Over the decades, the installation of wiring accessories has been made ever simpler through product development, careful design and technological improvements. So, how is it possible to make it easier still? In fact, there is much room for improvement, as Jane Yorke argues:
While good aesthetics and smart technology have driven much of recent wiring accessory development, have manufacturers forgotten about the installer? Perhaps not, but the evidence would suggest that we could do better.
Many improvements, existing or potential, are just the application of common sense.
Take the humble wall switch. There is an ongoing debate about where exactly you should make the loop connection for the neutral conductor of a lighting circuit. Should it be in the ceiling rose or behind the wall switch using a connector block? There are potential problems with both solutions.
If you make the connection behind the ceiling rose, you will be working above head height. This makes the job both time consuming and awkward and you need to take care to ensure that all of the terminations are secure. Even if they are secure, many would argue that they are not readily accessible for inspection and testing to meet the requirements of BS7671:2008.
The alternative is to complete the neutral loop connection at the switch and to house a joint in that conductor within the enclosure . Both the NICEIC and the Electrical Safety Council state that this is acceptable practice. The switch is at a more convenient height, so it is easier to make the connections and it is readily accessible for future inspection.
Until now, however, the only way to complete this connection is to use a connector block for the incoming and outgoing neutral conductors. Many electricians consider that this is bad practice because the free terminals can move and place strain on the connections. The connector block is pushed into the metal back box, so if a cable becomes detached, this could make the installation live and it also leaves less room for cabling.
Developments by manufacturers can, of course, help overcome such issues. We can, for instance, develop shallower back projections in accessories to free up more space in the back box. As an example, in a new range, sockets project just 15mm back from the faceplate and the wall switches by just 10mm. There is, however, an even more obvious answer. Why not just introduce a neutral loop connection in the switch itself so that a connector block is not needed?
While this is a major omission from wiring accessories there are a number of other improvements that can be made to make the contractor’s job simpler. Even details such as using a slotted screw head for good torque can make a big difference. Terminals should be in line, easily identifiable, orientated for best cable dressing and facing in the same direction. The terminal screws should be captive and backed out and there should be a positive wire end stop.
Most wiring accessory ranges also still use neon light indicators. Not only do these flicker and dim over time, but you need to install thin flying leads into one of the terminals. It is hard to know when the connection is made and it is too easy to over tighten and break the lead. Using an LED light indicator involves no additional installation and the light source remains bright, usually throughout the product’s lifetime.
Ask any electrician on site what they consider to be one of the most annoying areas of their job and many will answer installing grid products. The lack of cabling space and the number of wires to be positioned and terminated can make this particularly awkward and difficult.
There are a number of ways that good design can make the installation of such products easier. The modules should be as shallow as possible to maximise cabling space in the back box. Also, why not clip them in from the front of the metal frame, rather than the back, to make them easier to fit and replace and to ensure that you cannot push them into the back box.
The wiring can also be simplified with the terminals all facing upwards for easier orientation with lead ins to guide the screwdriver, backed off screws held captive, wire end stops, plus clear white labelling off a dark grey background provided.
There’s always room for improvement
The lesson to be learnt from all of this is that, however long a product has been in the market, there is always room for improvement. While good aesthetics are vital, this is not a reason to ignore the development of installer friendly features. Some of these features make life easier and speed up installation, while you could argue that others further improve safety by ensuring termination of conductors.
We are all striving for the best looking easiest to install wiring accessory. By examining installation practice and asking installers, it is surprising just how much room for improvement there really is.