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26
May
2021
Dimming – What you need to know
LEARN ABOUT PHASE CUT, 1-10V, DALI AND CASAMBI DIMMING OPTIONS…
PHASE CUT
Modulating the input signal to reduce the power to the load by ‘chopping’ the signal. This is the most common and cost-effective method.
Many dimmers on the market combine leading and trailing edge and are known as universal dimmers, allowing leading and trailing edge to be interchangable. Trailing edge generally performs better with LED due to the nature of LED drivers.
Pros: a) Least expensive, b) Uses wall dimmers
Cons: a) Less dimming range than other options, b) LED dimming is a relatively new concept so some luminaires have no phase dimming LED drivers available. Must ensure the dimmer is compatible with the driver.
1-10V DIMMING
Utilizes an extra 10v signal (generated by the LED driver) which is cut by the dimmer down to 10% of the driver load.
This dimming protocol is generally used with control systems but analgoue wall dimmers are available. Dimming is controlled by an external driver wired to 2 additional low voltage cables connected to the wall dimmer.
Pros: a) As it is an analogue system there are no comptibility issues between drivers and dimmer, b) consistent dimming range compared to phase dimming, less expensive than DALI.
Cons: a) More expensive than phase cut, b) Important to match the driver load within 70% of the luminaure output, c) Only used on luminaires where the driver is external, d) pre-planning during installation is critical to ensure power cables have been laid prior to installation.
DALI – DIGITAL ADDRESSABLE LIGHTING INTERFACE
DALI is a dynamic dimming system that provides two-way digital communica- tion between individual LED drivers and the control interface. Each LED
Dali-driver has a unique programmable address providing a wide range of dimming possibilites ie. grouping luminares to create dimming zones, creating a circadian effect throughout the day to complement daylight levels. Dali also allows for integration of various other controls such as movement sensors, daylight sensors, timers etc.
Pros: a) Flexibility for control of individual or grouped luminaires b) allow-
ance to add many different controls, c) More precise light level control than phase cut dimming, d) Consistent dimming as it is a standardised system that can manage different LED driver brands
Cons: a) DALI Drivers tend to be more expensive than Phase Cut or 1-10v
dimmable drivers, b) Cost of control system, c) Additional cost of commission- ing the system, d) Cannot be added retrospectively as it requires wiring during installation
CASAMBI
Casambi is a a state of the art bluetooth system allowing control over luminaires through a wireless mesh nework. The system is replicated in every node creating a system with no single points of failure. Control over the system is through the Casambi App which works with both iOS and Android devices, is easy to use and free to download by the end-user.
Pros: a) Flexibility for control of individual or grouped luminaires, b) allowance to add many different controls, c) More precise light level control, d) Can be added retrospectively, e) Controlled through the Casambi App, f) Innovative technology
Cons: a) More expensive than Phase or 1-10v dimmable drivers, b) Additional cost of commissioning the system if required
