I came across Dr. Richard Beeson's field research site while taking a class called Plant Water Relations. I spoke with him about lightning protection at his site with all his solenoids and data collection devices going out to his field. He explained he uses a small device that is wired from any wires or controllers coming from the field. The component is called a varistor. It is similar to a fuse and is wired to a grounding strip. If a lightning bolt is nearby and there is a voltage spike traveling back from the field the voltage spike will encounter the varistor. If the voltage spike is higher than the rating on the varistor it will automatically shunt the power to the grounding strip. In a direct lightning strike it probably will not protect you. Lightning is so unpredictable. But from a nearby lightening strike and power surge it would probably do the job of protecting your equipment. For more information than you probably care to know, here is a link about varistors and their use http://en.wikipedia.org/wiki/Varistor they cost about $0.05-$0.10 each and you will need one for each wire coming back from the solenoids in your field. (The picture to the right is a varistor from the link above from wikipedia)
In order to show a better picture of what I'm talking about I've included a short video of the setup. Here's the link to click to watch the video: http://hillsborough.extension.ufl.edu/Ag/AgOrnProd/Video/LightningVideo.html
If you happen to watch this video, post a comment on what you think about this new format for learning about new things from Extension.
Shawn,
ReplyDeleteGreat info! Not sure if I would be able to use them on mine system since each valve operates from a battery opperated solenoid. I will definately look into it.