Benefits of bespoke motor control centres (MCCs)
One of the cornerstone works of Renaissance art is the ceiling of the Sistine Chapel, which was commissioned by Pope Julius II and painted by Michelangelo between 1508 and 1512. The nature of the space required Michelangelo to paint from a unique system of platforms. In the five centuries since its completion, Michelangelo’s masterpiece has been surprisingly durable. Resilience and adapting to a space are two requirements that art and industry have in common, particularly in the case of electrical equipment.
Here, Pat McLaughlin, operations director of Boulting Technology discusses how a made to measure motor control centre (MCC) can benefit both commercial and industrial operations.
The MCC was introduced to the manufacturing industry in 1950; it was launched in the automotive industry, a sector which uses a large amount of electric motors. Over half a century later, not only are motor control centres still in use, but they are extremely common across industrial and commercial applications.
A motor control centre is an assembly of one or more enclosed sections in a metal cabinet containing motor control units with a common power bus. It can also include variable frequency drives, programmable logic controllers and metering and can act as the service entrance for the building’s electricity.
Why an MCC?
Power distribution in large commercial and industrial applications can be complex, but with the help of an MCC, organisations can simplify the process. The entire MCC can be powered through one cable as opposed to the more complex option of using individual cables for each motor.
MCCs are primarily used for low voltage three phase alternating current motors between 208 V and 600 V. The power distributed from these motors can be used in a variety of applications including heating, cooling, lighting or motor driven machinery.
The main purpose of a motor control centre is to protect valuable electrical equipment. Using an MCC with the wrong specification can lead to problems including damage to components that may ultimately result in downtime. For this reason, it is important to purchase the right MCC to safeguard the rest of the system. Before commissioning the MCC, the client should consider the amount of current the horizontal bus should take, the bussing material and the feeder cables to ensure that the motor control centre will be safe in the long term.
Possibly the most important factor to consider when purchasing an MCC is the space and environment that it will go into. The MCC acts like the heart of a building, but its location doesn’t always reflect its importance, with MCCs often being cramped into ill-suited spaces. If the location of the MCC isn’t considered early on, it can be tricky to get a standard, off the shelf MCC to meet the requirements of the remaining space. This is one of the major benefits of commissioning a bespoke MCC.
Fitting the space
A bespoke MCC is the best way to get around spatial restrictions. A company can specify its technical requirements including how many starters are necessary and the dimensions of the available space. The MCC manufacturer can then create and discuss a proposal that is suitable for the company’s needs.
Bespoke MCCs designed and built by Boulting Technology can fit into almost any space through innovative L-shaped, U-shaped and back-to-back designs, that can reduce the overall footprint of the equipment. Boulting Technology offers genuine back-to-back designs that share both the main distribution bars and the risers. This differs from another common method of bespoke MCC manufacturing, where two linear lines are doubled back on themselves, thus doubling the depth. A genuine back-to-back MCC is more cost-effective as well as having half the footprint, which makes a genuine difference, especially when space is limited.
Electrical equipment design is a complex process and each production space has different requirements. While back-to-back MCCs may be most suitable for some environments, a U-shaped MCC could work better for others. Only an experienced consultant will be able to provide an accurate recommendation of the best MCC design for the space at hand and process specific requirements.
As well as meeting spatial requirements, bespoke MCCs can be designed to the exact technical demands of a company’s processes without being limited to the standard options given by the manufacturer. By working with an independent MCC specialist, companies can mix and match components from different manufacturers instead of having to go for a predesigned standard model. Using an independent vendor can speed up the process of creating a bespoke item as an MCC can be constructed with products the manufacture already has in stock, speeding up the build process by using an intelligent CAD package that is linked to the product directory.
One design feature that can make MCCs easier to maintain and replace is the option to have withdrawable starters. The benefits of this can be reaped in facilities that run numerous processes simultaneously, for example in water and waste water facilities or an oil or gas company. Recently, a utilities company commissioned a bespoke MCC for 16 starters for its pumps. The company required an MCC with a small footprint. A withdrawable MCC was the only type of equipment that could fulfil all these requirements simultaneously.
A bespoke MCC can also be designed so that it is suitable for the conditions of the space it will operate in. Some environments can be much harsher so components with higher ingress protection (IP) ratings may be required to safeguard the equipment from foreign bodies, humidity or other environmental factors.
Although Boulting Technology’s bespoke MCCs meet the mandatory BS EN 61439 standard at all times, different industries may also have additional specifications. Liaising with an experienced engineer throughout the design and build stage can guarantee that the MCC meets all relevant industry standards.
An independent advisor can also assess whether existing MCC complies with all the relevant industry standards and regulations. Because MCCs have a long lifespan of around 25-30 years, the design of a bespoke MCC must be made to meet all future challenges. In the case of older MCCs, it is possible to replace or upgrade panels to meet new specifications, although commissioning a new one might often be a wiser decision but in an ideal situation, an MCC should be equipped for future challenges from the onset.
What are the downsides?
The perceived downsides of commissioning a bespoke MCC are that it is an expensive process with more work involved when connecting and disconnecting terminals. There is also concern about how long the bespoke MCC will take to manufacture. However, bespoke MCCs can be made in six to ten weeks, depending on size. Boulting Technology boasts an impressive 25,000 square feet UK manufacturing facility and an experienced and knowledgeable workforce, capable of delivering bespoke MCCs in short time frames.
A further perceived downside of commissioning a new MCC is that may involve some element of downtime. However, in a recent project for a global chemicals producer, Boulting Technology limited downtime by keeping one half of the motor control centre live whilst the other half was replaced. The project took place over the bank holiday weekend to prevent the plant from shutting down during normal working hours.
In the last half a century, the MCC has been a crucial technology in simplifying power distribution. While an off-the-shelf motor control centre might be suitable for many applications, a bespoke MCC offers powerful benefits in a flexible footprint, better use of space and suitability for its environment. Just like Pope Julius II commissioned Michelangelo to undertake a unique project, purchasing a bespoke MCC may be the key to a resilient design, perfect for your space.