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Electrical surge/lightning strike - what insurance would cover?

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andrewket

Well-Known Member
Dec 20, 2012
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Just had an interesting thought as I gaze outside my office window at the rain and lightning here in NoVA (DC) this evening. If a Tesla is plugged in and there is a surge that causes electrical damage to the car, what insurance, if any, would cover this?

Auto?
Home owners?

Andrew
 
I asked my company (State Farm), and was told that my most homeowner's insurance policies will not cover any motor vehicles, and that comprehensive coverage on your auto policy would be responsible.

Presumably, if only your UMC were destroyed, your homeowner's insurance might replace it as an electrical appliance that is not considered a motor vehicle.
 
I'm presuming it would be with a bunch of other appliances that have fried as well.
A direct lightning strike to utility wires far down the street is a direct strike incoming to every household appliance. Are all damaged? Of course not. Because damage means another outgoing path must exist. Damaged are selective appliances (or Tesla) that also make that outgoing connection to earth.
 
A direct lightning strike to utility wires far down the street is a direct strike incoming to every household appliance. Are all damaged? Of course not. Because damage means another outgoing path must exist. Damaged are selective appliances (or Tesla) that also make that outgoing connection to earth.

As most major metal appliances (range, oven, microwave, washer, dryer, computer, etc., etc.) have a ground connection via the equipment grounding conductor, there is plenty of a return path to ground through these devices when we're talking about the voltage that lightning brings. In addition, the voltage that lightning brings can easily jump switch gaps to return to ground via the neutral conductor on 120V loads because of the extremely high voltage (or even 240V to reach 120V neutrals on the other leg). Lightning is very unpredictable and in my experience, I simply couldn't predict and surely wouldn't bet upon which appliances would be destroyed and which ones wouldn't, even armed with information about their grounding.
 
Lightning is very unpredictable and in my experience,
Lightning is unpredicable if, for example, you assume all grounds are same. The phrase was very specific. Earth ground. If any appliance is earth grounded, then it is the perfect path for a destructive surge. But appliances are not earthed grounded. Appliances connect to a completely different ground - the safety ground (code calls it equipment ground).

A house has many and different grounds: motherboard ground, chassis ground, floating ground, analog ground, etc. Some are interconnected. Others are not. And yet every one is electrically different. And then it is even more complex. Materials assumed to be insulators (ie concrete, some wall paints, linoleum tile, wood) are actually electrical conductors.

The incoming path is obvious. But what is the outgoing path to earth? Even wire length and wire splices affect that answer. Damaged are appliances that make a best connection to earth ground. Removing a safety ground from any appliance does not change protection or risk to that appliance. Addressing the earth ground does.

Properly noted is that millimeters inside a switch, fuse, circuit breaker, etc do not seriously impede a surge. Because surges are not voltage sources. Destructive surges are current sources. That means voltage increases as necessary to blow throught anything that might stop it.

How to protect a Tesla? What is the path to earth? Is that path destructively via any appliance or Tesla? Anyplace that question is answered means even direct lightning strikes without damage. But again, earth ground is electrically different from a safety ground connected to appliances. Not knowing that is but one reason why lightning is confusing or mysterious.
 
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Lightning is unpredicable if, for example, you assume all grounds are same. The phrase was very specific. Earth ground. If any appliance is earth grounded, then it is the perfect path for a destructive surge. But appliances are not earthed grounded. Appliances connect to a completely different ground - the safety ground (code calls it equipment ground).

The house is full of ground: motherboard ground, chassis ground, floating ground, analog ground, etc. Some are interconnected. Others are not. And yet every one is electrically different.

The incoming path is obvious. But what is the outgoing path to earth? Even wire length and wire splices affect that answer. Damaged are appliances that make a best connection to earth ground. Removing the safety ground from any appliance does not change protection or risk to that appliance. Addressing the earth ground does.

Properly noted is that millimeters inside a switch, fuse, circuit breaker, etc do not seriously impede a surge. Because surges are not voltage sources. Destructive surges are current sources. That means voltage increases as necessary to blow throught anything that might stop it.

How to protect a Tesla? What is the path to earth? Is that path destructively via any appliance or Tesla? Anyplace that question is answered means even direct lightning strikes without damage. But again, earth ground is electrically different from a safety ground connected to appliances. Not knowing that is but one reason why lightning is confusing or mysterious.

All very accurate. We can also purchase a lightning arrestor that will be connected externally or in your main electrical box.
I am not familiar with the whole problem, but I have installed them in all my residences and offices. If I remember correctly, the surge the arrestor would clamp would be app. 300,000 to 600,000 AMPS depending on your budget. The cost is not very much,
considering I was protecting my home from meltdown. Also if I recollect, the clamping rate is also very quick, somewhere around
3-5 milliseconds.
 
If I remember correctly, the surge the arrestor would clamp would be app. 300,000 to 600,000 AMPS depending on your budget.
An 'arrestor' does not do protection. The 'arrestor' should have less attention. Some incoming wires (ie cable TV, satellite dish) have best protection with no protector. In every case, protection is what every incoming wire connects to: single point earth ground. Either via a wire or via a protector.

Protector is simple science. Protection is defined by an art (what absorbs hundreds of thousands of joules): earth ground. A protector is only a connecting device to earth. It exists only when an incoming wire cannot connect direct to earth. In every case, protection is defined by the quality of and connection to single point earth ground.

A surge that is earthed BEFORE entering a building will not hunt for earth destructively via the Tesla.

A 'whole house' protector (ie Cutler-Hammer) even sold in Home Depot and Lowes for less than $50. The art of protection is single point earth ground and a low impedance (ie 'less than 10 foot') connection to that electrode. That 'whole house' protector features the short and dedicated wire to earth. Protection is always about the path to earth - destructively or harmlessly.
 
I am extensively familiar with the concepts that you speak of, westom.

The official NEC term for the "safety ground" (as you call it) is the "equipment grounding conductor" or EGC, not "equipment ground".
The EGC provides a low-resistance electrical path to earth ground via the grounding electrodes found at the electrical entrance to a building.
Electrical voltage supplied via conductors to an appliance can jump through the appliance's control boards via an electrical arc to the chassis, which is connected via the EGC to the earth ground for the building.

Furthermore, the neutral conductor for 120V loads provides a low-resistance electrical path to earth ground via the bonding that is accomplished at the Service Equipment.

I have seen it happen and I have indeed been the victim of several destroyed appliances.
 
Protector or the term I used "lightning arrestor" an older wording not offen used is the same. It will overcome most of the transient
electric transients caused by lightning strikes.
The question was not how to protect your cable,television,telephone that could enter from the backdoor.
The protection for your MS. simply is a ground that has been installed correctly and a lightning protection equipment.
 
Protector or the term I used "lightning arrestor" an older wording not offen used is the same. It will overcome most of the transient
electric transients caused by lightning strikes.
The question was not how to protect your cable,television,telephone that could enter from the backdoor.
The protection for your MS. simply is a ground that has been installed correctly and a lightning protection equipment.

Your best protection. You cannot guarantee that lightning will not destroy the EVSE or chargers, though -- there are still opportunities for high-voltage currents to seek ground through those devices depending upon where the lightning strike lands and where it introduces the current.

...and in that case, the relevance to the OP's question, means that your auto insurance will have to cover your Tesla.
 
Your best protection. You cannot guarantee that lightning will not destroy the EVSE or chargers, though -- there are still opportunities for high-voltage currents to seek ground through those devices depending upon where the lightning strike lands and where it introduces the current.

...and in that case, the relevance to the OP's question, means that your auto insurance will have to cover your Tesla.

That is the answer.
 
I had the exact scenario with an RV plugged into the house. Lightning put a hole in my roof and fried many things. Interestingly no TVs though. It also fried the RV taking out lights, transmission computer, ABS computer and the input relays fom the power cord. plus all the roof tile from the explosion in the roof shot into the side of the RV.
I tried to argue it being part of the house since it was plugged in because it traveled through the cord to the RV. Homeowners would not have anything to do with it. Later I found it struck the RV as well melting the aluminum awning cover.
It sucked because then I had two large deductibles to pay instead of one. Hence the name BLKCLD