Electrical connector action?

[Tipper]

Hi, I'm having to replace my heating controller due to a fractured connector block. The replacement pcb unit has this connector block fitted for various connections but I can't get the cables to hold. I've got loads of wires to fit as it's under floor heating.
I've tinned the flexes with solder to stiffen them up but as soon as I release pressure on the little square button the cable can be pulled out.
What am I doing wrong? Is there a trick to these connectors or are they just crap?
Thanks

 

[ban-all-sheds]

They have screwdriver slots in them - sure you're not supposed to push & turn?

 

[mikeyd]

Try pushing harder with the screwdriver to see if it latches. The small hole could be to release it (after taking off the pressure by again pushing with the screwdriver)

 

[MarkBarl]

Unless specified I wouldn't tin or ferrule crimp wires for a spring clamp as it limits the surface area that the clamp is acting upon as the wire cannot deform. Try one with un-tinned wire

 

[Tipper]

Thanks.

I found that pushing harder worked! As they are pcb mounted I was reluctant to push too hard but that's all it took. I took the old unit to the bench and prodded and pushed until I was satisfied that I wouldn't damage the new one.

I also found that untinned/ferruled wire end won't get far enough into the clip for it to grip so tinning worked as I could then push them home whilst leaning really hard on the square button and releasing. I suspect the pcb design was based around the electronics design and not the installers needs!

The UFH control valve cables have crimped ferrules but they only just fit and also needed a bit of a push. A bit of a design flaw I think as having to shove hard with both the button and the wire seems a little unfortunate and could cause connector or even pcb damage. No wonder the original installer damaged a clip.

 

[mattylad]

Sounds more like you were not pushing them down far enough, so when you let go they just come out as they have not been gripped.


PCB's are often not designed around the installation.

It's always been a pain to see those that are not, mine all were.

replacement connectors are easy to source and refit.