Electronic Transformers 1

Within the past year, you may have noticed that we’ve been devoting more attention in our electrical discussions toward the issue of energy efficiency. This has been a topic of discussion not only in the relatively new solid-state (LED) lighting segment, but also been among luminous tubing (neon) fabricators and installers who have quietly contributed for years to energy conservation methodology. These, and attempts by various city governments to make us more frugal in our consumption of energy, have helped raise a broader awareness on energy usage in general, and what that means in the sign industry in particular.

We have again and again, stressed how the physical lamping technologies of these energy efficient displays—i.e., LEDs, pulse-start/ceramic metal halide, neon, cold cathode, high-pressure sodium, fluorescent, etc. (everything but incandescent light bulbs)—should, whenever possible, become our light sources of choice.

However, there are other components that make up our displays that also have an important effect on the resources that we are trying to save. Besides computerized light modeling and new light directing surfaces and lenses, the power supplies that we choose can contribute greatly in this context of energy efficient lighted sign elements.

One of the first items that an energy-conscience retailer or chain will normally seem to spec out, when replacing lamps on their floor space, is a directive to include electronic ballasts. In regard to the newer fixtures, lay-in or troffer styles, the use of T-8 and T-5 energy-efficient fluorescent lamps have become quite commonplace, so it’s no wonder that the newer type ballasts are normally part of that makeup.

While fluorescent and neon electronic power supplies do exist in sign lighting, they have not been the bulk of our installed power sources. On the other hand, the LED segment of our industry seems to rest exclusively on the usage of these electronic power drivers.

There is a long history of consistent, relatively trouble-free performance of those heavy “brick bat” ferro-magnetic/core and coil transformers, which explains in part why the luminous tubing sign industry hasn’t raced to gear its thinking to the newer state-of-the-art power supplies. After all, ferro-magnetics have been driving our neon and fluorescent products for close to a century now, while electronics, in comparison, are relatively new to the scene.

Earlier neon signs (circa pre World War II) were crafted with a different thought process. Those were the days when we had pretty stringent trade guilds. Back then GTO cables were cradled on porcelain electrical grade supports. Like our old knob-and-tube methods of wiring and glass housings with ferrules—along with space—supplied these fairly trouble-free installations with a proven method of containing any stray voltage.

More recently, as enclosed malls came into vogue and remoted channel letters forced new installation issues upon our industry, the technology from the core-and-coil era was adopted to accommodate a new configuration. Unfortunately, the training and in-depth understanding from the generation of skilled tradesmen didn’t cross over completely.

This column deals primarily with electrical sign lighting and how we can use available components in a code-compliant and technically competent manner. In accordance, we’ve devoted a number of columns to describing how to install various ferromagnetic transformers (for neon systems) and ferromagnetic ballasts for different fluorescent applications. During that whole time I remember only one instance where we put the spotlight on a different energy technology and then we never really did get into how that system worked. That was the TFT (Transfotec International) Octopus system and that spotlight was only in regard to one special application. We never did really dig deeply into anything that made that system so special.

Therefore, this month, we direct our thoughts to these much-overlooked electronic power supplies. These units can drive not only LEDs, but also neon and fluorescent displays and should become a far more integral part of the sign industry.

As electronics were developed and kept changing, and as miniaturization continued to steer many of our newer everyday components, including everything from computers on down, it seemed to make sense that this newer technology would at some point evolve into the neon arena as well as other forms of discharge lighting.

I remember when the first of these electronic transformers started coming down the pike. However, as I think back, to me they seemed like toys. And, because their outer cases consisted mainly of plastics, I just couldn’t rationalize them fulfilling the rigorous commercial applications that we were creating. We had, on occasion, tried experimenting with some of them in various applications, but just couldn’t seem to get them to function properly.

These were also the days that terms such as mercury migration, and false tripping started creeping into the language.

The next encounter we had with electronics involved a detail I have brought up many times before and involved the ’93/’96 standing panel for signs within the NEC.

Yes, it was that electronic power supply salesman who expressed to that board that most of our unfortunate installation ailments could be cured if all transformers were supplied with what was to become known as Secondary Circuit Ground Fault Protection devices. It was also stated at that time that this Secondary Circuit Ground Fault Protection was being widely used by many transformer makers.

More accurately, this type of protection existed with some of the electronic power supplies and the main reason this type of protection existed wasn’t as an element for property or life safety but rather as a method of protecting the power supply itself, which could be very susceptible to burning out due to capacitance coupling.

Because of this—and other developments—our commonplace wire-wound laminated iron core transformers did develop and receive sensing devices that in essence created a safer, more protected type product. Now however, we are seeking even more from different types of power supplies and at this place in time that caveat is believed to be: energy efficiency.

Therefore, let’s start breaking out some of the issues that make these newer power supplies different from their counterparts and what those specialties are.

Ever since their appearance on the signage scene electronic power supplies have been far smaller and lighter than their ferromagnetic counterparts. In fact, with electronics we’re dealing with ounces as opposed to the 12 pounds or more, which can be the weight of the older power supplies. Many of us know what it’s like to balance a 15,000/60 ferromagnetic on one’s shoulder while climbing an extension ladder and it is not a lot of fun and games.

Also, with all that accumulation of iron, steel wire and potting compound comes a rather large generator of heat and thus energy loss, which is not only needlessly squandered but which also has to be dealt with quickly because heat is one of the greatest enemies of a core-and-coil trannie. Considering this size and weight issue now also comes far more options as to where we can place these power supplies. For a core-and-coil type component, the size and bulk, in almost all cases, would relegate these items to a remote location behind the wall where the display would be going.

However, now with electronics, we have the option of placing individual trannies, because of their size and weight, within each of our mall type letters (which average around 16˝ per most landlords). We may also want to figure out how to remote them in a traditional manner—following certain protocols which must be adhered to when installing these different animals.

This then should definitely give you a picture regarding where we are going so...

(Click here to read Part 2 of this article series.)