What is Mood Lighting?
Mood lighting is the ability to change the "mood" of a room or area primarily by using lighting. Mood lighting is often referred to as scene lighting. Similar to theatrical lighting where the lighting engineer would create different stage lighting for each scene in a play or dramatic lighting effects during a scene. We similarly in residential lighting design a lighting scene for different activities in a room or area. For example, when you are cooking you want different lights on than when you sit down to eat. To create the "Cooking" and "Dining" scene we need to be able turn on and turn off different lights independently.
To turn on and turn off lights independently we need to group them electrically so that the electricity to the group of lights is controlled. Traditionally, this is done by wiring a home's lighting using a "lighting circuit". Depending on the size of the property, the property may have one or more "lighting circuits". Let's assume, for simplicity, it has one circuit. A traditional "lighting circuit", simply, is an electrical cable emanating from the fuse board routed around the different rooms. At each room, an electrical feed from the lighting circuit is wired to a light switch which in turn is wired to the group of lights that we want to control independently. Now this may seem common sense but this is an important basis to understand. It is also important to understand the term "lighting circuit". Traditionally the term "lighting circuit" is defined as the electrical cable we just described which is routed around several rooms providing the overall electrical power. When we discuss intelligent lighting control we define a "lighting circuit" as the cable from the controlling point which in this example is the light switch. The group of lights that are controlled from the light switch is defined as one "lighting circuit". Important clarification on terminology especially if you are asking your electrical to install "lighting circuits"!
Now think to yourself, what lighting would you put in our kitchen/dining room example if you were doing the lighting design to give the homeowner mood lighting?
You may be thinking of using recessed ceiling down lights in the kitchen area, a pendant light above the dining table and perhaps some under cupboard/plinth lighting provided by the kitchen cabinet supplier. This would certainly provide you with light but would it allow mood lighting?
Well, it is a start (and probably all that is installed by house builder or traditionally electrician!) Without probably knowing it, you have defined three "lighting circuits" using our terminology. For example, the kitchen down lights would be controlled by one switch, the table pendent would controlled by another switch and the cabinet/plinth lights another switch. Now, if we want to create two mood lighting scenes; "Cooking" and "Dining" we can achieve them by turning the "Cooking" light switch on and turning the "Dining" light switch off when we are cooking and vice versa with the cabinet light switch left on for both "Cooking" and "Dinning". If we had all three sets of lights on one switch, we would only be able to have all the lights on or off and hopefully you can appreciate we wouldn't be able to create the mood lighting scenes.
We have used an on/off switch so far but our "Cooking" and "Dinning" scenes may be designed so that when we are cooking we want the kitchen lights on at 80% and the dining pendant light on but not full on, say 50% brightness, so that the dining area is not in darkness. Then when we are eating, we want the reverse. To achieve these scenes we could simply replace the on/off light switches with a rotary style dimmer. There are, however, many technical reasons we do not use this approach in mood lighting which we will discuss later in this guide. For now, let's continue but still raise one practical issue with this approach. It's going to be impossible to achieve the 80% and 50% levels each and every time.