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Visually Interactive Program for Consultant and Owner to Design and Assess Electrical Systems in Buildings
By utilizing the visually interactive window programming technique and facilities on database access, VipCoda provides an user friendly, visually interactive tool to automate the design process producing a sound and reliable design which meets the code of practice of CP5 (1998) and BS 7671:1992 (IEE wiring regulations, 16th Edition). VipCoda can also be used to automatically assess and evaluate any submitted electrical network systematically within a short time. By utilizing the built-in database structure, all the design assumptions are automatically documented and stored together with the completed design network. Thus, it is also a comprehensive tool for training and upgrading engineers on how to design and assess an electrical network. The completed design including all the technical parameters can be displayed and viewed in exactly the same presentation as reading a single-line diagram generated by AutoCAD. In addition, the calculated fault level and the cumulative voltage drops from the main incoming circuit up to each final circuit are graphically displayed. Facilities are provided to simulate the normal loading, overloading, short circuit and earth fault conditions. A result of pass or fail will be given by assessing through seven critical tests and three non-critical tests. A full explanation as to why, how and by how much the design fails will also be included.
All the cable tables given in the IEE wiring regulation and CP5 (1998) are structurally stored in the cable database grouped according to the conductor material, insulation material, and cable construction and installation methods. In addition, fire resistant cables and busways are also represented. Currently, eight types of cables, namely copper PVC, copper MICC, aluminum PVC, aluminum XLPE, copper XLPE, copper fire resistant, copper busway and aluminum busway are available in 763 records. The installation methods include clipped direct, conduit/trunking, thermal insulation and tray for single-core non-armored, multi-core non-armored, single-core armored and multi-core-armored cables. All the cables can be interactively selected from a number of simple dialogue boxes and built-in facilities are provided for the user to have a speed search for all CP5 cable tables. Five types of overcurrent protective device, namely ACB, MCCB, MCB, RCCB and fuse are represented. The complete range of the preferred rated current and breaking capacity from the relevant BS and IEC standard are included in a total of 93 records for breakers and fuses. Four types of typical time-current characteristic curves for breaker and fuses are modeled. Current transformers and earth fault relays by IDMT, DTL and ELR are available. Seven types of critical tests and two types of non-critical tests are conducted for each circuit in each DB to assess whether a given design is acceptable under normal loading, overloading and short-circuit conditions.
Breaker and Cable Load Test.
Compute design current (IB) and the
rated circuit capacity (IZ) by considering the ambient temperature
and grouping factor. Based on the current rating of the protective device (IN),
detect whether IN > IB and IZ > IB.
Compute the circuit loading in percentage of the rated capacity under the
specified conditions. Overload Protection Test. Increase the load current in each circuit to 145% of the rated circuit capacity (IZ) and model the operating time of the protective device. Detect whether the operating time of the protective device is less than the effective operating time of 2 hours. ( i.e. I2 < 1.45 IZ and IN < IZ) Voltage Drop Test. Calculate the voltage drops in volts and in percentage of the rated operating voltage. Check whether the voltage drop is within the required voltage drop tolerance. Short circuit Protection Test. Calculate the 3-phase short-circuit current at the end of each circuit. Check whether the braking capacity of the protective device is higher than the calculated short-circuit current. Model the operating time of the protective device under the fault condition. Detect whether the circuit will be disconnected within the critical time, which is the maximum allowable time in seconds to ensure that the temperature in the conductor will not exceed its thermal limit resulting in a failure in insulation material. Earth Fault and CPC Test. Calculate the earth fault current at the end of each circuit. Detect whether the cable size of each circuit protective conductor (CPC) is adequate to withstand the earth fault current. Motor Starting Test. Based on the type of starter and the motor rating, calculate the motor starting current. Model the operating time of the protective device and detect whether the protective device will trip during the starting period. Based on the circuit impedance and the source impedance, calculate the voltage dips at the instant when the motor starts. Detect whether the voltage dips will release the contactor in the starter. Electric Shock Protection Test. Calculate the earth fault current and the touch voltage at the end of each circuit. Based on the IEE regulations and solely based on the direct acting overcurrent protective device, check whether the touch voltage is less than 50 V and whether the disconnection time is less than 5 s for a TT system. For a TN system, the earth fault loop impedance is calculated and a check is made to detect whether the disconnection time is less than 0.4 s for hand-held equipment and 5 s for fixed equipment. If the direct acting overcurrent protective device fails to provide the requirements for electric shock protection, the relevant residual protective devices such as RCCB, ELR, E/F and IDMT will be suggested. The operating time is modeled based on the specified CT ratio, time and current settings of the device. The user will be prompted to specify new settings until the requirement on electric shock protection is met. 3. Computer-aided Interactive Design The user may carry out the design work for a main switchboard (MSW), a main distribution board (MDB) or a final distribution board (FDB). Facilities are provided for the user to link the complete network by backward chaining from FDB, MDB to MSW, or a forward chaining from MSW, MDB to FDB. For each circuit, based on the user’s specification on the required type of load and power rating, type of cable, circuit length, fault level of the incoming source etc, the program automates the design process and shows the appropriate breaker and cable including CPC in a single line diagram. Through several built-in rules, the automated design done by VipCoda will ensure that it meets all the seven critical tests. The user may simply click on the single line diagram to change a breaker or a cable in any circuit, or to enter a design done by a contractor. The user may click the ‘speed test’ button to obtain summaries of those tests that have detected failure. The user may then click for a particular test to find out the cause of failure or click the ‘redesign’ button to carry out a redesign by the program for one particular circuit, the whole DB or the entire project to automatically rectify all the design errors. Options are provided for load balancing either manually or automatically. Facilities are provided for the user to list or print a technical summary or a cost summary of the whole project. In the technical summary, all the DBs in the specified project are tabulated together with the maximum demand, fault current, earth fault current and the cumulative voltage drop at each DB. For cost summary, the cost for each DB and the total cost of the whole project are listed with breakdown in cable and breaker costs. Tools are also provided for the user to delete or insert a circuit, copy a DB to a project or create a project by modifying from a list of standard projects or previously completed projects. Utilities are also provided for the user to print the single line diagram of a particular DB together with the result of each simulation test. The successfully designed network of a project can be saved by the built-in project database. This database contains the description of all the switchboards and DBs of the whole project in an automatically arranged structure. Built-in editing facilities are provided for the user to view or edit the project database, design element database or lookup tables that contain the design rules and design assumptions. For verification and confirmation that the design process by VipCoda is accurate, three benchmark projects have been created with all the connected loads and design assumptions specified. In these three benchmark networks, the completed design done by VipCoda represents the unique solution that meets all the given design requirements and specifications, and at the same time there is no over-design in any circuit. Thus the completed network given by VipCoda can be used as a reference to compare a design done manually or by using any other computer aided design program. VipCoda utilizes all standard Window facilities such as pull down menus, pop-up windows, symbolic icons and various visually interactive dialogue boxes, etc. It is arranged such that all the menus, icons and dialogue boxes are self-documented. The user may simply click a load icon to view the detailed load information, click a circuit icon to view or change the type of cable, temperature correction and grouping factor or click a breaker icon to re-specify the type of breaker or its tripping curve. Tools are provided for the user to have an enlarged view on a DB or an overview of the whole project including riser with tap-off and the incoming transformer connection.
Send purchase order by e-mail to cyteo@ntu.edu.sg, by telephone call to Byte Power Publications at (65) 6256 0101 and arrangement will be made for site demo/installation. 8. VIEW TYPICAL DISPLAY
Click on the thumbnails below to view typical display
9. VIEW LEAFLET Click on the thumbnails below to view VipCoda Leaflet
10. DOWN LOAD VipCoda DEMO Click on the thumbnails below to down load VipCoda Demo
* Click on the thumbnails below for each sample display
BYTE POWER PUBLICATIONS 10H, Braddell Hill, #23-30 Singapore 579727 Tel: (65) 6256-0101 E-Mail: cyteo@ntu.edu.sg |
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