Lighting Maintenance: Metal Halide and LED Systems
What is Lighting Maintenance?
Lighting maintenance is the upkeep, replacement, and updating of a lighting system.
Lighting maintenance is just like maintaining your car. Even though you manage to get your car to start up and get you from point A to B, that doesn’t always mean a very healthy car! We’ve all been there, maybe skipping an oil change, not replacing needed parts, and making a bad habit of ignoring weird sounds! It comes back to haunt you in the end because we are likely spending more money per gallon of gas because of the inefficiency we’ve created. Not to mention shortening the life of our vehicle.
Why is maintenance on Metal Halide systems important?
The bottom line is that a metal halide system will only operate at its’ full potential if it’s being properly maintained. Just like car maintenance, a metal halide lighting system is conceptually very similar. Without proper maintenance, the lamps may still “come on”, but the light levels that are produced at grade could be as much as 50% less than the light levels the system was originally intended to produce.
Why you, the landlord, should care…
Lower light levels result in lower tenant sales at night, and greater Landlord liabilities….and both are bad for your business model! Because of the “physics” of all HID (High Intensity Discharge) lamps (also fluorescent lamps) the amount of useable light that is produced by the lamps diminishes over time. The longer the lamp is in service, the less light it produces. So, let’s look at a general example.
On day 1, a lamp that is rated for 10,000 hours will produce 100% of the light it is capable of producing. By the time the lamp has operated for 40% of its rated life, or 4,000 hours, the output has been reduced by anywhere from 15% (Natural White) to 50% (low wattage standard metal halide). In addition to the natural depreciation of the quality of light, other factors such a dirt accumulation on the lens of the fixture can further diminish that amount of use-able light that exits the fixture.
Looking further… Typically, the light levels shown on a lighting plan represent the levels that can be expected after the lamps have operated for 40% of their rated life…..let’s call that the “Design Day”. So, from Day 1, when the original lamps are producing 100% of their potential lumens, until the “Design Day”, the light levels on the ground should meet or exceed the levels shown on the approved lighting plan. In reality, all of those lamps will continue to operate after “design day” and will continue to consume full energy. They will continue to depreciate, resulting in light levels that no longer meet the standard that the system was designed to achieve. We have determined that in many cases, site lighting systems that utilize a “replace lamps when they fail” strategy, over time, settle into an “equilibrium” that is roughly half the level of the “Design Day”. In other words, an improperly maintained site lighting system that was designed to meet 2.0 foot-candle minimum maintained standard may only be operating at a 1.0 foot-candle minimum maintained level after “design day”. All the lights on the property will still be consuming as much energy as it did on Day 1.
What plan should I implement to maintain my Metal Halide lamps?
To ensure that the performance of the site lighting system does not fall below the levels of the “Design Day” lighting plan, operators of metal halide lighting systems need to employ a maintenance strategy call “Group Re-Lamping”.
What is Group Re-Lamping?
Group Re-Lamping is when 100% of the lamps are replaced every time the batch reaches 40% of rated life. In some cases, that might be every year or two, in other cases it might be every (4) or (5) years. The frequency is based on the rated life of the lamps which vary by wattage, technology, and the hours of operation. When the lamps are replaced, we recommend a thorough cleaning of the lens, and the reflector.
For example, a 1000w probe start lamp is rated for 12,000 hours….40% of rated life is 4,800 hours. If the lamps operate, on average, 11 hours per night {(4,000) hours per year}, Group Re-Lamping is recommended every (12) to (18) months. However, if the lamps only operate, on average, (7) hours per night, Group Re-Lamping is recommended every (2) years.
The frequency of recommended Group Re-Lampings can be reduced in several ways:
‣ If 100% a site lighting system is currently operating “dusk to dawn”, implement a (2) zone lighting control system that will extinguish the majority of the lamps after the last store closes. This may be a simple as splitting up the circuits, or it may require a netLiNK Wireless Lighting Control and Management System.
‣ Utilize “Pulse Start” technology. “Pulse Start” lamps have longer rated lives than their wattage equivalent “Probe Start” lamps, and their depreciation curve is flatter, so the depreciate more slowly.
‣ Utilize Venture Lighting Natural White lamps and ballasts; this hybrid metal halide system produces light with a higher CRI and color temperature than standard metal halide, typically resulting in comparable “see-ability” with lamps that consume (+/-) 22% less energy, and the rated life of a Natural White lamp is typically twice as long as the standard metal halide equivalent.
Proper, and competent maintenance is a necessary evil to ensure that a very expensive, and very important asset operates properly. Landlords who take this responsibility will find that their tenants will tend to be more successful, their customers will feel more safe and secure, and their liability exposure will be reduced.
What maintenance do I need to maintain on LED Lighting Systems?
The biggest difference between maintenance on a Metal Halide system versus a LED system is that there is virtually no maintenance needs for LEDs. The biggest factor in what makes outdoor lighting maintenance expensive is because you need a team equipped with necessary gear to repair and replace lights. The biggest factor that makes LEDs last so long is their independence from ballasts and strikers and their estimated life of 50,000 to 100,000 hours. Learn more about what types of lighting maintenance services WLS offers here.
Why LEDs last…
The best quote I’ve seen on this is, “The LED is only as good as the life of its components.” (Copyright MyLEDLightingGuide.com) A LED consists of four major parts; the diode (where the light emits from), the driver (electronics), the heat sink (cooling system), and the optics. All of these components are much more durable than the fragile filaments that are in traditional bulbs.
What fails first in a LED?
The electronic driver is the component that will make or break your LED lamp. When you buy cheap and poor quality LEDs you are limiting the life of the LED. Cheap parts and poor soldering of parts won’t hold up. This same concept holds true for most electronics. The heat sink is also a very important part that should be of quality. The buildup of excess heat will also shorten the life LEDs.