Our Guide to Dimming
Dimming lights can be a great way to create the perfect atmosphere for a relaxing evening meal with friends while increasing the brightness in your space can help with focus or improve visibility on a dark winter night.
In this article, we outline some of the benefits and pitfalls of dimming, break down the most common dimming technologies, and offer some tips on how to find the right solution for your needs.
How does dimming work?
At a basic level, dimming works by controlling the current and/or voltage going to your lights. For the novices amongst us, the current is the flow of electricity, while the voltage is the pressure with which that current flows through a circuit.
An analogy often used is water in a hosepipe: the Electrical Current is the same as the flow of water through the hose, while Voltage would be the same as the pressure with which the water travels through the hose.
Reduce the amount of electricity and/or the flow, and you reduce the output - that’s the same with dimming.
The benefits of dimming
Function - The number one reason people add dimmers is the ability to adjust the amount of light in their space. Increasing the brightness of lights can be valuable for task-oriented pursuits such as working, cooking, reading or providing clear visibility. Lowering the lights can increase visual comfort, help regulate mood and set a desired ambience for a space.
Globe Lifespan - Dimming lights reduces the amount of energy that is needed to power your light globes, which in turn helps increase their life span and reduce the potential frequency of globe replacement.
Power Costs - Not only does lowering the brightness of your lights change the mood of your space, but it also reduces your energy usage. Decreasing the quantity of electricity needed for your lights generally will result in savings on your energy bill (albeit fairly small).
The pitfalls of dimming
Knowledge - The technical nature of different dimming technologies and their requirements can seem complex for those with little or no electrical experience. Please rest assured that our team is here to help!
Installation & cost - Although generally not expensive, as with any electrical work installing a dimming system and correctly hooking it up to your lights requires a qualified electrician. We always recommend getting advice from a certified electrician before you order any lighting and make sure you factor in all the associated costs. It’s also good to note here that a condition of warranty for any light fitting or dimming system is that it must be installed by a certified electrician.
Legacy Technologies - Some older households may already have legacy dimming systems in place that were designed to work with older lighting technologies (such as incandescent light bulbs). Although these legacy technologies may dim your lights, they may not offer the same level of efficiency and function as those designed for modern LED globes.
Types of dimming
Phase Dimming
Phase dimming, also known as AC (Alternate Current) dimming or TRIAC dimming, is widely used in homes and some smaller commercial settings. The electrical grid supplies alternating current (AC) electricity to our buildings. The AC electricity travels as a wave of energy, and phase-cut dimming works by cutting off certain parts of each wave.
There are two main types of phase dimmers:-
Leading edge dimming - is an older technology that works by cutting off the front of each wave (the ascending segment). It generally only offers up to 40% dimming capability and runs at a higher wattage, so it suits legacy globe technologies like halogen or incandescent bulbs.
Trailing edge dimming - works by cutting off the end of the wave (the descending segment). It is more modern than leading-edge dimming and offers up to 100% dimmability and better control, such as multi-way dimming. Most modern dimmable LED globes are compatible with trailing-edge dimming systems.
Phase dimmers are effective and affordable for your home, they can be used to dim most dimmable LED light sources when coupled to a mains dimmer switch.
Note that phase dimming isn’t generally considered the most effective solution for commercial applications due to its functional and capacity limitations.
1-10V Dimming
1-10V dimming - is a popular choice, particularly in commercial settings that works by restricting the voltage that gets through to the light fixtures. This allows for smooth and consistent dimming without the capacity restrictions of phase dimming, making this a versatile choice for larger spaces with multiple fixtures. Note that 1-10V dimming doesn’t dim to be completely off, so a separate switch is required to turn off the lights.
0-10V dimming - is another similar method to 1-10V that controls the brightness of lights by restricting the voltage to fixtures, but in this case, can go all the way to turning the lights off at zero volts.
Both methods are easy to use and work well with dimmable LED lights when matched with a compatible driver. They also require a separate ‘control’ cable to run from a dimming controller to each driver.
Note 1-10V is an analogue technology, so offers limited control of individual lighting (one/off and simple dimming options) compared to digital systems such as DALI. Also, depending on the drivers in use the dimming levels may not be consistent across a circuit .
DALI Dimming
Digital Addressable Lighting Interface (DALI) is a global standard protocol and lighting control system that allows for independent digital control of each specific light fixture (or groups of fittings). Each item is individually linked to the system with a unique digital address that allows two-way communication back to the controller.
DALI has traditionally been used in commercial environments, although we are increasingly seeing DALI used in residential projects for its superior dimming, finer control, flexibility, cost-effectiveness, and simplified wiring structure.
DALI-2 is an evolution of the DALI protocol that supports a greater number of connections, stronger support for remote control devices and improves device inter-compatibility (an downside of DALI-1), meaning consistent dimming regardless of the brands of drivers or lights.
DALI is generally compatible with most dimmable LED light sources, however may require a specific DALI-compatible driver and/or actuator to work correctly. DALI also requires a control cable that links up to all the drivers/actuators on a circuit.
Note that DALI often requires dedicated know-how to both set up and maintain the system over time.
Other options
Other dimming options available include KNX (a building automation system that can be used for lighting control), DMX (mainly used for theatrical, stadium and architectural lighting) and DSI (a simpler digital protocol similar to DALI).
In addition to this are newer systems like Casambi, which provides the ability to interact with most of the above technologies and bluetooth remote control your lights via any digital device (like your smartphone).
Frequently asked questions about dimming
What dimming technology do I need for my lights?
It depends on your project. A DALI system may be overkill for a small residential project, while a leading-edge system wouldn't be recommended for a large commercial project — the right technology depends on the scale and requirements of your specific situation.
Do all light fittings work with every dimming system?
No. Not every light fitting or globe works with every dimming system — some aren't dimmable at all, while others are designed to work only with specific dimming systems. This is outlined in each product's specifications, or you can reach out to the team if you're unsure.
Do I need a separate driver for dimming?
It depends on your light source and dimming system. Mains voltage LED sources can be phase dimmed without a driver via a dimmable wall switch, but low-voltage LED sources need a driver regardless of dimming. Non-phase systems like 10V or DALI will always require a driver (and an actuator, in DALI's case).
How do I know what capacity my dimming system needs?
As a rough rule of thumb, the combined wattage of all light sources on a circuit determines how much power your dimming system needs to handle. The power rating of the dimming hardware should always comfortably exceed the total wattage of the connected lights.
What control options are available for dimming?
The most popular option in Australia is a rotary dimmer, where you turn a dial to adjust brightness. Other physical options include slide and rocker selector dimmers, and smart dimmer switches. You can also control lighting digitally via a smartphone or tablet.
It is important to check that the fittings you are interested in and their lighting sources (whether that be globes or integrated LEDs) are compatible with the dimming technology you wish to use. Drivers may need to be purchased separately from your lighting, so please check out product specifications for more details of what is (or is not) included.
Final word
We always recommend that you discuss your lighting needs (including dimming) with a certified electrician before making a purchase. Please thoroughly check our product specifications to make sure you have taken into account all the factors that go into selecting the right fitting, this includes understanding the voltage of the fitting, the wattage of the light source(s) and dimming compatibility.
More questions? CONTACT OUR TEAM