SET Chapter 18 to 20 PDF

Learning Outcomes Describe the function of the scene master of a home automation system Describe and program the scene master for complex lighting scenes (e.g., switching, dimming) Describe and program a button as a master-off scene Describe the use of remote control to access c...

Learning Outcomes Describe the function of the scene master of a home automation system Describe and program the scene master for complex lighting scenes (e.g., switching, dimming) Describe and program a button as a master-off scene Describe the use of remote control to access complex scenes 2.7.1 Function of Scene Master of a Home Automation system The scene master is a display panel, usually programmed on a master device, for a user to monitor and control all the lighting (if not all the electrical loads) within the home or building. Ideally, this device should be placed in a central location so that people can access it conveniently. A typical scene control is the master on/off control, which one can use to turn on and off all the lighting by pressing the master-on and master-off button. Unit 2.7 | Scene Control 120  2.7.2 Scene Master Incorporating Switching and Dimming There are many possibilities for setting scenes. Some examples are shown in Table 2.7-1 below. Table 2.7-1: Possible settings for scenes By installing lighting of different colour schemes, a scene could be made more pleasing to the user. LED lighting also makes it easier to display multiple colours. Other scene settings may also incorporate air conditioning and background music to create a more soothing ambience at home. 2.7.3 Master-Off Scene A master-off scene can be programmed and made available on a visualisation panel, with a designated button to turn off a group or all of the electrical loads. For example, it is possible to customise the following master-off scenes: master-off all lighting master-off all air conditioning master-off all roller blinds master-off all electrical loads Using master-off scenes can: save time, as the user can press just one button to turn off a few or all of the electrical loads when leaving the house; and save effort, as the user does not need to check that all the electrical loads have been switched off. Unit 2.7 | Scene Control 121  2.7.4 Using Remote Control to Access Complex Scenes Fig. 2.7-1: Remote controller Remote control allows the user to control devices that are located too far away to be controlled directly. Within a home automation system, electrical loads can be controlled remotely via: infrared, such as infrared controllers that are used at home to wirelessly control air conditioners, DVD players and televisions from a short distance (such controllers require line of sight to operate their respective destination devices); radio frequency (RF), as an RF controller does not require line of sight to operate its destination device and its control panel can be programmed to have wireless scene control of the targets within a certain frequency range; and the Internet – the most powerful method of remote control – such as the internet protocol (IP) camera, which is a type of digital camera used to observe and record activities in a particular place. Unit 2.7 | Scene Control 122  Learning Outcomes Describe and program a central control device for switching, dimming and scene control Convert a conventional lighting circuit to be controlled by a home automation system 2.8.1 Central Control and Visualisation for Switching, Dimming and Scene Control A computer-based central control system can control and monitor the lighting, ventilation, security, and other mechanical and electrical systems in a building. Central control is especially useful in large installations such as private residential estates, shopping malls and commercial buildings. Graphical visualisations give an overview of the values of sensors, switches, and allows the operator to change setpoints (e.g., the desired temperature, securing rooms, monitoring the movement of people, etc.). Graphical visualisation and access to current operating conditions, historic data, and alarm lists of technical building systems and components are crucial for the running of modern building automation. For instance, the building management system of a condominium can integrate the lighting in common areas such as the carpark, gardens, and walkways as well as air conditioning in the clubhouse. A control panel for a home environment can be designed as shown in Fig. 2.8-1. Fig. 2.8-1: Central control for the home The user can use the control panel to monitor and control the lighting (switching and dimming) and air conditioning in different parts of the house. Today, this control panel can also be programmed such that the user can access it via his/her mobile phone for greater convenience. Unit 2.8 | Central Control and Visualisation 123  2.8.2 Convert Conventional Lighting Circuit to Home Automation System While it is best to install a home automation system in a new house or building, it is also possible to convert a conventional electrical lighting system to be controlled by a home automation system. The scale of conversion work varies from system to system. Fig. 2.8-2 shows how conventional lighting switches are replaced and converted to the Z-Wave system. Fig. 2.8-2: Converting conventional switches into Z-Wave switches After the hardware is installed, the technician configures the Z-Wave switches to work with the Z-Wave controller. He then designs and creates the application software to be installed on a mobile device for remote control. Unit 2.8 | Central Control and Visualisation 124 Learning Outcomes State how a controller communicates with the home automation system State the purpose and benefits of using a home automation controller List common hardware modules for a home automation controller, such as: o Universal communication module (UCM) o Input/output expansion board o Keypad o Direct digital controller (DDC) Install and configure a home automation controller to communicate with devices and control electrical loads correctly Use a home automation controller to automate the activation of devices and electrical loads correctly, based on a given scenario Send commands to devices and electrical loads (e.g., switches, dimmers, blinds, buzzers) Monitor energy usage of electrical devices Unit 2.9 | Home Automation Controllers 125  2.9.1 How a Controller Communicates with a Home Automation System The Z-Wave protocol has two basic types of devices: controllers and slave nodes. Controllers are the nodes in a network that initiate control commands and send the commands to other nodes. Slave nodes are the nodes that reply to and execute the commands. They can also forward commands to other nodes; this allows the controller to communicate with nodes that are too far away to be reached via radio waves. Fig. 2.9-1: How controllers communicate in a home automation system 2.9.2 Purpose and Benefits of Using a Home Automation Controller In the Z-Wave system, a controller is a Z-Wave device that has a full routing table and can communicate with all nodes in the Z-Wave network. The functionality of a controller depends on when it enters the Z-Wave network. When a controller is used to create a new Z-Wave network, it automatically becomes the primary controller. The primary controller is the master controller in the Z-Wave network and there can only be one in each network. Only primary controllers have the capability to include and exclude nodes in the network, and thus have the latest network topology. Controllers added to the network using the primary controller are called secondary controllers, which are unable to include or exclude nodes in the network. Unit 2.9 | Home Automation Controllers 126  2.9.3 Common Hardware Modules for a Home Automation Controller (a) Universal Communication Module (UCM) Fig. 2.9-2: Universal communication module (UCM) The universal communication module (UCM) is a device used to link or bridge different channels or home automation systems so that they can communicate. A standard UCM allows programs on the non-volatile memory board to be transferred to or from a home automation system. The UCM allows a computer or another controller to communicate with a home automation system using any of the following methods: RS232 (serial data communication link between hardware and computer); audio (through speaker and microphone connectors); infrared (different signals of different devices can be captured and saved); or Universal Serial Bus (USB). Unit 2.9 | Home Automation Controllers 127 (b) Input/Output Expansion Board Fig. 2.9-3: Input/output expansion board Input/output expansion boards are designed to cater to the needs of controllers that are manufactured with a fixed number of input and output ports. Input ports are for input devices such as push buttons and temperature sensors, while output ports are for output devices such as lamps and buzzers. The input/output expansion modules allow us to increase the number of input and output ports. However, the expansion output current should not exceed 150 mA for any one output or 300 mA for all outputs. (c) Keypad Fig. 2.9-4: Keypad The keypad has a built-in speaker with a microphone and an infrared signal receiver. It can be used to arm and disarm a home security system, record and play messages, control home appliances and act as a baby monitor, with an interactive voice menu to guide the user. Keypads with an LCD touchscreen display are also available. Unit 2.9 | Home Automation Controllers 128 (d) Direct Digital Controller (DDC) Fig. 2.9-5: Direct digital controller (DDC) The direct digital controller (DDC) is another programmable controller that is equipped with features such as timer controls, math controls, scheduling and logic gates. It is also capable of proportional-integral-derivative (PID) control, a control loop feedback mechanism used in industrial control systems to continuously check and calculate an error value against the desired value. The DDC has analogue and digital inputs as well as outputs. Unit 2.9 | Home Automation Controllers 129  2.9.4 Fibaro Z-Wave System Fig. 2.9-6: Fibaro Z-Wave system The training kit used in this course uses the Fibaro Z-Wave system, which provides a direct connection between the signals in the emitters; the devices are connected in a mesh typology. Each system component serves as a signal emitter and receiver as well as a signal repeater. Fig. 2.9-7: Mesh typology in the Fibaro system Each Z-Wave network has its own home ID, which allows for more independent Fibaro systems to operate in the same building without any interference. Each device in the network has a unique node ID, while each device that is newly added to the network is assigned a home ID and a node ID from the controller. All devices within the same network have the same home ID, while the node ID is unique to each device. If another controller, or a secondary master, is added to the network, it shares the same home ID as the main controller. Unit 2.9 | Home Automation Controllers 130