November 2017

November 2017 | Plant &Works Engineering | Process, Controls & Plant 25 Focus on: Drives, Motors & Controls decades old could be revisited to ensure it doesn’t pose any health and safety risks. Regulatory compliance The well-known BS EN 61439-2 standard, which came into play on 1st November, 2014, states that the enclosure of an MCC should fit the “type and degree of protection suitable for the intended application.” Best practice dictates that the enclosure should provide protection for equipment against external influences from any accessible direction and against direct contact, meaning that an ingress protection of at least IP2X is required. Older MCCs may not have been built to this standard, so it’s important to check that your equipment is compatible with the latest regulations. Another critical design verification introduced by BS EN 61439-2 refers to the temperature rise limits of motor control centres. Temperature rise is essential to the reliability and long service capability of an MCC, because excessive temperatures result in the premature ageing and failure of components and insulation. The introduction of the new standard means that manufacturers must verify that each circuit within the assembly can individually carry its rated current. If you are considering purchasing a new MCC, it’s important to make sure that it complies with BS EN 61439. This is the responsibility of the MCC manufacturer, but the client should also be aware of the requirements and the benefits of the new standard. Environmental factors Because MCCs often operate in demanding environments, there are certain environmental factors that can affect the equipment and shorten its operational life. Such factors include dust, moisture and steam, all of which can be very corrosive and damage bus bars or electrical equipment. Similarly, because MCCs are often tucked away in the depths of a building, there is the danger of vermin damaging cables. Maintenance engineers need to be aware of these potentially harmful environmental forces and perform the relevant checks periodically. Although some of these variables — such as moisture or dust — can’t be eliminated, they can be mitigated and engineers can monitor sensitive components more closely. New tech More often than ever, companies are deciding to change or upgrade their MCCs to take advantage of the benefits that new technologies offer. One common upgrade involves replacing conventional starters with variable speed drives (VSDs) and adapting the MCC to accommodate this change. Since a VSD can reduce the energy consumption of a motor by as much as 60 per cent, this type of upgrade helps companies make significant energy and cost savings in the long term. Intelligent MCCs also feature remote controls and better data collection capabilities, which can be used for condition monitoring and preventative maintenance. In turn, this reduces maintenance and breakdown costs in the long run and helps companies minimise overall operational costs and enhance productivity. Regardless of the age of your motor control centre, preventative maintenance is the key to making sure it performs well for longer. For further information please visit: www.boultingtechnology.co.uk n