Architects or interior designers will provide a reverse ceiling plan showing where the lights should be located on a project. Symbols for lights are typically circles. Sometimes wall/floor receptacles are included, if lamps will be used in the room.
Group the lights by room and create a scope of work. If motorized drapery is involved, include in the scope of work by room. Scopes of work are necessary to organize the project and also a way to communicate to the owner and the electrician. Most rooms have obvious borders, like walls, but staircases will extend at least three floors. A staircase should be considered as one room. Same as hallways, on any specific floor, all lighting in the hallway should be grouped together.
Each group of lights is made up of zones and are switched off and on together. If it can be avoided, do not mix different types of light fixtures in any one zone. Only consider a room for lighting control if it has more than three zones. Lighting in the interior of a project should be dimmable and lighting zones in the exterior should be on/off control. Fireplaces are an on/off application. Motorized drapery should also be grouped together, with blinds over glass doors isolated for independent control.
Strategically place keypads at all entries and exits to a room. For most rooms there will be a requirement for one keypad, maybe two. But, staircases and hallways may have up to three or four keypads. Determine how many buttons will be required at each location. If lighting is only being controlled, then a five-button keypad will do. If lighting and drapery are being controlled, consider a ten-button keypad. Each keypad should allow for preset scenes, raising or lowering light levels or drapery and an all off switch for the room only. Keypads located at the entrance to the building or keypads in the master bedroom should allow for more functionality, like exterior lighting or whole house on/off control.
Dimming panels should be located very close to the rooms they control. Try to avoid one central location for all the dimming panels, because the wiring will get congested, unruly and very costly. Also, dimming panels should be assigned to each room, because a distributed control system is more reliable than an all-in-one control system. Each dimming panel should be self contained, meaning it should be programmable and have independent control buttons built in. If something happens to the control network, like a keypad failure, these dimming panels will maintain control of the lights in their respective room.
The programmable logic controller (PLC) should be located near the power distribution panel. When service is necessary, an electrician will go to the power distribution panel to check breakers to determine where the fault may be. He will also be able to check the PLC to help trouble shoot the problem. All exterior and landscape lighting should be run to this location so that switching of these circuits can be done by the PLC.
Create a wiring diagram showing the interconnection of all keypads and dimming panels. Labels for all keypads and dimming panels are important. When the electrician is doing the wiring, he should label each wire with its unique identification, so if trouble shooting is necessary in the future the problem can be resolved quickly. Number labels are better than word labels because the label will have the same length.
Each room will have its unique number so that the dimming panels and keypads will be easily recognized as being associated with each other. All wiring on the drawing should show number of conductors and size of wire. The electrician will be able to determine the quantity and type of wire required for the project. When the wiring is complete and done according to the wiring diagram, the wiring diagram becomes a create tool in tracing wires when all the walls are closed in and finished.
A good lighting design at the beginning of a project will guarantee a reliable electrical system and a user friendly control system for the customer.