Electrical distribution switchboards and motor control centres
An MCC, distribution board or electrical switchboard needn't be a complex structure if all the elements are considered.
Electrical distribution and motor control has a major role to play in today's industry. The systems that control these are usually referred to as a Motor Control Centre (MCC), Distribution Board or Electrical Switchboard. Every compartment within an MCC, distribution or switchboard will normally house a circuit breaker and/or a motor starter, normally side by side with sufficient space left over for control, power transformer and a relay.
With modular MCCs, distribution or switchboards, it is essential that a level of separation is achieved and these forms of separation extend from Form 1, which is based on a traditional open 'cabinet' type MCC construction, to the extremity of Form 4b Type 7 where all starters or feeders are separated from each other - even the control terminals.
Designing an MCC, distribution or switchboard can be very time consuming, as not only does the front 'general arrangement' require organising to make use of the valuable space, but the internal components require careful planning in order to make sure that fine details, such as mounting plates and busbars, are included.
Rittal Ri4Power represents a uniform system solution for low-voltage switchgear of up to 5500 A in versions 1-4, based on the Rittal TS 8 Top Enclosure system. By combining their Ri4Power low-voltage switchgear with designs 1 and 2-4 to form a single system technology, Ri4Power Form 1-4, allows switchgear manufacturers to fabricate every known form of internal subdivision from one single set of modules. Units for very different needs and applications can be made with one and the same component.
Switchgear manufacturers now have access to three busbar systems for the different performance categories of one single low-voltage switchgear system. Rittal's RiLine60 is a compact busbar system with component and connection adaptors, offering a solution for up to 1600 A, for power distribution at the lower distribution level. Rittal's Maxi-PLS provides a compact busbar system of 1000-4000 A that cuts installation time and their Flat-PLS is a rugged busbar system for currents up to 5500 A, based on flat copper bars, meeting maximum requirements with its' high short-circuit resistance.
Type testing
Type testing in low voltage switchgear is increasingly becoming an issue of prime importance worldwide. Type tested panels, in accordance with IEC 60439 Part 1, assures a high level of personal protection as well as system protection. However, one important thing to remember is to ensure that all the plastic materials used for the busbar supports are self-extinguishing in accordance with UL 94-VO. With such type tests, more safety is assured through heat dissipation and comprehensive short circuit resistance testing. When type tested along with various manufactures protective devices MCCs offer even more flexibility of system permutations.
Rittal's Ri4Power low-voltage switchgear system Form 1-4 has been tested to accommodate circuit-breakers from all well-known manufacturers. Switchgear manufacturers now have at their disposal circuit-breakers from no less than eight manufacturers which can be installed quickly and easily. The consistently modular system and the high manufacturing quality of the Ri4Power Form 1-4 guarantee the ultimate in safety and efficiency during assembly.
It is also possible to plan and configure the various combinations quickly and easily, with the aid of Rittal's Power Engineering software Version 5.0, Rittal's new version of planning and configuration software for type-tested low-voltage switchgear of their Ri4Power systems, Form 1, Form 2-4 and Ri4Power Form 1 ISV. The software offers quick and easy generation of quotations and bill of materials with better assembly information and the capability to view the side of the assembly, where part numbers and their location within the system are indicated.
Software includes project handling that ranges from an automatic generation of bill of materials via price determination, up to material ordering. By means of comprehensive import and export functions it is possible to add third party products, required for distribution, to the software database. Special enclosure designs can be optionally stored in the software as own field types.
Comprehensive help functions lead the user through the programme and explain the necessary steps. When entering some parameters, bill of orders and drawings can be generated for individual field types. The user is able to add further Rittal products or other articles from a self-created article master at any time during field configuration. Included in the bill of materials are new technical brochures; tightening torques for flat-PLS bus bar system and assembly instructions for Ri4Power low voltage switchgear.
After configuration of the individual fields a CAD view can automatically be displayed, printed or exported if required. The generated bills of materials, whose content can be freely generated, can optionally be printed or exported as a file. With the assistance of the integrated assembly planning tool, individual assembly plans can be drawn up for each enclosure field. From these, the switchgear manufacturer can assign the different components quickly and perform assembly smoothly.
With any purchase of a motor control or distribution board it is also important to consider the future use of the equipment. Although it may be suitable for today's business requirements, will it be able to cope with tomorrow's demands? If an extension is needed, can the enclosure units be easily bayed together? Any MCC, distribution board or electrical switchboard needn't be a complex structure if all the elements are considered. With advances in technology and an expanded array of options designed to help deliver improved safety, increased productivity and greater cost savings are possible.
