[Elecraft] OT Power Strip suggestion.

Jim Brown jim at audiosystemsgroup.com
Wed Feb 21 03:41:54 EST 2018


Unfortunately, the most commonly "thought to be the best" surge 
protectors often CAUSE destructive equipment failure.  These devices use 
MOVs to conduct the surge to the Green wire, and that ANY surge 
protector that does that raises the voltage on the chassis of the 
equipment to a VERY high level. When that equipment is connected to 
equipment plugged into a different outlet, the DIFFERENCE in potential 
between the two pieces of gear is very likely to fry circuitry in both 
of them.

The ONLY safe place for MOV protection is at the service entrance -- the 
"whole house protector."  The only safe protection on a branch circuit 
(that is, anywhere else) is a SERIES MODE protector. Series-mode 
protectors store the surge in a big inductor, then slowly discharge them 
after the surge has ended. They are widely used in pro audio systems, 
which have many interconnections between equipment. That industry uses 
protectors made by Surge-X; a company called Brick Wall is a competitor 
that focuses on the home entertainment market. I use Surge-X units in by 
home, office, and ham station.

I've done consulting work and technical writing for Surge-X, but I was 
specifying their products for the large audio systems I designed at 
least ten years before they hired me for technical writing and teaching 
at industry trade shows. In other words, my recommendations are 
professional, not based on a business relationship, and I haven't done 
anything for them for about four years.

There are more detailed tutorials about this on my website.
I wrote http://k9yc.com/SurgeXPowerGround.pdf

The next two links are for a 4-hour tutorial workshop that Andy Benton 
and I taught at Infocomm for 6-8 years.

Andy and I collaborated on
http://k9yc.com/InfoComm-PowerSystems2012.pdf
and the material on surge protection is Andy's work.  There's nothing in 
it that I disagree with.

This one is all mine. http://k9yc.com/InfoComm-Grounding2012.pdf

This slide deck focuses on our ham stations. It served as much of the 
basis for N0AX's excellent ARRL book on the topic.
http://k9yc.com/GroundingAndAudio.pdf

Bottom line -- proper grounding and bonding is FAR more important than 
surge protectors. Good surge protection isn't cheap, but cheap surge 
protection is more likely to CAUSE equipment failure than to protect 
against it. If you don't want to spend the bucks, do the proper 
grounding and bonding, which is, essentially, free. The "whole house" 
units take care of strikes coming in on the power line, the branch 
circuit units take care of what's picked up on wiring within the house.

The whole house protector I'm using is made by Joslyn. I didn't do 
research to find it -- a fellow ham bought some at a good price and 
offered them to me. It's a high quality unit.

73, Jim K9YC

On 2/20/2018 11:15 PM, hawley, charles j jr wrote:
> These were always thought to be the best.
>
> https://www.tripplite.com/isobar-8-outlet-surge-protector-12-ft-cord-3840-joules~ISOBAR8ULTRA



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