Related FAQs: GFCIs and Marine Aquariums, Electricity Use around Marine Systems,  Related Articles: Marine Electrical,  Grounding Probes, Marine Aquarium Light Fixtures and Canopies,  GFCIs and Marine Aquariums,  /The Aquarium Gardener Series GFIs, RCDs, Electricity, Marine Aquariums
By Bob Fenner	Fire, electrocution?

This article discusses the rational for and use of G.F.I.s (aka RCDs in Europe) in aquarium applications and offers a practical arrangement of wiring we use in our corporation.

Why G.F.I.s? Electricity is useful, indeed necessary to our trade and hobby, and dangerous! Enough to light a Christmas bulb can kill and there is much more than that associated with tanks and ponds.

There have been several excellent survey pieces on electrical shock avoidance; the 10/79 and 2/90 FAMA If I Had Only Known's by Jim Mortensen are noteworthy. See them for an introduction to the appropriate how and what of electrical use.

Brian Clark presented a brief discussion on ground fault circuit interrupters in FAMA 11/81. I am here again hammering you into considering the benefits for minor costs that these devices offer you. Our involvement in the ornamental and scientific aquatics industry affords us almost continuous examples of electrical shock, environmental disease from electrical leakage, smoke and fire damage that would have been avoided with the technology presented here. Not enough people are aware of how inexpensive and user-friendly G.F.I.s have become. Read on.

What? A G.F.I. is an electronic electron counter. It is a device that measures the amount of amperes (numbers of electrons) coming and going through a circuit, and quickly opens (breaks) the circuit if there is a small loss, like a "brown-out" or shock to you or your livestock. These units are solid state, rugged and they work! A circuit breaker alone will not necessarily "trip" open in the event of a ground fault, even in a case of gross electrocution, ground fault interrupters will.

G.F.I.s come in three general formats: 1) Breakers, 2) Duplex outlets and 3) Plug-ins.

1) Breakers mount and function in the same way as super-sensitive circuit breakers. These are useful at the house sub-panel where all potentially deadly circuits (bathroom, kitchen, outdoor, and fish-electrics) are wired through. Their downside is A) Greater expense (@ $50.00 in 1991 dollars) and B) The lack of need and problem of hunting down the source of a fault over a long run with many outlets. Even a bad wire-nutting job may produce enough electron drift to trip a G.F.I..

2) Duplex outlets (see illustration) are useful for in-line protection just as circuit-breaker types, and are considerably cheaper (@ $8-12.00). In addition they offer the advantage of providing two additional protected outlets and an emergency on/off switch via the test-reset buttons.

3) Plug-in G.F.I.s come as hard-wired outlets with their own extension cords (very useful for power tool use), and devices that push into an otherwise non-G.F.I. protected outlet. You just plug into the G.F.I.s outlets in turn. These types of G.F.I.s retail for @ $15.00 for the straight plug-ins and @ $30.00 and up for the extension cord varieties.

And now, brought to you as a courtesy of our Construction Division, Aquatic Environments and the fine folks at FAMA, is our version of how to conform with the National Electric Code, as it relates to ponds, waterfalls... and aquariums in the future. The following illustration denotes the arrangement of a service switch, G.F.I. duplex outlet, and time clock:

This arrangement allows for either hard-wiring or plugging in two service outlets and one timer option, typically a light or pump.

The service switch gives you control to the overall circuit beyond that point, the duplex outlet provides you with more electrical access, and the timer provides necessary regularity and continuity for your system. The plug must be fitted to a truly three-pronged grounded circuit or for outdoors an accessory ground.

What will all this get you? Piece of mind! Virtual immunity form disastrous electrical leaks, shocks and electrical fires. Every year I hear of these, usually attributed to a sued manufacturer or installer, and all avoidable with the proper use of G.F.I.s. I suspect that sooner or later we will find that our aquatic charges are mal-affected by electrical leakage as this is becoming more of an issue of human concern/awareness. Don't wait. Install Ground Fault Interrupters in your aquatic systems circuits now.