#5 FAQ - Grounding in a fusor system

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Richard Hull
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#5 FAQ - Grounding in a fusor system

Post by Richard Hull » Tue Feb 17, 2015 8:50 pm

The only ground you should consider is a "STAR" ground. I attach an image of how it is done.

You should chose a point more or less equidistant from your pumps, instruments, fusor and power supply. At this point, install a bolt on a metal frame. a standard SAE 1/4 X20 is fine. This bolt should have a fairly heavy guage wire cable going via the shortest route to your house electrical ground. (lower left in the image)

Now, all grounds of all metallic instruments, pumps, fusor, etc., in your system need to have a separate cable going to that "STAR bolt", as in the diagram attached. It is understood that many instruments and pumps have a ground in their electrical cable's plug already. This may be quite sufficient. To be sure, run a separate ground to the star bolt as noted.

Many folks use a metal cage or gather all their fusor materials on a metal cart or in a tightly confined space. In this case, a bolt placed on the metal cage or cart's metal body will be your star ground point. Good practice places all of your electronics as close together as possible. A good fusor system might have all your gear and the fusor in a volume of about 1 meter by 1 meter by 1.5 meters tall.

Normal star grounds are made with heavy wire. For a fusor, #12 gauge wire ought to suffice. You will find a crimped-on ring connector will add in the hooking of stacked ground wires o the bolt a lot easier. I personally crimp such heavy rings on the heavy and then back fill the crimp with solder using a good heavy gun type soldering iron of at least 60 watts and 63-37 rosin core electronic solder. (60-40 is fine)

Richard Hull
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fusor ground.JPG
The idea behind the STAR ground is obvious here
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.

Joshua Guertler
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Re: #5 FAQ - Grounding in a fusor system

Post by Joshua Guertler » Wed Jul 05, 2017 8:22 pm

In order to attach this to the outlet to ground the high voltage, could I take a three-pronged plug and remove the neutral and live prongs and then plug it into the outlet?

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Rich Feldman
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Re: #5 FAQ - Grounding in a fusor system

Post by Rich Feldman » Thu Jul 06, 2017 5:48 am

Sure you could, but it would be a waste of a plug. Why not use an old metal fork, with all tines but one bent out of the way?

More practically,: Outlet cover plates are secured by one or two metal screws that connect to ground. Same ground as your NEMA 5-15 plug would get, even if the outlet-mounting box inside the wall is a nonmetallic type. Terminate your ground wire with a ring lug & put that under one of the screw heads. An ordinary plug could be pulled out if someone tripped on the wire. Screw-attached ground should maintain a safe connection, even if it's more likely to bring the tripper (trippee?) crashing to the floor.

What are you planning to do about the ground pins on power cords for your vacuum pumps and HV PS?

Joshua, you don't seem to have made the obligatory post to our "please introduce yourself" forum. It's one of the commitments stated on the registration page. Without it, readers have to guess about you. So far, it looks like you should learn more about electricity, before asking for help here about fusor electricity.
Richard Feldman

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Richard Hull
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Re: #5 FAQ - Grounding in a fusor system

Post by Richard Hull » Thu Jul 06, 2017 4:53 pm

One should choose any large, metal framed instrument chassis that has a good solid 3 prong plug whose ground is attached to the body of its chassis and bore and tap a 1/4X20 hole in the chasiss. A two inch long bolt can be secured to the chassis as a star point. All other non-grounded items, specifically all electronic instruments, power supplies, metallic vacuum system plumbing and the fusor can be manully grounded to this point via a heavy gauge wire with spade or ring lug attached attached to each item.

Make sure that the area round the bolt hole is first sanded free of paint, grease, etc. A star washer will also help make good contact with the metal chassis and the bolt. Really long gounding wires should be avoided. (Put most items as close to each other and the grounding lug as is practical in your system's mechanical layout design)

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.

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