Different Ways of Starting Fluorescent Lights

Fluorescent Lighting Systems

• Fluorescent lighting systems all consist of at least one or all of the following components: the starter system, ballast and a fluorescent lamp. The starter system starts up the light, the ballast limits the electrical current and the lamp is part of the light. These lamps or lights operate by an electrical current occurring between two metal conductors that are positioned in a glass tube, which is known as arcing. That electrical current flow goes through the gases in the tube and excites the mercury gas atoms. These atoms produce photons that vibrate and create ultraviolet light. The ultraviolet light has contact with the phosphor coating on the interior of the glass and then creates a bright light. In order for the fluorescent light to operate, the electricity running to the electrical conductors or cathodes must be larger than the electrical resistance of the gas inside the lamp so the electricity can start arcing through the gas.

Pre-Heat

• Fluorescent lighting systems that require heating the gas so it can be started are referred to as pre-heat fixtures and have a device called a starter. These light systems either have an automatic starter or require a manual start. The starter is usually located in a small cylindrical metal can. Automatic starters operate by having a higher electrical resistance than a warm fluorescent lamp and possessing a lower electrical resistance than a cold fluorescent lamp. When the lamp is cold, the electricity will go through the starter. In older lamps, the operator would be required to manual start the lamp and press the "On" button and hold it for several seconds. When the button is released, the current goes through the lamp.

Instant start

• Some fluorescent lamps start up instantly with an initial voltage to the lamp that is several times larger than the lamp's typical operating voltage and the lamp's break-down resistance,

  which starts the lamp with some force. The starting voltage for this method is up to 940 volts. Even if the gas in the lamp is quite resistant, it will usually start with such a high voltage. Once the current begins running through the lamp, it will begin illuminating and the voltage will lower to the necessary operating amount.

Rapid Start

• The majority of fluorescent lighting systems with two or more lamps are referred to as rapid-start fixtures. Instead of a starter, the light's ballast maintains a low flow of electrical current flowing through the filaments during the start-up process. The ballast uses a constant low flow of current through the filaments and uses a capacitor to start the lamp by ionizing the gas. There is a short high-voltage period between the cathodes and a metal surface in the fixture. All of these things work together to lower the electrical resistance of the gas and pull more current to create a brighter light.