Can you use Wago lever connectors with feruled wires?

Question

Do Wago connectors work well with ferules? Does the manufacturer support such use? Are there any pros to using a ferule with Wago connector instead of just naked wires?

Answer 1

The instructions say strip and insert wires. Ferrules are not called out. If not following the manufacturer’s instructions you are not using them in a listed way.

Answer 2

If you're talking about the Wago 221 with levers, the manufacturer's instructions and datasheet say no ferrules are necessary. There doesn't seem to be any pros or cons to using ferrules. I sure wouldn't bother removing a ferrule if there was one at the end of the wire, but adding one is a waste of time. Just twist the strands and make sure there isn't a stray strand poking out waiting to make a short.

Wago's PCB connectors explicitly require ferrules for stranded wire. In this case it makes sense because wires are pre-cut, stripped and ferruled by machines: having the factory worker manually strip and twist the wires before inserting them and check for stray strands would be a waste of time and an unnecessary failure risk.

It is possible to stick two thin wires in the same hole on a Wago 221. That's not listed and not recommended. If the wires are solid or they have ferrules, the thicker one will hold the clamp open and the slimmer wire may look like it's secured, but it will soon pull out.

If you're talking about the Wago 2273 leaf spring terminals without levers, then these are only compatible with solid core wires. So you can't use stranded wires, even with a ferrule. In the event you manage to stick a wire with ferrule in the wago, you'll probably manage to push it half way in, but the indents left by the crimping tool on the ferrule will catch on the leaf spring and it will stay stuck there forever, can't push it in, can't pull it out. Also a big adantage of wago 2273 is the wires can turn inside the terminal which really helps when squeezing all the wires inside a junction box, and that can't happen with a ferrule. It's definitely not listed for use with stranded wires, no matter what's on the tip, so a definite no.

If the wires are thin, especially if you use them to splice phone wires, there's another problem: the hole is too large so there is no strain relief and the wires wiggle too much, so they can break. For these thin wires it's much better to use the proper connectors for phone lines, which have smaller holes that provide strain relief and hold the wire properly.