This channel-letter and cabinet-lighting system is void of physical electrical contacts.
To drive an object electrically, you need to connect it to electrical wires via metallic contacts. A lamp or a luminaire is no exception. An incandescent or a fluorescent bulb illuminates, for example, when it contacts with metal connected to the wires that deliver current, or voltage. You can switch on a flashlight without using wires, but we all know its lamp connects via a metal piece that draws current from an electrical-energy-storing battery.
Have you seen a lamp (or any other electrical device) that’s driven by electricity, sans a physical metal contact to the source?
Sure, the charging system on an electric toothbrush. An electric toothbrush stands on a charger and recharges, but doesn’t have metal contacts that touch the charger. Somehow, however, it connects to the charger and draws the electric charge required for future use. This, of course, is the planned design. Imbedded into a toothbrush casing, exposed-metal charging contacts would corrode fairly quickly, because the toothbrush is frequently exposed to liquids. How does it get charged without a metallic connection to the charger?
The answer is electromagnetic induction, a process that couples magnetic energy to electrical energy (in proximity), while in the presence of changing magnetic and electric fields. English scientist Michael Faraday discovered this phenomenon in 1831, and, later, it was titled “Faraday’s law.” It’s one of the four Maxwell equations – the physics underpinnings of electricity and magnetism. Today, electromagnetic induction is frequently used in various applications, including power generation and transmission.
Transfotec (TFT) Intl., a wholly owned subsidiary of EMD Tech-nologies (Saint-Eustache, PQ, Canada), has found an exciting application for this phenomenon – electromagnetic induction – in the lighting industry. Transfotec’s core strength is transformer technology, and its engineers have applied their knowledge of transformers, and the related field of electromagnetic induction, to create devices for lighting LED strings where the LED modules need not remain in a fixed position.
TFT calls the devices LED Contactless Modules (TFT-LCMs), and they ship with an accompanying master power supply (TFT-LMPS), becoming, TFT says, parts of the TFT LED Contactless System. “Contactless” means no connectors, soldering or crimping. Instead, a standard, 14-AWG, single-stranded wire loops (freely) through a series of LED modules; they make electrical contact via the electromagnetic energy transfer. TFT warranties the system for material and workmanship defects for three to five years (see the warranty for variances).
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