Massive electrical problems

spannerman

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Got called out to a Nimbus Nova 30 which was totally dead, we charged up the batteries and found there was no life in the EVC system and the Vodia wouldn't communicate with it. I sent the HCU,PCU and ECU in to Volvo for testing and they came back saying they were completely fried from a lightening strike.
Feeling this was a job that wouldn't be simple we towed the boat back to the workshop, I got the 3 new modules from Volvo and still no life, the power at the ignition switch went from 12.5v down to 0v about 5 seconds after switch on. After lengthy searching I found that the accessory relay was the problem shorting the power to earth, fitted a new relay and the power supply was stable, but then found all 8 instruments were dead, so ordered new ones.
In the mean time all the new batteries we'd fitted died again despite being on shorepower, then that the Mastervolt charger was also a casualty of the strike, knowing I was going to be in the boat all day I thought I'd put the radio on, but that was dead too and warm, I pulled the radio/cd out and the case was too hot to touch! that's where our battery juice was going a massive internal short.
I then went through the boats systems and found the Chart plotter worked but the GPS and radar scanner were dead so have to fix those before knowing for sure the plotter has full functionality.
The bowprop control relay, the stern anchor winch control module were also dead.
We have to get the motor running before we know if the alternator is working or there is any other hidden damage.
Each time we get a bit further several new faults appear, obviously the lightening has gone through the negative circuit which is common to all equipment and toasted anything that has a circuit board.
The only things that work are the wipers and demister and pumps.
I hope his insurance covers damage by lightening strikes as the bill is going to be well over £20,000.
 
I hope his insurance covers damage by lightening strikes as the bill is going to be well over £20,000.

:(

shocking!

is there anything one can do to avoid such a mess???
Can you fit a lightning rod on a boat? and wire it straight to a separate massive anode somehow?

cheers

V.
 
Got called out to a Nimbus Nova 30 which was totally dead, we charged up the batteries and found there was no life in the EVC system and the Vodia wouldn't communicate with it. I sent the HCU,PCU and ECU in to Volvo for testing and they came back saying they were completely fried from a lightening strike.
Feeling this was a job that wouldn't be simple we towed the boat back to the workshop, I got the 3 new modules from Volvo and still no life, the power at the ignition switch went from 12.5v down to 0v about 5 seconds after switch on. After lengthy searching I found that the accessory relay was the problem shorting the power to earth, fitted a new relay and the power supply was stable, but then found all 8 instruments were dead, so ordered new ones.
In the mean time all the new batteries we'd fitted died again despite being on shorepower, then that the Mastervolt charger was also a casualty of the strike, knowing I was going to be in the boat all day I thought I'd put the radio on, but that was dead too and warm, I pulled the radio/cd out and the case was too hot to touch! that's where our battery juice was going a massive internal short.
I then went through the boats systems and found the Chart plotter worked but the GPS and radar scanner were dead so have to fix those before knowing for sure the plotter has full functionality.
The bowprop control relay, the stern anchor winch control module were also dead.
We have to get the motor running before we know if the alternator is working or there is any other hidden damage.
Each time we get a bit further several new faults appear, obviously the lightening has gone through the negative circuit which is common to all equipment and toasted anything that has a circuit board.
The only things that work are the wipers and demister and pumps.
I hope his insurance covers damage by lightening strikes as the bill is going to be well over £20,000.


One thing that springs to mind.

I'm not a fan of French built motor cruisers, more relating to engine installation and how bad some items are to get at for service. One thing that may help the prestige 32 and 36 models I work on is the fact they have both positive and negative battery cut off switches which could save them from the problems the nimbus and other british boats suffer in the event if a lightning strike.

Poor bugger, I'd say the insurer may be awkward as its classed as an act beyond normal accident and damage forces.
 
Unlucky owner, especially if moored up alongside yachts with masts as you would expect them to take the hit. My only real experience of lightening strikes was before I got into the small boat world whilst on an oil support ship in Equatorial Guinea. There were nightly squalls and we got struck two or three times a week. Main power systems were fine but the 24v dc emergency circuits got walloped a bit. Especially VHF/GMDSS fortunately on Sailor stuff you can just change the cards. GPS took a few hits too. Worst bit about that was it melted the dome. I spent quite a bit of time aloft that trip.
I hope your customer's insurance pays out as thats what he pays for. Perhaps a way of isolating the circuits from the negative loop when not in use and fit a heavy gauge conductor (60mm2 etc) from a mast head rod direct to an earth block.
 
no experience of lightning strikes, apart from being a few metres away from a strike on a tree in Swtzerland some years ago; very loud, very bright and a stench of ozone and burning wood.

The Navman VHF on my boat has fuses on both the +ve and -ve cables. I somehow don't think they'd protect from a lightning strike though; it'd easily arc across the gap left by the melted fuse..
 
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In a previous life i used to install and maintain battery powered telemetry systems.
Went to quite a few lightning strike jobs and usually ended up having to replace everything.
Would cost 3K and that was 15 years ago!

One lightning strike job perfectly reversed the polarity of the batteries installed in the unit, very odd.
 
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