Feeder Pillar Cable Entry: Top or Bottom?
Why Cable-Entry Position Matters Before Fabrication
The electrical specification often states a preferred cable-entry arrangement. The site trench, duct routes and termination points may tell a different story. Once the steelwork starts, changing the entry position becomes expensive and slow.
Top entry suits overhead cable runs or situations where ducts arrive high on the structure. Bottom entry suits underground trenches and ducts that rise through the foundation. The choice affects gland plate location, internal clearances, busbar routing and overall height.
We start every feeder pillar design by mapping the cable paths. This single step prevents the common mismatch between drawing and reality.
Wrong entry position forces changes to gland plate size and thickness. It can leave insufficient bending radius for larger SWA cables. Internal space for switchgear becomes cramped once extra cable length fills the cabinet. Termination points may sit too high or too low for comfortable working. The result is longer installation time, potential non-compliance with the original specification, and extra cost.
We see these issues regularly when a project begins with a catalogue product rather than a design matched to the cable routes.
How Cable Routes Affect Pillar Dimensions and Gland Plates
Cable routes dictate the minimum height of the pillar and the depth needed for proper cable sweep. Larger cables require greater clearances between the gland plate and the first termination. Multiple cables demand a bigger gland plate or several separate plates.
The plate itself must match the cable diameters and the sealing method. Undrilled plates allow site teams to cut exact holes. Pre-drilled plates speed installation when the cable schedule is firm. Plate material and thickness must support the weight and mechanical stress of the cables without distortion.
Pillar width and depth grow when cables enter from opposite sides or when outgoing circuits leave in different directions. Our design process accounts for these factors, so the finished feeder pillar arrives on site ready for the actual routes.
What Information the Enclosure Manufacturer Needs
Clear information early in the process produces the right enclosure first time. We need:
- Cable sizes, types and quantities for incoming and outgoing circuits
- Preferred entry positions and any constraints from trenches or ducts
- Termination heights and required clearances
- Gland plate preferences (material, thickness, drilled or undrilled)
- Overall space limits and access requirements for future maintenance
- IP rating and any environmental conditions that affect sealing
Drawings of the cable routes or a simple sketch of the trench layout help us position openings accurately. Details of the low voltage switchgear layout complete the picture. With this data, we can finalise dimensions, plate positions and internal supports before any metal is cut.
How A&T Can Manufacture the Feeder Pillar Around the Cable
A&T Enclosures builds every feeder pillar to the project’s specific cable arrangement. Our engineers work from the information you supply and produce detailed fabrication drawings. We locate gland plates exactly where the cables will arrive. We size the enclosure so bending radii stay comfortable, and terminations remain accessible.
All punching, forming, welding, and finishing happen in our own facility. This control lets us adjust plate thickness, add reinforced areas around entries, or incorporate multiple entry zones without relying on later site modifications. Bottom cable entry and exit form a regular part of our recent feeder pillar projects. We treat top entry the same way when the site demands it.
The finished unit houses the switchgear securely and presents clean, correctly sealed cable entries. Installation teams connect the cables without improvisation. The enclosure meets the electrical specification and the practical realities of the trench and route layout. Cable entry position is a design decision, not an afterthought.
Share the cable routes and termination requirements with us early. We will design and manufacture a feeder pillar that fits the site as it stands, not as a catalogue assumes it should be.