[Milsurplus] AC Power on Ships

[Gene Smar]

Gents:

----- Original Message ----- 
From: "Richard Brunner" <brunneraa1p at comcast.net>
To: "Milsurplus" <milsurplus at mailman.qth.net>
Sent: Monday, October 25, 2010 3:58 PM
Subject: Re: [Milsurplus] AC Power on Ships


<snip>
Cathodic protection is very
> important to pipelines, piers, building foundations, etc, anything
> metallic in contact with soil or water.
<snip>
> Richard, AA1P
>
>

When I was designing substations for my local electric utility, I had the 
job of designing a cathodic protection system for the ground grids that 
underlay several of our Korean War-vintage substations.  Apparently, when 
these facilities were constructed during that conflict, copper was in high 
demand - probably for bullet jacketing - and our utility used scrap iron for 
the earthing electrodes.  Well, thirty years later we sampled some of the 
iron by exhuming it and found it to be in terrible condition.  So rather 
than replacing it with expensive copper (and the attendant labor to 
remove/install), we decided to construct cathodic protection systems and run 
100 VDC through the ground grid thence to a bed of sacrificial anodes buried 
around the yard.  When I left in 1983, the systems were still running strong 
at 100 VDC and a hundred or so mA.

73 de
Gene Smar  AD3F