[RE-wrenches] Lightning Damage - Need Replacements (Correction)

[Larry Crutcher, Starlight Solar Power Systems]

Hi Dan,

You mentioned that “his grounds didn't work”. Actually, they worked, just in an undesirable way. One thing to look at is how or whether the house ground system was bonded to the tower ground. If they were not properly bonded, and with poor soil condition, the potential difference between the two grounds could create very high voltages. The voltage path would be the turbine wiring to find the house ground, traveling through any AC connected items to do so.

I would like to hear more about this as it’s a personal subject of study for me.

Larry Crutcher


On Jun 15, 2014, at 4:29 PM, Exeltech <exeltech at yahoo.com> wrote:

Hello Chris,

….The system is off-grid north of Fort Worth, Texas.  The house and equipment are sitting on and in the worst caliche I've ever seen.  It's as close to concrete as you can get.  There's virtually no topsoil.  Watering grounds won't help .. even poured into a hole.  It just sits there.  They had to jackhammer to dig the tower hole.

He's got a 110' tower for his Bergey.  He told me they drove numerous grounds diagonally into the bottom of the tower hole from the edges, bonded them all together, then connected everything to the tower, as well as the other equipment using #4 AWG solid.  All of the guy wires are equally bonded.  Lightning hit the tower directly, but the fact is .. his grounds didn't work.  Everything electrical in the house was destroyed.  Didn't matter if it was turned on or off.

The only things that DID survive are his batteries (as far as he can tell) .. and the Bergey itself.  He connected a three-phase diode array directly to the Bergey output leads, and it's charging his batteries, just not as well as with the controller in place (of course).  The genny runs smoothly in the wind, meaning all three phases are intact.  If one or two phases were open, you'd see it and hear it in the motion of the blades - much the same effect on the engine if you had a plug wire fall off.  If you're a wind person (how can you NOT be in Montana?) .. you already knew that.

He may bonded everything to his well casing.  I don't know - but I'll ask.  This is indeed a good learning opportunity.


I'm going to help him get things operating again .. and will highly recommend some of the new lightning protection units Midnite is making.

In the meantime .. charge controllers and inverters first.


Thanks!


Dan