UPDATED: Control Cabinet Disassembly

After completing a successful R&D project proving and conducting the conversion of chemical to electrical energy stored in battery form, our client sought to decommission the cabinet. As such, it was returned to our workshop where we set about deconstructing the two-piece build.

To begin with, here’s the wall mounted control cabinet before and after, to be followed by the same process for the console standing unit.

What followed was a variety of pushes and turns to remove components and terminals, depending on how they’re designed to fit and slot onto din rails.

Screw Terminal Ports

A screw terminal port allows for electrical connection where a wire is secured by tightening a screw onto a metal conductor to hold the wire firmly in place. They’re one of the most common connection methods in control panels.

Screw terminals consist of three basic parts:

A metal conductor or plate that carries the electrical current.

A screw that tightens down onto the wire.

A housing (usually plastic or ceramic) that insulates and supports the assembly.

When the screw is tightened, it clamps the wire against the conductor, creating both a mechanical hold and an electrical connection.

A stripped wire end is inserted into a slot, they’re always crimped in our panels. Tightening the screw will then:

Compress the wire strands or solid core.

Ensure good electrical contact.

Prevent the wire from pulling out.

Push Terminal Ports

Push‑release terminal ports are electrical connectors that let you push a wire in to make a connection and press a release mechanism to remove it.

This provides fast, tool‑free wiring for solid or ferruled conductors.

These spring-clamps are then released by:

Pressing a push button.

Pressing a release tab.

Lifting a lever.

Below you’ll see different sized flat head screw drivers being used to push release terminals, followed by an example of screw terminal ports on the Brodersen signal converter units and a box full of all removed wires.

Here you can see the removed grey cables and stacked terminals and end plates part way through the process.

Now for all the disconnected B&R modules from the wall mounted control cabinet encompassed of:

• Signal converters
• Bus converter
• Bus module
• Safety module
• PLC I/O module
• I/O modules
• Expansion modules
• Communication interface modules
• PLC module
• Terminal blocks

As you can see, part of the removed din rail has already been cut down and repurposed. Next to that are the removed trunking covers which are slid and slotted into place to cover the wires and cables after full assembly and allowing for access beneath when required.

Here we can see series jumper bars in red, blue, and orange. These comb-like parts are used to keep series of terminal blocks in strict position.

When terminal blocks are mounted to din rails as required, whether by being screwed into position or clipped into position, the jumper bars are slotted in to maintain the integrity of the piece and performance, ensuring that gravity and vibration do not disturb the connections.

When it comes to removing parts, the terminal blocks are coaxed off the din rail as required before and the jumper bars are finally removed.

Next week I’ll share some images and insights of the dismantling of the console standing unit.

Now was the turn of the standing control panel to begin disassembly. One thing you see a lot of in workshops is gardening kneeling pads or similar.

Until you remove the securing part you see in the second picture below, no amount of unscrewing will allow you to remove those elements from the din rail.

The wires were then easily released and further down the din-rail a door front of a component was opened to allow access within.

The metal rod that you see in picture 2 and 3 below is what functions the red rotary handle located on the door of the control cabinet and it was screwed out of position accordingly for removal before moving onto more push releases along components.

As well as risk analysis and cable management, grounding and voltage protection, the IEC 60204-1 standard is mandatory for control cabinet designers and manufacturers to ensure the safety of electrical equipment.

Soon we’ll see the standing cabinet and top door with embedded screen completely stripped back. Till then.