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• Arc flash certifications that include operator and equipment safety
• Industry-leading short circuit ratings
• An Ingress Protection safety rating of at least IP2X (‘ finger safe ’) and , if possible , options for IP3X (‘ tool safe ’)
Also , look for a busway system that gives you multiple ground path ( earthing ) options :
• Safety – The elements of a busway system should guarantee safety for your workers , your IT infrastructure and your facility .
Here we will explore the individual elements of a
track busway system , with a focus on ‘ safety ’.
The importance of safety
Safety of equipment is paramount in the data centre – first and foremost , to protect the workers who work there ; secondly , to protect the IT infrastructure and the data that it processes ; and finally , to protect the facility itself . Busway systems offer significant safety advantages over RPPs and greatly reduce the risks of dangerous incidents , such as electrical shocks and arc flash explosions .
Data centre owners have a responsibility to provide employees and electricians with the safest work environment possible . It ’ s crucial that owners and CSEs look for a busway solution that is designed for safety and is certified as safe .
Design elements of a busway system
There are four primary elements that make up a busway system . These are :
• Track busways
• Joints
• Plug-in units ( or tap boxes )
• Power monitoring
• Standard ( protective ) ground system – The busway ’ s aluminum housing provides the system ’ s ground conduction .
• Isolated ground system – The ground conductor and the housing ground are isolated from each other in all components ( this can be useful for protecting certain types of IT loads ).
• Dedicated ground system – The ground conductor and housing ground are bonded together at the end power feed .
Joints
A joint provides a connection between adjacent busway sections , or between a straight busway and an elbow or tee section . Different busway providers use different types of joints . But you should look for vendors that utilise the most reliable kind of joint – a compression-fit joint .
The housing couplers in the joints carry ground conduction through the aluminium housing from busway section to section . It ’ s therefore important to find a busway solution with reliable , well-designed joints in order to properly maintain the ground conduction system .
The problems of bolted and male / female joints
In selecting a busway system , you should avoid solutions where busway sections utilise bolted joints , which are less reliable than a compression-fit joint . In a bolted joint , bolts are used to press flat busbars together . Over time , the bolts can loosen , again resulting in a poor electrical connection . In a worstcase scenario , the joint can heat up to the burning point and potentially cause a fire in the data centre .
You should look for a busway system that includes multiple provisions to deal with potential arc flash scenarios . The solution should have the following :
• Certifications from nationally-recognised test labs
• Selective coordination of fuses which , in the event of a power surge , allows the busway system to lower potential incident energy to negligible levels
Bolted joints must frequently be checked via thermal imaging and re-torqued in order to maintain busway joint integrity . This adds to maintenance troubles and costs , especially in large data centres where thousands of bolted joints must be continuously serviced .
You should also avoid male and female joint couplings , which are easy to install incorrectly . The two busway
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