C-Bus® Basic Training Manual Volume 1 1A. Introduction to C-Bus 1B. C-Bus Concepts 1C.
© Copyright Clipsal Australia Pty Ltd 2007. All rights reserved. This material is copyright under Australian and international laws. Except as permitted under the relevant law, no part of this work may be reproduced by any process without prior written permission of and acknowledgement to Clipsal Australia Pty Ltd. Clipsal is a registered trademark of Clipsal Australia Pty Ltd. The information in this manual is provided in good faith.
Contents Volume 1A. Introduction to C-Bus 1.0 2.0 Scope 7 Learning Outcomes 7 Introduction – What is C-Bus? 8 Why Use C-Bus? 9 1.1 Ease Of Wiring 10 1.2 Flexibility 10 How C-Bus Works 10 2.1 C-Bus Network Wiring 10 2.2 C-Bus Units 11 2.3 Simple Control 11 2.4 Multiple Events 11 2.5 Control Flexibility 11 2.6 Types of Units 12 System Support Devices 12 Input Units 12 Output Units 12 3.0 C-Bus Communications 13 4.0 Wiring Methods 15 4.
Contents Volume 1A. Introduction to C-Bus 10.0 Address Structure 27 10.1 Unit Address 28 10.2 Group Address 29 10.3 Area Address 30 11.0 Programming Technique 30 12.0 C-Bus Tools and Functions 31 12.1 Local Toggle Buttons 31 12.2 C-Bus Network Analyser 5000NA 31 12.3 Learn Mode 31 Contents Volume 1B. C-Bus Concepts 1.0 2.0 4 Scope 33 Learning Outcomes 33 C-Bus Network Specifications 33 1.1 Cable Type 33 1.2 Maximum Cable Length 35 1.3 Mains Segregation 36 1.
Contents Volume 1C. C-Bus Hardware 1.0 2.0 3.0 4.0 Scope 46 Learning Outcomes 46 System Support Devices 46 1.1 Power Supply 47 1.2 Network Bridge 48 1.3 PC Interface 50 C-Bus Input Units 51 2.1 Operation of Input Units 52 2.2 Pressing a Button 52 2.3 Sending Input Messages 53 C-Bus Output Units 53 3.1 Voltage Free Relay 54 3.2 Voltage Free Changeover Relay 54 3.3 Professional Series Dimmer 55 3.4 DIN Rail Series Dimmer 55 3.5 DSI Gateway 55 3.
Volume 1A Introduction to C-Bus 6 C-BUS TRAINING MANUAL - VOL 1
Scope This manual provides an installer with basic skills needed to program and use C-Bus. A fundamental technical background is required. The manual includes: • an overview of C-Bus • C-Bus wiring methods • C-Bus terminations • C-Bus power supplies • network burdens • operating parameters • multiple networks • C-Bus addressing concepts. It is an ideal preparation before attending the C-Bus Basic Training Course.
Introduction - What is C-Bus? C-Bus is a microprocessor-based control and management system for buildings and homes. It is used to control lighting and other electrical services such as pumps, audiovisual devices, motors, etc. Whether it’s simple ON/OFF control of a lighting circuit, or variable (analogue) type control, such as electronic dimmable fluorescent ballasts, C-Bus can be used to easily control virtually any type of electrical load.
1.0 Why Use C-Bus There are many reasons to use C-Bus: • it is a highly robust and reliable control system, with a low cost per node • a wide range of tools is available, allowing third party companies to interface with both PC based and embedded systems • a single C-Bus cable connection can control many devices • C-Bus offers the ultimate flexibility in switching and control.
1.1 Ease Of Wiring No point to point wiring is required. All input and output units are looped together with Cat-5 UTP cable. Units do not need to be wired in any particular order. The positive and negative C-Bus terminals on each unit are connected to the appropriate conductors on the C-Bus cable. These two conductors carry a low voltage power supply for the electronics in each C-Bus unit, and also allows digital control signals to be sent between units. 1.
2.2 C-Bus Units All units on the C-Bus network have their own built-in microprocessor, allowing them to operate independently with “distributed intelligence”. This provides extremely reliable and efficient communications. Every C-Bus unit has a unique number, so that all devices on the network can communicate directly.
2.6 Types of Units There are 3 main categories of C-BUS devices. 2.6.1 System Support Devices • Power Supply • Network Bridge • PC Interface • Computer Network Interface (CNI) Unit. 2.6.2 Input Units • Switch Plates (1, 2, 4, 6, 8, 12, 16, 20 or 24 button) • Light Level Sensors • PIR Occupancy Sensors • Temperature Sensors • Real Time Clocks • Auxiliary Input Units • Infrared Receivers • Scene Controllers • Bus Coupler • Thermostat. 2.6.
3.0 C-Bus Communications When a button is pressed on an input unit, a measurement is made of its press duration. This measurement influences the message that the unit issues in response to the button press (depending on its programming). This is illustrated in Figure 1. Figure 1 – An input unit measures the duration of a button press before responding The relevant C-Bus message is then transmitted over the C-Bus network as indicated by the dashed line in Figure 2.
The C-Bus message is broadcast over the bus for all C-Bus units to read, as illustrated in Figure 3. It contains information about the Group Address and the operation to be performed, such as switch on or off. Only the C-Bus units with the same address will respond. Figure 3 – A C-Bus message is read by all C-Bus units connected to the same network Once the C-Bus units have received and interpreted the message, they respond according to their programming, switching the appropriate load (Figure 4).
4.0 Wiring Methods The following sections demonstrate the difference between conventional wiring and C-Bus wiring, when installing a two-way control for four light circuits. 4.1 Conventional Wiring Figure 5 indicates how many wires are needed to perform two-way control between two four-gang plates. As many as 13 mains conductors need to be run between the two plates and the loads. Figure 5 – Conventional wiring of a two-way control for four light circuits 4.
4.3 Wiring a C-Bus Network The C-Bus system is wired using Cat-5 UTP cable. C-Bus Cat-5 UTP has a mains rated sheath (pink) and consists of four colour-coded twisted pairs. The standard colours are: • blue twisted with blue & white • orange twisted with orange & white • green twisted with green & white • brown twisted with brown & white. The conductors within a C-Bus cable are displayed in Figure 7.
4.4 Which Wires to Use In order to maintain noise immunity, the natural twist between pairs must be retained when connecting to the positive and negative C-Bus terminals. It is important that the following Cat-5 conductors are used when making C-Bus connections: • orange + blue for positive C-Bus Wires • orange & white + blue & white for negative C-Bus Wires. Figure 8 shows correct wiring that maintains the natural twist of the C-Bus cable conductor pairs.
4.5 C-Bus Terminations The C-Bus network uses an Unshielded Twisted Pair (UTP), Category 5 LAN cable as the communications medium. The Clipsal catalogue number for this product is 5005C305B. It is recommended that the C-Bus cable be terminated by twisting the pair together or by using a bootlace crimp as shown in Figure 10. When terminating the C Bus cable, do not solder as in Figure 11. This may cause “cold flow”. When twisting the pair together, avoid frayed terminations as shown in Figure 12.
The Clipsal C-Bus data cable is strongly recommended due to its distinctive pink outer sheathing. This reduces confusion between a C-Bus network and information systems (such as data, fire and telephone), at the same installation. The Cat-5 UTP also has a 240V mains rated outer sheath. This is a requirement where the cable enters a switchboard, and is present in the same enclosure as single insulated mains wire. The RJ45 end is an 8-position modular connector that looks like a large phone plug.
4.7 Location of C-Bus Units It is important to choose a suitable location to mount a C-Bus unit. Input units are typically located in a position convenient for the people who will operate them. DIN Rail output units are typically installed inside a power distribution board or cabinet. Some important factors to consider: • ensure the mounted unit will not be subject to high temperatures. Most C-Bus units are rated to operate at an ambient temperature of up to 45 °C.
5.0 Mains and C-Bus Segregation With all C-Bus units that have mains as well as 36V d.c. bus connections, care must be taken to adequately separate the 240Va.c. wiring from the bus wiring. Pink C-Bus Cat-5 UTP, with its mains rated outer sheath, must be used within the confines of a switchboard. Wiring practices vary from installer to installer. Sometimes the mains cable entering the switchboard is double insulated, while other times it is single insulated.
6.0 C-Bus Power Supplies The two-wire connection between C-Bus units serves two purposes. It is the communication medium through which on and off signals are sent between inputs and outputs. It also carries a 36Vd.c. supply to power the electronics in C-Bus units. 6.1 Voltage and Electrical Characteristics The C-Bus power supply is isolated from the mains supply by at least 3kV. It achieves this isolation using a double wound transformer. The output voltage is capped at 36V.
6.5 Types of Power Supplies C-Bus power supplies are available in a number of configurations. These include stand-alone units, and supplies incorporated into relay or dimmer output units. Table 2 lists the output currents of various power supply types.
8.0 C-Bus Operating Parameters The following are important considerations when planning a C-Bus network: 1. The maximum total length of Cat-5 UTP cables on any one C-Bus network is 1 km. 2. The maximum recommended number of C-Bus units on any one network is 100 units. The actual number is dependent on the impedance and amount of flowing current. The current must not exceed 2A. 3. Multiple C-Bus power supplies can be connected to a C-Bus network to provide sufficient power for C-Bus units.
9.0 C-Bus Multi Network Installations A C-Bus system cannot be expanded past a certain point without the inclusion of a C-Bus Network Bridge. A bridge splits the installation into separate networks, which are electrically isolated from each other. It can be programmed to allow communication between networks. A bridge must be added whenever the current requirement (or the number of units) exceeds the C-Bus limit, or when the total length of Cat-5 cable exceeds 1 km.
A daisy chain configuration must not exceed six bridges deep. An example of a multiple network connected using this configuration is shown in Figure 14 . Figure 14 – Example of a multiple network connected using a daisy chain configuration Figure 15 shows an example of how a combination of star and daisy chain topologies may be used. There are hundreds of possible combinations.
10.0 Address Structure Several types of addresses are used when communicating with C-Bus units. These are described in Table 3. Network Address Identifies each network. Network Addresses range from 000 to 254 (255 is reserved). Unit Address Identifies each individual unit on a C-Bus network. Unit Addresses range from 000 to 254 (255 means undefined).
10.1 Unit Address The Unit Address ranges from 000 to 254. It gives each unit on a C-Bus network a unique identity. There are 255 addresses available that can be displayed in decimal or hexadecimal format. Figure 16 illustrates how Unit Addresses are used. 240Va.c. Figure 16 – Unit Addresses No two C-Bus units on the same network may have the same Unit Address. The C-Bus Toolkit software will recognise any such conflict, and resolve it by assigning a unique Unit Address to one of the units.
10.2 Group Address The Group Address determines which button inputs control which output channels. There are 255 addresses available (000 to 254) that can be displayed in decimal, hexadecimal* or text format (Tags) † . Figure 17 illustrates how Group Addresses are used. 240Va.c. Figure 17 – Group Addresses (Shown as Tags) NOTE * Hexadecimal refers to the base-16 number system, which consists of 16 unique symbols - the numbers 0 to 9 and the letters A to F.
10.3 Area Address The Area Address is used to simultaneously control all channels on a C-Bus relay or dimmer unit. Figure 18 illustrates how Area Addresses are used. 240Va.c. Figure 18 – Area Addresses Individual relay and dimmer channels can also be controlled from their local toggle buttons (unless disabled by software). 11.0 Programming Technique All C-Bus units leave the factory with a default undefined Unit Address value of 255.
12.0 C-Bus Tools and Functions 12.1 Local Toggle Buttons DIN and Pro series C-Bus outputs are equipped with local toggle control for each output channel. These toggle buttons operate as long as mains voltage is connected to the DIN unit. They do not require the C-Bus connection to be wired in. Pressing a local toggle control button will alternately switch the load wired to the respective channel, on and off.
Volume 1B C-Bus Concepts 32 C-BUS TRAINING MANUAL - VOL 1
Scope This manual aims to provide an installer with the basic skills needed to program and use C-Bus. A fundamental technical background is required. This manual covers: • various C-Bus network specifications • C-Bus addressing concepts. It is an ideal preparation before attending the C-Bus Basic Training Course.
IMPORTANT Using the above pairing ensures a mutual twist between conductors and C Bus terminals, providing increased immunity to electromagnetic interference. It is recommended that the C-Bus cable be terminated by twisting the pair together or by using a bootlace crimp as shown in Figure 1. Figure 1 – Terminating with a bootlace crimp When terminating the C-Bus cable, do not solder as in Figure 2. This may cause “cold flow”.
1.2 Maximum Cable Length On any given C-Bus network, the total length of Cat-5 UTP cable used must not exceed 1 km. This figure is determined by the propagation delay of C-Bus communication at a total cable capacitance of 100nF. Large cable lengths can introduce undesirable effects on the network such as: • a drop in voltage • an increase in cable capacitance. A voltage drop will occur because the Cat-5 cable has a resistance of 90Ω per kilometre.
1.3 Mains Segregation With all C-Bus units that have mains as well as 36Vd.c. bus connections, care must be taken to adequately separate the 240Va.c. wiring from the bus wiring. Pink C-Bus Cat-5 UTP, with its mains rated outer sheath, must be used within the confines of a switchboard. Wiring practices vary from installer to installer. Sometimes the mains cable entering the switchboard is double insulated, while other times it is single insulated.
1.4 Single Network Topology All C-Bus units may be wired in star, daisy chain or a combination of both configurations. A closed ring configuration must not be used. Wiring the C-Bus network in this configuration will cause erratic behaviour. Daisy Chain The daisy chain wiring configuration (shown in Figure 4), is basically a run of units, connected with its positive and negative terminals in parallel.
1.5 C-Bus Cable Current The maximum amount of current allowed to flow on Cat-5 UTP cable is 2A. This is a limitation of the cable. If 2 A is exceeded, you run the risk of damaging the C-Bus cable. 1.6 System Voltage At all points in a C-Bus network, the voltage across a C-Bus unit must be within the range of 15V to 36Vd.c. However, a C-Bus voltage as low as 15Vd.c., may cause unstable communication. As a rule of thumb, it is strongly recommended that the C-Bus voltage be maintained at 20Vd.c. or higher.
1.8 C-Bus Clock At least one clock must be enabled on the C-Bus Network. In the absence of a C-Bus clock, no communication will be transmitted along C-Bus. Note: This is not a real time clock, but a means by which communication is synchronised. There will only ever be one active clock on the C-Bus network, however it is recommended to have multiple system clock generating units available for a redundant system.
1.9 Network Burden A network burden applies a standard impedance to a C-Bus network. It consists of a 1kW, 0.6W resistor in series with a 10 to 22µF, 50V capacitor as shown below. 10uF - 22uF 50V 1kW 0.6W Figure 7 – A network burden There are two ways in which a network burden may be added • via hardware • via software (by enabling a unit’s in-built burden). A network burden should only be used to adjust the network impedance to between 400W and 1.5 kW.
2.0 C-Bus Addressing Conventions Several types of addresses are used when communicating with C-Bus units. 2.1 Network Address A C-Bus network is a collection of C-Bus devices connected together using Cat-5 UTP LAN cable. The network size is dependent on various factors such as: • the Cat-5 cable length • the number of units per network • the total current drawn on the Cat-5 cable. The Network Address is a code assigned to each network within a particular project.
2.3 Application Address An Application Address is used together with a Group or Area Address to identify one or more units, inputs or outputs. It provides a convenient way to separate units and their associations, into different categories. The default Application Address is “lighting”. The programmer can specify up to 255 Application Addresses.
2.4 Group Address Within any application, Group Addresses are used to communicate between all units on the C-Bus network. The C-Bus addressing scheme allows you to define up to 255 different groups per application. Using Group Addresses to communicate between input and output units, it is possible to emulate or expand beyond the functionality of conventional wiring. Messages broadcast by an input device will be seen by the entire network, but only the units with a corresponding Group Address will react.
2.7 C-Bus Tags A C-Bus address can be used in raw numeric form, or it may be assigned a meaningful name, known as a Tag. A Tag is user defined. Table 3 to Table 7 list typical tags you could use for various address types.
Volume 1C C-Bus Hardware 1C.
Scope This manual provides an overview of various units used in a C-Bus network. A fundamental technical background is required. The manual covers: • system support devices • input units • output units • C-Bus indicators. It is an ideal preparation before attending the C-Bus Basic Training Course.
1.1 Power Supply The C-Bus power supply is a switch mode device, which means it is efficient and compact. It converts mains voltage into a usable C-Bus voltage of 36Vd.c.. It is the C-Bus power source, providing power to each unit on the network. The C-Bus system operates at an Extra Low Voltage (ELV) level. The minimum voltage required by each device on the bus is 15Vd.c.. However, a voltage this low may cause communication to be unstable.
AC Output Impedance C-Bus messages are voltage pulses which are superimposed over the d.c. power supply voltage. This requires a high a.c. impedance to be present at communication frequencies. The power supply has a special output stage that provides this impedance. General purpose off-the-shelf power supplies are not suitable for C-Bus installations. 1.
A network bridge consists of two functionally and electrically independent systems. Each system consists of a communication interface and microcontroller, powered by the ELV C-Bus power from the networks to which it is connected. Each Network Bridge provides optically isolated communication between sub-networks, so the reliability of the overall system will not be impaired by introducing bridges.
1.3 PC Interface A PC Interface provides a communication path between a personal computer and a C-Bus network (see Figure 2). With a PC Interface and the C-Bus Toolkit software, you can: • program and issue commands to C-Bus units • monitor a C-Bus network, logging network activity. A C-Bus PC Interface can: • generate a system clock for synchronised data transmissions • apply a network burden to the C-Bus network.
2.0 C-Bus Input Units C-Bus input units respond to certain stimuli (such as touch, ambient light conditions, temperature and infrared radiation), by sending messages to appropriate output units in a predetermined way. There are various types of input unit: • wall switches (1, 2, 4, 6 or 8 channel), as shown in Figure 3 • light level sensors • PIR occupancy sensors • temperature sensors • real time clocks • auxiliary input units • infrared receivers • scene controllers • touch screens.
2.1 Operation of Input Units Any network needs to have input and output capabilities. Therefore, input units are a fundamental building block of a C-Bus system. Input units can only broadcast three types of commands on a C-Bus network. These are: • on commands • off commands • ramp to (level) commands. When a button is pressed on a wall switch, a message is sent across the C-Bus network for an output unit to perform one of the three functions above. An input unit can also perform timing functions.
2.3 Sending Input Messages When a C-Bus input or output unit receives a message, it performs a function described in Table 1. Any internal timers (input units only) on the same Group Address will be forced to cancel. On A unit’s internal level is set to maximum and its status is set to on. Off A unit’s internal level is set to zero and its status is set to off. Ramp To Level A unit’s internal level is set to the level contained in the message.
3.1 Voltage Free Relay The C-Bus 55xRVF Series Voltage Free Relays are relay-switching devices designed to be mounted in electrical switchboards or similar enclosures (an example is shown in Figure 4). For ease of installation, they are DIN rail mounted, measuring 12 DIN modules wide. Several independent voltage free relay contacts are provided for general switching applications. The series includes units with 10A rated relays for resistive, inductive (lighting loads) or fluorescent loads.
3.3 Professional Series Dimmer The Lx510xDx Professional Series Dimmers are C-Bus output units suitable for dimming resistive and low voltage loads in lighting applications. Each channel is load rated between 5A and 20A (depending on the unit’s model).
3.6 Analogue Output Unit The DIN rail mounted Analogue Output Unit provides analogue voltage control signals. These can be used to drive most types of 0 to 10V electronic dimmable ballasts used in the lighting industry. The 0 to 10V signal may be used to control other equipment with this standard control input voltage. The signal direction ranges from 0 to 10V, as the C-Bus ramping level increases from 0% to 100%. The Analogue Output Unit operates in response to commands from C-Bus input units.
4.0 C-Bus Indicators All C-Bus Output Units (apart from the Infrared Transmitter) have three types of indicators that serve a common purpose. Figure 5 and Table 2 show the location of the indicators on a C-Bus output unit, together with their explanation. For the specific functions of various indicators, please see the relevant installation instructions that come with the C-Bus units.
Notes 58 C-BUS TRAINING MANUAL - VOL 1
Notes 1C.
Notes 60 C-BUS TRAINING MANUAL - VOL 1
Notes 1C.
Index Volume 1A. Introduction to C-Bus Volume 1B.
Index Volume 1C.
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