Need help how to open the connector for the solar cable in the solar concentrator box

[MathiasW]

A bit embarrassing to ask, but I needed to rewire some solar panels to a different regulator and all that was fine, except for the last mile, or rather last inch...

In the picture you see the concentrator box where the wires from the various solar panels get collected and then all fed to the regulator.

My problem is that I cannot see how to insert the red and black solar cable into the grey connectors. 6 cables were done in the past, I need to add two more now. It is a connector that will pinch the solar cable. But I need to open this pinching mechanism first to be able to insert the cable, at which point I fail. I thought inserting a screwdriver in the upper slot should open the bottom slot, but it does not seem to have an effect...

As I do not want to apply excessive force, I was hoping somebody here can give me a clue. Do I need a special tool? Or just apply a screw driver in a smart way? I tried a few things gently, but no success.

Thanks a bunch!

Mathias

[HeywoodJ]

Ahh, those take a special talent

There are a series of square holes, one above each round wire entry hole. Into that square hole you put a small screwdriver of just the right size (the largest you can reasonably fit in the hole is best, as considerable force is required). Then it is a little bit of a guessing game. I am guessing that those blocks require you to push straight in to open the clamp. Once you have it open you shove the wire in its hole and pull out the screwdriver.

The guessing comes in because some of them have you pry up/down rather than press inward, depends on who made the block. For any of them, the force required is substantial, you are trying to overcome a spring loaded clamp that applies the same force to the wire as a screw-down terminal in order to make a good connection.

I really like spring clamp terminals, but in this use case they are a pain, because of the geometry, once you get the screwdriver in place it is blocking access to the wire entry hole underneath. Some designers don't ever think about the poor field person who has to make the last connection. If your fingers are anywhere close to as fat as mine a small pair of needle-nose pliers can be a good friend.

This is not the same terminal, but gives you a reasonable idea of the technology:

https://www.youtube.com/watch?v=CZB0tsT5hNE

[MathiasW]

Thanks! I have done this with a screw driver in the past with other connectors, but this one seems to require very substantial force then. I was a bit hesitant not to break something...

Will give it a go when it is dark again and no voltage is on the solar...

[MathiasW]

So, indeed, I needed to be rather more brutal with the screw driver...

Thanks.

[skipgundlach]

While you're at it, install breaker/s on the line/s so you no longer have to wait for dark to work on it/them, and/or merely get it out of the system for some other reason...

[MathiasW]

Originally Posted by skipgundlach

While you're at it, install breaker/s on the line/s so you no longer have to wait for dark to work on it/them, and/or merely get it out of the system for some other reason...

Yep, thanks, makes a lot of sense!