Ian McWha, Key Account Manager at Boulting Technology, explores the importance of recognising and overcoming challenges when designing a switchboard. When plant managers look to install a new switchboard in their facility, they are often presented with a range of challenges that they must address. Identifying these challenges as soon as possible is imperative to the success of the installation and the functionality of the switchboard. If not addressed, these issues can have drastic consequences, causing production down-time or even damage to other systems and employees.
Each facility is unique and as such will have its own design requirements, dependant on the function of the plant. Many plants have limited space that they are keen to maximise, so the footprint of the switchboard needs to be as small as possible, while ensuring its integrity is not compromised.
Boulting Technology’s designers can create bespoke systems that meet client specifications, particularly in space-short environments. Bespoke MCC designs include integrated back to back systems with shared riser and main distribution bars, custom made U shape centres, L shape units that fit round corners and bridges that extend above equipment and wall partitions.
The specific needs of each job may also present additional challenges that the design engineer must be aware of. When working with pumping stations for example, a switchboard may be required to be near water. In these cases, the Ingress Protection (IP) rating, which classifies the degrees of protection provided against solid objects, dust and water, must be adhered to.
As challenges are often individual to a facility, a unique switchboard may be the answer.
Forward planning is essential when installing new equipment, especially when establishing a regular maintenance programme. Planned and predictive maintenance is crucial to keep machinery working efficiently for as long as possible, avoiding production down-time. To solve this, plant managers should work closely with the switchboard manufacturer to develop a robust maintenance programme.
Boulting Technology offers an all-encompassing maintenance solution, which includes a comprehensive survey that assesses control systems across a facility. An initial online survey assesses areas, such as obsolete parts, equipment lifecycle and efficiency.
From the survey, a series of multi-stage recommendations provide a hierarchy of risk, allowing plant managers to focus on high risk critical systems in the first instance and implement an appropriate plan of action.
Not properly addressing design challenges can cause safety issues. For example, it is essential that the switchboard has the correct rated short time withstand rating. This is the rating of current that the assembly can withstand for a set period of time without the aid of a short circuit protective device (SCPD). The short time withstand rating, used by engineers to determine the ability of the assembly to protect itself and other devices, is made up of two parts - the fault current rating in kiloampere (kA) and the duration time.
Manufacturers also need to be aware of the prospective short circuit current (PSCC) or fault current. The PSCC is the highest electric current which can exist in a system under short circuit conditions.
While engineers should always be aware of the PSCC, specific applications such as when operating transformers in parallel, can present dangerous situations if not managed correctly.
Legislation, such as BS EN 61439 is the first step to ensuring switchboard safety. BS EN 61439 is a mandatory standard for all Low Voltage Switchboard Assemblies (LVSAs) and helps the manufacturer and plant manager ensure the board achieves acceptable levels of performance, safety and reliability.
It is important to choose a manufacturer and integrator which understands the relevant legislation, how to meet them and how to ensure the product is safe, while also meeting customer requests and requirements.
While meeting legislation standards is important, it does not automatically mean the switchboard is fit for the desired purpose. Safety requirements can easily be met without the equipment meeting client specifications or even working correctly. Legislation should be one of many considerations when installing new equipment.
Thinking outside of the box means design challenges can not only be overcome, but can become useful, resulting in bespoke ideas and revolutionary products.