It is impossible to tell how many motors a manufacturing plant has. These motors are indispensable for the operation of equipment whether they are small or large. To ensure that the control of all these motors is centralised, motor centres are created.
There are companies that design these centres whether the requirement is a high, medium or low voltage motor control centre. This is the main classification for the centre. Low voltage is the range between 230V to 1000V. High voltage and this can go up to about 15kV. A motor control centre or MCC is a metal cabinet and this is separated into different sections. There are specifications for the enclosure of a motor control centre to ensure its safety. These safety measures include IP rating to protect contamination, protection of dust or temperature etc. The motor control room is in a secure location so that it is kept away from the equipment of the manufacturing plant. Some plants tend to keep them in climate controlled rooms to ensure no contamination. Motor control centres ensure that power is distributed to the equipment. There is a horizontal main bus that distributes the power carrying three-phase power. Each compartment of the motor control centre has a vertical bus. These compartments are the sub-sections within the motor control centre for equipment, wireway and the bus.
Hardware such as contactor and motor starters for starting and controlling the operation of the motor control centre is installed in the equipment component. Other hardware that is included are fuses, circuit breakers, protection equipment that prevents overloading and hardware to disconnect the power. You will be able to see variable frequency drivers in these centres as well. If this component is not there, you can see programmable automation controllers or logic controllers instead. There is a risk involved when it comes to safety of people and machinery because motor control centres have high voltage equipment. But there are many safety features that are included to make sure that this risk is minimised. There is a chance of the occurrence of an arc flash in the case of low and medium voltage motor control centres. There are specialised solutions that are provided to prevent this and also to limit and effect of the actual event.
In addition to feeding the circuits, a motor control centre also controls and provides protection to the circuits. There are two types of wiring that are provided for these centres that are Class I or Class II. When a manufacturing company is working with the professionals that carry out the design, they can specify how they want the units within to be arranged physically. Motor control centres provide a valuable link between the generation equipment and the consumers that you find at the end of the chain such as engines, AC equipment etc. It is a compact unit that allows different areas of the manufacturing plant to be controlled in one place. This ensures that equipment cost is reduced.