Table of Contents
Why do street lamps turn off and on?
Some sodium- or mercury-vapor street lights, near the end of their bulbs’ lives, trigger thermal sensors as they overheat. The sensor cuts off the power to the light, it cools, and then the power comes back on to light the bulb again.
Why do sodium lights turn on and off?
High Pressure Sodium Lamps Normal end-of-life is usually indicated by the lamp cycling on and off. As the lamp accumulated burning hours, its operating voltage increases, eventually becoming higher than the voltage supplied by the ballast. The lamp extinguishes and cools.
How do mercury vapor lights work?
The mercury vapor lamp works by creating an electric current to mercury vapor within a sealed glass jacket. The bulb is comprised of an inner tube, called the arc tube, and an outer jacket (or bulb). Using too small of a ballast will result in lower light output and can shorten the life of the bulb.
Why do some street lights blink?
Some street lights are controlled by photoelectric cells that allow them to turn on at dusk and off at dawn, thus saving electricity. If the ambient light level is just at the point were the photocell will react, there might be flickering as the light level changes from above to below the threshold.
What time do street lights turn off at night?
For the most part, local authorities run street lights from dusk to dawn, or sunset to sunrise. Some will switch off at night (i.e. after midnight) when people don’t need them. Some modern street lights are run based on light sensors.
How do you fix a mercury vapor light?
How to Repair Outdoor Mercury Lights
- Turn off the electricity to the outdoor light.
- Loosen the screws on the ballast cover and remove the cover.
- Remove the screws or wing-nuts that secure the ballast wiring inside the light.
- Unplug the photocell.
- Retrieve the bulb and screw it back into the fixture.
Why does my mercury vapor light go on and off?
As a lamp gets older, the maintaining voltage for the arc eventually rises to exceed the maximum voltage output by the electrical ballast. As the lamp heats to this point, the arc fails, and the lamp goes out.
How does a mercury vapor light work?
Mercury vapor lights consist of a gas-filled glass chamber, protective glass bulb, electrodes and a ballast. The ballast sends electrical power to the electrodes, which excites the gas and makes it glow. The protective bulb filters out harmful ultraviolet light and keeps the mercury gas contained if the inner chamber breaks.
Is it time to retrofit your mercury vapor lamps with LED lighting?
Today, there is a continued push to retrofit mercury vapor lamps to LED. Based on cost savings, quality, and political factors – our experts here at Action Services Group help to define why it may be time for you to retrofit your own mercury vapor lamps with LED lighting.
Do reflectors reduce the efficiency of a mercury vapor lamp?
Because you likely use a reflector to force light from your mercury vapor lamp downwards, you lose roughly 15\% of that heat. This means you reduce the efficiency of a mercury vapor lamp by 15\% simply based on the overall design of the light itself.
What is the difference between hid and mercury vapor lamps?
Furthermore, an HID light, mercury vapor lamps are omnidirectional and rely on heat to help produce lighting. Because you likely use a reflector to force light from your mercury vapor lamp downwards, you lose roughly 15\% of that heat.