Given the proven advantages of screwless connection technology, staying with old style screw-type methods really isn’t worth the risk, argues WAGO’s Sarah Burrows.
In recent years, more and more electricians have been switching from conventional screw-type connectors to screwless technology. Spring clamp systems have become increasingly popular amongst domestic electrical installers and inspectors. There are of course, a number of installers who seem reluctant to change and still choose the older-style screw connector products. Some may not fully understand the benefits of screwless technology; they may perhaps view it as more costly – or, because they have always used screw connectors, they see no reason to change.
Screwless technology
The technology is simple. Once the stripped conductor is inserted, the spring clamp applies the precise amount of pressure needed to ensure a safe and reliable connection. The spring is also able to adjust to changes in environmental conditions such as vibration or heat – something a screw cannot do. Spring clamp screwless connectors are excellent at handling heat, shock and vibration and are widely used in industrial applications as well as domestic wiring. Incorrect installation and poor maintenance can mean severe consequences for screw-type products; these can include loss of connection, burn-out of the connector and, in some cases, an electrical fire. When using a screw-type connector you have to ensure the screw is not over tightened or is not too loose. With the spring clamp screwless connector, this risk is negated.
“Although spring clamp screwless connectors may look more expensive on initial purchase, overall installation cost is considerably lower than the screw-type when taking into account the major time saving benefits they provide.”
WAGO’s spring clamp connectors have an enviable track record for safety and reliability. They are subject to rigorous testing to ensure they meet the highest levels of quality, safety and reliability a well as complying with all the relevant product standards. The quality of the material used in manufacture is far superior to that used in the old-fashioned screw-type connector strips. These are prone to the plastic becoming brittle and the screw head damaging easily. The Nylon material WAGO use is suitable for a wide temperature range and is self-extinguishing in the event of fire (UL 94 Flammability rated V0).
How cost effective are screwless connectors?
Although spring clamp screwless connectors may look more expensive on initial purchase, overall installation cost is considerably lower than the screw-type when taking into account the major time saving benefits they provide. Spring pressure technology can reduce wiring time by around 50% and eliminate costly fault-finding and maintenance visits. These connectors are easy and simple to use. No special tools are required – just strip the conductor and insert. No more fiddling with a cable in one hand and a screwdriver in the other, while balancing on a ladder. No more repetition of tasks when the cable drops out of the screw and you have to start all over again. In the WAGO range, connectors feature a transparent housing so it’s easy to see that the conductor is correctly inserted. All connectors have a conductor strip length guide to eliminate the danger of over or under-stripping the conductor.
Products to suit specific applications
Whilst screw-type connectors may be suitable for all types of conductors, there are screwless products which are specifically designed for solid, solid and stranded or solid, stranded and flexible conductors.
Research shows that, when asked, most electricians who have tried the spring pressure screwless connectors, state they are unlikely to go back to screw-type products. The main reasons given are ease of use, time-saving, reliability and overall cost-effectiveness.