Yes and Yes. All glass has naturally occurring UV inhibitors but we are not adding additional filtration as some amount of UV is known to be beneficial, the primary function of the glass lens is to aid in heat retention and evacuation (air cooled).
Clear glass does result in slightly reduced light due to the lambertian refraction effect. The amount depends on the lamp type, glass thickness, shape of reflector and reflective materials.
No, all ETL listed reflectors are tested without air flow being present. However the primary function of an air cooled is to induce air flow and evacuate the heated ambient air.
This primarily depends upon the ballast type (magnetic vs electronic) and also the lamp type (HPS vs Probe Start MH). Some magnetic ballasts can use “long range ignitors” for up to 50’, and most Electronic ballasts reliably fire lamp at lengths above 50’.
Higher voltage operation reduced the amperage consumption. However we all pay for electricity by the Watt. There is no effective power savings in operating 240v vs 120v.
Look at your local power bill for the rate per KW (kilowatt), per hour. Example if you pay .10$ per KW it will cost you .10$ to operate a 1000w system for 1 hour (note: all systems have a certain % of efficiency loss. Typical 1000w ballast / lamp actually consume approx 1080w)
Look at the extension cord ANSI rating for maximum wattage / amperage allowed. Never exceed or operate at maximum load rating of an extension cord.
Ensure fixture is not powered & lamp has been allowed sufficient time to cool. Use a clean dry cloth and gently wipe the outer jacket of the lamp.
No, some ballast may be 120v only, or 120v/240v or true Quad voltage 120v/208v/240v/277v. Depending on fixture type a licensed electrician may be required to alter the voltages. Altering voltages may potentially void ETL rating and warranty. Certain Electronic ballast are “intellivolt” and do not require internal wiring modification to operate at different voltages. Please refer to your individual product for appropriate markings and operation instruction.
Color Rendering Index is a subjective measurement of how well a lamp source renders colors. A measurement of the degree of color- shift an object undergoes when illuminated by a light source when compared to a reference source of comparable color temperature. Incandescent light is assumed to have a CRI of around 100 so it will render all colors correctly. MH only has a CRI of about 70, so only 70% of colors will be rendered correctly. HPS has a CRI of 22.
Color Temperature is not how hot the lamp is. Color temperature is the relative whiteness of a piece of tungsten steel heated to that temperature in degrees Kelvin. HPS has a warm (red) color temperature of around 2700K as compared to MH at 4200K, which has a cool (blue) color temperature.
What is important to remember about these two terms is that CRI readings, of two sources, can only be compared if their color temperature is equal. You cannot compare the CRI of HPS (CRI=22) vs. Metal Halide (CRI=70) because the color temperatures are dif erent (2200K vs. 4500K).
Lumen is a measurement of light output. It refers to the amount of light emitted by one candle that falls on one square foot of surface located at a distance of one foot from the candle. Traditionally, lumens have been the benchmark of a lamps ability to grow plants; meaning the brighter the lamp the better the plant. However, studies have shown that a broader color spectrum lamp will perform much better than a lamp with high lumen output, especially when it comes to plant growth.
Traditionally, fluorescent lighting was used for seedlings, cuttings and plants with low light-level requirements and HID was used for established plants and plants with higher light-level requirements. Advances in fluorescent lighting technology, however, have provided more options for horticulturists. T5 fluorescent lighting is the latest in plant growth lighting. T5’s high-light output combined with its low heat and energy consumption makes it an ideal light source to grow a broader array of plants.
T5 lamps provide the ideal spectrum for plant growth. Photosynthesis rates peak at 435 nm and 680 nm. A 6500K T5 lamp has a spectral distribution with relative intensity peaks at 435 nm and 615 nm. This equates to very little wasted light energy in terms of plant growth. T5 lamps promote incredible health and vigor of seedlings and cuttings. Root development is superior relative to other lighting sources. While T5 lighting is excellent for starting seeds and cuttings, it’s also able to produce enough light for full term growth. Because of their minimal heat output, T5 lamps can be placed 6” - 8” above the plant canopy which maximizes photosynthetic response. Unlike conventional fluorescent lamps, plants grown under T5 lamps do not have to be rotated to the center of the lamp. T5’s slim diameter enables better photo-optic control of the emitted light, increasing efficiency in the form of even light distribution.
Environmental Impacts of T5 (at a glance):
- T5 lamps have a diameter of 5/8” – smaller is better when it comes to manufacturing, transportation and disposal.
- Reduction in raw materials and components needed for manufacturing.
- Reduction in lamp and fixture packaging materials due to relative size.
- T5 are constructed of 40% less glass than T8.
- T5 contain 30% less phosphor than T8.
- T5 contain 3mg of mercury. 70% less than T8.
- Longer lamp life means reduced maintenance cost and less going to the landfill.
The higher the wattage the further away you want the light to be from your plants due to the amount of heat. HID lighting will be further away than a fluorescent fixture because of this. When mounting your lighting fixture take into account the type of plant and how tall the plant will grow. You want to keep the light as close as you can, but not so close to burn the plant. A simple rule is “if it is comfortable for the back of your hand, it will be a safe distance for your plants”. Doing a little research on the type of plant and where it comes from will help in determining how much (or little) light your plants like. With fast growing plants, you may need to check the hanging height on a regular basis as plants that get too close to the lamp will be severely burned.
Source: Hawthorne Gardening Co.