High Pressure Sodium Lamps or HPS Lamps | Electrical4U High-pressure sodium lamps (also known as HPS Lamps or HPS lights) are a type of sodium lamp that is widely used in industrial lighting and many public outdoor areas. They are commonly used in public parking lots, roadways, and other security areas. A big driver behind their use is their Sodium-vapor lamp - Wikipedia OverviewDevelopmentLow-pressure sodiumHigh-pressure sodiumEnd of lifeA sodium-vapor lamp is a gas-discharge lamp that uses sodium in an excited state to produce light at a characteristic wavelength near 589 nm. Two varieties of such lamps exist: low pressure and high pressure. Low-pressure sodium lamps are highly efficient electrical light sources, but their yellow light restricts applications to outdoor lighting, such as street lamps, where they are widely used. High-pressure sodium lamps emit a broader spectrum of light than the low-pressure lamps, but they stiSee more on enpedia · Text under CC-BY-SA license The Sodium Lamp - How it works and history The lamp turns sky blue as the xenon lights. The arc then heats up the mercury and the mercury vapor then lights, giving the lamp a bluish color. The lamp heats and the sodium is the last material to vaporize. The sodium vapor strikes an arc over 240 C. High Pressure sodium Lamp Wiring Diagram | autocardesign High Pressure sodium Lamp Wiring Diagram– wiring diagram is a simplified gratifying pictorial representation of an electrical circuit. It shows the components of the circuit as simplified shapes, and the capacity and signal connections surrounded by the devices.