HID Lighting FAQ

When do I use an HID fixture?

• HID fixtures typically do not achieve full brightness when first turned on and therefore are not suitable for all applications
• It generally takes a few minutes to for an HID fixture to reach full light output
• They should not be used with sensors
• They should not be used when full light output is required immediately upon turning on the switch
• HID fixtures should be used when efficiency and long lamp (light bulb) life is required
• HID fixtures designed for exterior applications are suitable for area lighting, security lighting, landscaping and hard to reach places where low maintenance is required
• HID lighting fixtures offer the best efficiency of any light source
• Some items to consider when choosing HID fixtures
  • What is the main function of the lighting fixture in this space?
    • Lighting tasks to consider
      • Area Lighting
      • Flood Lighting
      • Security Lighting
      • Accent Lighting
      • Task Lighting
      • Decorative Lighting
  • Consider the color of the source and how it affects the areas to be illuminated
    • Metal Halide - Bluish White light
    • High Pressure Sodium - Golden Yellow light
    • Low Pressure Sodium - Monochromatic Yellow light
  • Choose the correct fixture for the location
    • In what kind of environment will they be used?
      • Wet Location
      • Damp location
      • Dry Location
      • Vandal resistance
  • Where will the fixtures be mounted / located?
    • Pole
    • Wall
    • Ceiling
    • Ground
  • What kind fixture will you need?
    • Wattage
    • Physical size of fixture
    • Efficiency of fixture
  • What are the costs of the system?
    • Initial cost versus long term operating costs
  • Choose the most efficient system for you application based on the above factors

 HID Troubleshooting Guide

1. If the lamp will not start
   1. Check that lamp is fully inserted into the socket, do not over tighten
   2. Check that power is applied to the light fixture
   3. Check that the ballast and lamp ANSI codes match
   4. Check that the operating position of the lamp is appropriate for the light fixture used - Vertical or Horizontal or Universal position
   5. Check the condition of the lamp, try a lamp that you know works
      1. If the working lamp will not start replace the ignitor (starter)
      2. If the ignitor is part of the ballast replace the ballast.
   6. Be sure the voltage at the supply connections are within +/- 5% of the rated fixture voltage.
   7. Check that all the connections inside the fixture are secure and correct
   8. Check that the proper supply voltage is connected to the correct ballast wires
      1. Multi tap ballasts may be equipped to accept up to 5 voltages -120V, 208V, 240V, 277V and 480V
   9. Check the voltage at the socket, (open circuit voltage) and match with the information on the chart below

2. If the lamp flickers
1. Check wiring connections, they may be loose. Turn off power before opening fixture
2. Check the voltage at the socket
3. Check the supply voltage
4. Check for voltage fluctuation
3. If the lamp cycles (goes on and then goes off)
1. Check that the proper voltage is applied to the ballast
   1. Multi tap ballasts have more than one supply connection
   2. Choose the correct one for your application and cap off the others
2. Check ANSI codes of lamps and ballasts, be sure they match
   1. Verify that the lamp is correct type and wattage
3. If the lamp is HPS, the lamp is nearing its end of life
4. If the fixture is equipped with a photocell
   1. Cover the photocell with a piece of electrical tape (during the day) and wait for the fixture to turn on
   2. Check that there is no stray light coming into the view of the photocell
5. Check for drops or spikes in circuit voltage
6. For Metal Halide check lamp for proper burning position (Universal, Horizontal, Base-up or Base-down)
4. Color differences in the lamps
   1. Check wiring of ballast to socket
1. Check ANSI codes of lamps and ballasts, be sure they match
2. Older lamps tend to shift in color
   1. This is a normal aging process of lamps
   2. Group relamping reduces the effects of color differences
5. Low Light output
   1. Check ANSI codes of lamps and ballasts, be sure they match
   2. Check wiring connections, they may be loose. Turn off power before opening fixture
   3. Check for incorrect capacitor or faulty capacitor
   4. Metal halide lamps will emit low light output when nearing end of life
1. Check for blackening of the arc tube
6. Short lamp life
   1. Incompatible lamp and ballast
      1. Check ANSI codes of lamp and ballast
      2. They must match
   2. Check lamp burning position requirements
   1. Horizontal, Base-up or Base-down restrictions
   3. Check ballast for evidence of shorting
7. Slow Starting
   1. Check lamp burning position requirements
   1. Horizontal, Base-up or Base-down restrictions
   2. Check lamp ballast and ignitor for their end of life
   3. Check for drops or spike in circuit voltage

How long will the HID lamps last?

1. The Average Rated Life of HID Lamps (High Intensity Discharge) is calculated on a 50% failure rate
   1. The point at which 50% of the test lamps are operating and 50% are burned out
   2. Not all lamps will continue to operate at the rated life
   3. Some lamps will fail before the average rated life and others will continue to operate beyond their expected life.
   4. Metal Halide lamps Average Rated Life is 6,000 to 20,000 hours
   5. High Pressure Sodium lamps Average Rated life is more than 24,000 hours.
2. As lamps age and eventually fail you will see evidence of failing lamps
   1. Metal Halide lamps will take longer to start and will begin to look pink
   2. High Pressure Sodium lamps will start to cycle
      1. They will come on turn off and then restart after a few minutes.
   3. Both types of lamps will develop blackened arc tubes.