FAQ

Who is Rand Tech?

Rand Technologies, Inc. manufactures an extensive line of high-quality interior and exterior LED lamps and fixtures that produce immediate energy savings and a rapid return on investment. We offer an extensive lighting product line backed by warranties of up to 10 years to meet the most commercial, industrial, or residential installation and retrofit needs.

For more information, please visit randt.sa

How can I compare LED lighting products?

When comparing products using specification sheets, be sure you understand the terms the manufacturer is using to describe their product’s performance. Also, understand the testing conditions under which that product’s performance data was collected. There are many ways to measure performance and just as many ways to describe it.

How can I verify the specs?

Evaluate different products by performing a field evaluation within your space or a similar sample space. Consult a lighting design expert to determine how much product to sample and the best way to go about conducting a field evaluation. Also, look for case studies and completed installations available for visiting.

 

What is Color Temperature?

Correlated color temperature (CCT) describes the color of the light coming from the LED. When comparing lighting products one to another, be sure to look at the same color temperature. Terms such as “warm white”, “cool white”, and “day white” are somewhat subjective and may differ from manufacturer to manufacturer. Instead, look for color temperature in terms of Kelvin (K), which is a more absolute way of describing CCT. This is important because LEDs with different CCTs will perform differently and may not provide a true “apples to apples” comparison. For example, a 2700K (warm white) LED is typically less energy efficient than a 5000K (bright white) LED.

 

How Lighting Color Temperature Measurement Beginnings?

"White light" is commonly described by its color temperature. Measuring the hue of “white” light started in the late 1800s when the British physicist William Kelvin heated a block of carbon. The block of carbon changed color as it heated up, going from a dim red, through various shades of yellow, all the way up to a bright bluish-white at its highest temperature. The measurement scale for color temperatures, which was named after Kelvin as a result of his work, was based on Centigrade degrees. However, since the Kelvin scale starts at “absolute zero”, which is ‐273°C, you can get the equivalent Centigrade temperature (compared to the visible colors of a heated black body) by subtracting 273 from the Kelvin color temperature.

 

What is Color Temperature Scale Application?

The term used in general illumination is the correlated color temperature (CCT). CCT relates to the color of light produced by a light source and uses the Kelvin temperature measurement scale (SI unit of absolute temperature). It describes the relative color appearance of a   white light source, indicating whether it appears more yellow/gold (“warm”) or blue (“cool”), in terms of the range of available shades of white. Many people are now familiar with the idea of a "warm" white or a “cool” white being offered by fluorescent and other light bulbs. These bulbs have vastly different color temperatures. The "warm" bulb often has a color temperature of 3,000K and casts a more orange/red light on objects. Because you normally associate warmth with red or orange objects, this accounts for the "warm" descriptive name, even though it is a cooler (lower) temperature on the Kelvin scale. A "cool" white bulb commonly has a color temperature of 4,100K and higher on the Kelvin scale.  This is in the low range of blue color, similar to ice, therefore earning the "cool" description.

 

What is Color Temperature Measurement basics?

Today, color temperature can be measured simply using a handheld meter, such as a Sekonic C-500R meter (shown in the figure) where reading can be taken in seconds with the press of a button. When the button is pressed, readings are taken from a group of sensors (blue, green, and one of two red light sensors behind the shield) and processed through algorithms to produce a Kelvin temperature reading that can be used for photography, and verification, or simply reference purposes.

It must be noted that when using a handheld meter such as a Sekonic C-500R, it must be held close to the light source or in the most neutral (average color, such as in the center of a room or space) in order to get an accurate reading of the color temperature of the light source and not the surrounding environment. For instance, if the light is held close to a red wall, the red reflection from the wall will skew the reading to the red end of the scale. Likewise, if held next to a white object or wall, the reading will be skewed higher. These skewed readings are illustrated in the Skewed Color Readings figure at the right.

 

How is Conventional Lighting Wastes Light?

In a conventional HID shoebox light fixture, for example, a large glass lamp with a gas discharge produces a large total lumen output in all directions (omnidirectional). The light must then be controlled and reflected within the fixture housing in order to deliver it to the intended task area. The larger the lamp, the less efficient the reflector is when redirecting the light because the light is emitted over a broader surface area and more light must reflect back through the lamp. This introduces significant losses and yields less useful light. About 40% of the light from a conventional fixture is lost in this way. Additionally, reflectors in conventional fixtures will collect dust and other particles over time, further decreasing their efficacy.

 

How is the LED Lighting Focuses Light on the Task?

LED lighting is directional, in which all of the light is emitted in one general direction instead of in all directions. Most LED chips also utilize beam-shaping optics to further control light distribution. Because LEDs direct all of the generated lumens in the desired direction and in an intended pattern, LED solutions to deliver the same or better footcandle readings at the target area, even with significantly less total output. This inherent benefit of LED lighting helps to enhance security, especially in parking lots and along roadways.

Moreover, lumen depreciation is substantially less over time with LED lighting than with other conventional technologies such as fluorescent or HID. Metal halide, for example, can experience up to 35% lumen degradation within the first 18 months. Facilities personnel are all too familiar with this fact, and oftentimes will plan for re-lamping and re-ballasting fixtures every two years or so to maintain proper lighting levels. LED lighting, with its significantly longer rated life, will typically take over ten years to experience a 30% reduction in lumen output in a typical exterior application (based on an L70 rating of 50,000 hours and usage of 12 hours per day).

 

What is Operational Cost Savings?

Beyond these construction cost factors, the total ownership of operating solid-state lighting systems is much lower than any traditional technology when the following costs are considered:

•     Energy consumption: Minimum of 55% reduction over other technologies

•     Replacement lamps: Life ratings are 5-20x longer than conventional lighting

•     Replacement ballasts: Most LED fixtures and lamps have integral drivers that don’t require field servicing

•     Maintenance labor: Long life results in nearly zero maintenance labor costs for years

•     Maintenance equipment: Unplanned high-access equipment needs for lighting systems are virtually eliminated

•     Maintenance risk: Near-zero maintenance work at heights, reduces or eliminates fall risk

•     Overhead costs of facility operations: Communication of maintenance needed, service requests, work orders, maintenance contracts, insurance risks, material ordering, and lighting material storage areas are practically eliminated

•     Production loss: Downtime for lighting maintenance is virtually eliminated

•     Production loss: Downtime due to re-strike cycles in power spikes, outages, and generator transfer events are eliminated due to the “instant-on” attribute of solid-state lighting

•     Increased maintenance with control systems: Conventional lamp and ballast lives are greatly reduced with increased on/off cycles when used with control systems. On/off cycles have no degrading effect on solid-state lighting systems.

While the higher initial cost of LED lighting systems may give the impression that the technology is too expensive, the reality is that LED lighting offers a true “value-engineered” solution for modern building practices. When calculated from a global perspective, the savings in infrastructure construction costs and the resulting leaner operating profile of the building prove that LED lighting is the right choice. Modern design-build and construction professionals who embrace solid-state lighting set themselves apart as the most forward-thinking members of the construction community. Projects that incorporate this technology yield tremendous long-term benefits to building owners. When the “total cost of ownership” is calculated for any project, LED lighting proves out as true “value- engineering”.