Pearson 365 and 367

Pearson 365 and 367 => Pearson General Non-Mechanical System Maintenance and Repair => Topic started by: Dale Tanski on February 26, 2015, 03:03:40 PM

Title: Lightning
Post by: Dale Tanski on February 26, 2015, 03:03:40 PM
Pete mentioned lightning and within 15 minutes I stumbled upon this article that I thought was very worth reading. 
Enjoy...
http://www.boatus.com/seaworthy/magazine/2015/january/lightning-facts.asp (http://www.boatus.com/seaworthy/magazine/2015/january/lightning-facts.asp)

Dale
Title: Re: Lightning
Post by: PeteW on February 27, 2015, 06:56:16 PM
My old boat was a Dufour and was a simple boat. But had what I thought was a very smart bonding system. They did not connect the standing rigging to anything below the waterline directly. But there was a Gas Discharge Tube connecting the standing rigging to the keel bolts. Based on the splattered metal inside I'd say it had discharged more than once.

Here is such a device from Littlefuse.

http://www.littelfuse.com/~/media/electronics/datasheets/gas_discharge_tubes/littelfuse_gdt_sl1026_datasheet.pdf.pdf

For those who are contemplating something other than a direct connection to things below the waterline this product might have some advantages in that it does not promote electrolysis but will pass thousands of amps if the breakdown voltage is ever exceeded. Static electricity, lightning, hitting a high tension wire. Its an open circuit the rest of the time.

To discourage lightning strikes on the mast, I envision putting one of these in between the standing rigging part of the bonding system and the other half of the bonding system for through hulls and the strut. Everything except the motor, vdrive which is already connected to DC ground. My main concern is that 200 V breakdown is too high. I'd want a device that triggers on 100 volts or less. They make them but not with the fuse holder model.

Its a three terminal device so it might go:     rigging----> <----DC ground
                                                                                 ^
                                                                                  |
                                                                           Bonding System

I need to see what the ABYC says about these.

Pete


Title: Re: Lightning
Post by: SVJourney on February 27, 2015, 07:14:15 PM
Nice to see that Beth Leonard is still writing.  She is one of our inspirations to do this lifestyle when we read the Voyagers Guide to Cruising.