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Fuse Holder Issue

Hmmm... So I was wondering about some unexpected readings coming from the panel array. It looked like a panel was dropping out randomly, then coming back online a sort period later. Eventually the panel dropped out permanently. 
Below is an example, notice the sudden drop off and flat bottom of the trough (clouds passing tend to be pretty spiky) as well as the consistency of the trough depth.
graph of panel dropping out.

I was thinking a fuse had blown, but it was a bit more interesting than that. A couple of the fuse holders had melted bits on the side?? 
It turns out the cheap fuse holders I got were slightly defective and did not contact the fuses properly, but some bright spark(excuse the pun) had jammed little strips of metal to make the contact.
Unfortunately these bits of metal could not handle the current and heated up and eventually fried.
Defective Fuse Holdershttps://sites.google.com/a/pseudo.net.nz/pseudo/projects/pv-hot-water/fuse-holder-issue/IMG_20150208_100644.jpg?attredirects=0
https://sites.google.com/a/pseudo.net.nz/pseudo/projects/pv-hot-water/fuse-holder-issue/IMG_20150208_100549_1.jpg?attredirects=0

So the panels are offline for now while I order some new Fuse Holders.
On the up side, the strips of metal can't have been good for efficiency and it will be interesting to see if there is a measurable difference with the new Fuse Holders.

So I jury-rigged the old fuse holders to keep the panels going till the new ones show up. I did this by grinding down the end to allow the cap to screw in tightly, making a good contact.
After I made the temporary fix I noticed a significant improvement in efficiency of about 100W. 
Below is a before and after picture.
Before fuse holder fix
Afrer fuse holder fix