When designing a capacitor bank, many factors must be taken into consideration: rated voltage, kvar needs, system protection and communications, footprint and more. These factors govern the selection of the capacitor units to be used, along with proper grouping of these units.
Each unit should be rated 9.96 kV and 667 kvar. For a fuseless bank, capacitor units are only connected in series (illustrated in Figure 10); they are never placed in parallel like an externally or internally fused capacitor bank.
Where the DC Capacitor Unit(s) are housed within an Earthed enclosure, the distance of 0.8m may be reduced accordingly, however the inspection shall take place from outside of the enclosure (i.e. through open doors, inspection panels etc).
Capacitor Unit(s) shall first be visually inspected at a distance no less than 0.8m from exposed Capacitor Unit terminals, Charged Capacitor Rack(s), fuse(s) or associated busbars and connections to identify any abnormal Capacitor Unit(s).
Standard-duty capacitors are designed to the IEEE 18-2002 standard and are typically used in utility transmission and distribution applications, whereas heavy-duty capacitors are designed to the IEEE 18-2012 standard for applications where higher reliability is needed.
8.3 The Capacitor Unit shall be short-circuited by connecting a clip-on Short-Circuiting Lead between the capacitor low voltage terminal and the bushing. If the capacitor unit has two bushings, a second Short-Circuiting Lead shall also be connected between the second bushing terminal and the Capacitor Unit container.