal voltages the tyres do act as good insulators, and so in the event of a fault or even arcing (like was possible with early EVs if the cable was live when you applied it to the car - I learned that the hard way) you don't want to be the path to ground.
 

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We have the transformer on the back corner of our garden, a few years ago it got hit and the flash was huge. So was the bill for 2 computers, 1 sky box, 1 Linn radio Konnect, 1 imerge sound server, 1 alarm system control board
 

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Many, many years ago an old boss of mine told me the tale of one of his first jobs being to replace a transformer on a stately home/farm estate and he fluffed the return path. Next rainstorm downed an entire field of prize cattle. True story.
 

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Many, many years ago an old boss of mine told me the tale of one of his first jobs being to replace a transformer on a stately home/farm estate and he fluffed the return path. Next rainstorm downed an entire field of prize cattle. True story.
Yeah - cattle are apparently really easy to electrocute, a lot easier than humans.
 

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I'd have thought there would have been something on BeafTalk...
 

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The biggest problem I can see with charging during a lightning storm is that if there is a strike, which insurance can you claim the repairs against? House insurance? Car insurance? I can see both companies passing the buck and not wanting to pay out!
 

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A true earth is very difficult to find.

Consider a field. It has a river flowing along the edge. The weather has been dry with recent rain. Lightning strikes in the middle of the field 100 metres from the river with 100,000V. Because the surface is wet but a foot or so down the soil is dry and insulating the energy moves through the surface layer towards the river which is at, nominally 0V. Therefore each metre distance will drop the potential by 1,000V. Halfway the voltage referenced to the river will be 50,000V.

The front and back legs on a cow might be 2 meters apart so if the cow faces the strike or the river it could have a potential of 2,000V across its heart. Sideways less.
 
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