Re: Screw terminals vs spring cage

Home Electrical Engineering Forum General Discussion Screw terminals vs spring cage Re: Screw terminals vs spring cage


The “problem” with conventional screw type terminals is that even if properly torqued at installation time, it might loosen, especially whenever there are vibrations (AC power is already a reason for vibrations, I believe, but also on applications with vibrations, like marine, large presses), or significant changes of temperature (motors which are on then off for some time …).

And this loosening problem (I should also mention bad connection at installation time) remains an important risk, which can end-up in down-time and loss of production, or in the worst case may start a fire … This is generally prevented through regular maintenance, either to re-tighten the terminals or thermal imaging, sometimes vibration measurement to check the risk of loosening an thus reduce if needed the time between maintenance campaigns.

When you use cage clamp terminals, in my experience, the huge advantage is that you don’t have to worry anymore because they won’t “loosen”. I believe this can be an advantage even for you as switchboard manufacturer, as it reduces the risks during its on-site usage. And it probably has other advantages of interest for you, like quicker connection, no or less risk of loose connection at assembly time …

I didn’t see and don’t know about any problem related to their usage, so my advice would be: go for it !

Regarding larger cage clamp terminals, I believe it is the same advantages but have less experience.