This could be interesting

upnorthandpersonal

Administrator
I think I do somewhere. But the gist is that they perform as expected, no damages or visual imperfections. I've been making ground mounts for them. It's winter here now and we barely have any light, but once spring and summer hit I'll have more data. I only installed these near the end of summer here, but as I said, they perform very well and are definitely real 500W panels.
 

upnorthandpersonal

Administrator
What is the overall length of yours? I may have my pads changed to 1" instead of .75" based on your design. Thanks.

It's around 11 cm (4.3 inch) for the short ones to slightly over 12 cm (4.7 inch) for the longer ones - the longer ones to bridge the cells at the end of the pack when you have two rows of cells. I could be slightly off, I don't have the numbers here right now.
 

upnorthandpersonal

Administrator
Pictures of the inside of the MUST EP3000 6kW inverter:

DSC_2333-preview3.jpg

2€ coin for scale:
DSC_2334-preview3.jpg

DSC_2335-preview3.jpg

I've not had time yet to check the electronics in detail, or check the brand of capacitor etc. The board does have a conformal coating, and the build quality seems pretty decent. The thing weighs around 35kg.
 

ArthurEld

Photon Sorcerer
2 Euro coin is .935 inches diameter in case anyone else is wondering.

Thanks for the info and pics. I look forward to hearing how it works out.
 
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Solarfun4jim

Solar seduced :-)
Looking forward to the data that comes out of this project and also the programmability functions of the inverter and charger. (y)
 

DerpsyDoodler

Photon Sorcerer
@ghostwriter66

1) yes, you could take the circular braid and put a lug on it. You probably have to experiment a bit selecting the correct size.

2) yes, no soldering. You take the (annealed) copper pipe, start flattening it in a (hydraulic) vise until it's 'flat' but not closed so you can slide the braid in (the full length of the pipe segment, in this case 25mm). Then compress the pipe segment with the braid. After compression you get a cold weld - internally, it will look like this:
https://diysolarforum.com/threads/this-could-be-interesting.7835/page-5#post-114359
How much pressure do you need for this weld to take place?
 

upnorthandpersonal

Administrator
How much pressure do you need for this weld to take place?

10 (metric) tons should do, 12 perhaps slightly better. A cheap manual hydraulic press should do for best results, for example something like this:

You usually can pick them up quite cheaply from local dealers.

That said, you can get very good results with a heavy duty vise. The very fist ones I made that way years ago without getting a weld, but they are still in use to this day without issues.
 
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DerpsyDoodler

Photon Sorcerer
10 (metric) tons should do, 12 perhaps slightly better. A cheap manual hydraulic press should do for best results, for example something like this:

You usually can pick them up quite cheaply from local dealers.

That said, you can get very good results with a heavy duty vise. The very fist ones I made that way years ago without getting a weld, but they are still in use to this day without issues.
If I am going to do this, I want the cold weld. I can’t justify the purchase of a shop press for this, though (it’s not the money, is lack of space). Any other thoughts or suggestions? Anyone? I have a 12 ton hydraulic crimper. Perhaps I could fabricate a custom die?
 

upnorthandpersonal

Administrator
I have a 12 ton hydraulic crimper. Perhaps I could fabricate a custom die?

Should be feasible. You can also repurpose a jack, something like this:

882ABE61-21D2-4B5B-8165-B9E3ED168B31-e1559156610251.jpeg
 

corporate.joe

Solar Addict
Yes, a big, heavy one to put a lot of pressure on it. Ideally a hydraulic vise.
Would a cheaper hydraulic vise(6-ton) do the trick? Like the one linked. I'm very interested in using braids like this for a 24v mobile system to reduce stress on the battery terminals.


I'm trying to figure out the cost of purchasing them already manufactured, if they are available in needed dimensions, versus buying everything to fabricate them myself. If anyone else would like to add the other uses for hydraulic vises that could sway me to having another tool like this, I'd be happy to hear it.

I imagine that the tinned copper braid would work just as well?
 
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