Project Description

Crestron SolarSync: Indoor Lighting Matched with Intensity and CCT of actual Daylight

The Crestron SolarSync™ Outdoor Daylight and Color Temperature Sensor (GLS-LCCT) enable the ability to regulate indoor lighting to match the intensity and color temperature of actual daylight outdoors. A single SolarSync™ sensor installed on a building’s rooftop measures the exact correlated color temperature and luminosity of the natural daylight and reports it to a Crestron® lighting control system. Accordingly, the control system adjusts the indoor RGB lighting fixtures to simulate the effect of being outdoors. Here are some deeper insights about the interesting project we contributed to and its final appearances.

The Project

The Crestron SolarSync™ measures the true correlated color temperature (CCT) and intensity (luminosity, lux) of natural sunlight or any other lighting source. It enables indoor lighting to be regulated to match the actual natural sunlight outdoors. The sensor is IP67 rated for outdoor rooftop installation, but also suitable for indoor applications.

The new Crestron SolarSync Sensor technology measures the true color temperature and intensity of natural sunlight for recreating sunlight conditions indoors.

Sensing Natural and Artificial Light Sources

SolarSync™ sensors may also be deployed indoors to sense the light output from artificial lighting sources, allowing fixtures to be precisely adjusted to achieve a specific desired effect or to correlate lighting conditions between separate spaces. The ability to adjust both the intensity and color temperature of indoor lighting to specific values can be utilized to positively influence the circadian rhythm of nighttime workers in an office or manufacturing facility or to aid healing patients in a medical or psychiatric facility. It can also be employed to benefit the experience of patrons in a public mall, museum, casino, or theme park.

The Challenge

For the initial development of the GLS-LCCT sensor, the best shape, uniformity and light collection had to be studied. As the sensor was placed deep in the body, a smart way of light collection had to be found.

The Study

Using advanced optics design and software technologies, an extensive raytrace study have been done simulating multiple daylight moments and situations, in support of the Crestron engineering team.

The Luminous Intensity has been measured in tens of different set-up using various lens systems to determine the most effective solution.

Some tens of different setups including Fresnel lenses, convex lenses, micro-lenses, both in an optically clear surface and a milky version were simulated from different angles (90 – 40 and 0 degrees) in order to simulated the sensor performance over the daylight cycle.

The Solution

In the end, Crestron was advised to go for a milky, dome-shaped acrylic cover, enabling a 180 degr. receiving of daylight. It is embedded in a compact, IP67 rated housing, suitable for installation indoors or outdoors.

The end result: a final Crestron SolarSync sensor after moulding and assembly.

The sensor is a calibrated color temperature and intensity sensor capable of achieving exact measurements consistent with CIE 1931 2° Standard Observer color coordinates. Built-in heating elements prevent snow and ice from accumulating on the dome to ensure reliable operation year-round.

The sensor is 24 Volts DC powered and energy-efficient, requiring just 70 mW in warm weather and a maximum of 5 Watts when heating itself. Power and communications are provided via a Cresnet connection to the lighting control system.

Unique Project Features

• Measures true color temperature and intensity of any lighting source;
• Enables indoor lighting to be regulated to match actual natural sunlight outdoors;
• IP67 rated for rooftop and other outdoor installations;
• Self-heating to prevent snow and ice buildup;
• Also suitable for a variety of indoor applications;
• Reports correlated color temperature and luminosity consistent with CIE 1931;
• Lifetime-calibrated with no drift over time or temperature;
• Connects to a Crestron® lighting control system via Cresnet®;
• 24 Volts DC powered via the Cresnet bus;
• 1/2″ knockout mountable to any j-box or weatherproof enclosure.

Crestron SolarSync™ Recognitions

Meanwhile, the Crestron SolarSync™ sensor got its first recognitions, including the Architectural SSL Magazine Product Innovation Award and the LFI 2018 Award:

The first sensors have been installed at the Apple Store on 5th ave in New York City.