Fusing update from a few pages back. A member
, Ebaugh, took me up on my offer and graciously sent me 10 ANL (inexpensive car stereo quality) fuses
to have fun blowing. Below is basically what I sent to him last night (I added a bit more detail for here).. The bank was four Winston 400Ah cells in a 12V nominal bank configuration. This was done more for curiosity about "AIC" and fuse failing "safely" under the high currents of LFP banks than anything else.
"Sorry for the delay. I blew 8 of those fuses
Three were blown in a dead short situation and five were in a "load" situation using my 500A carbon pile load.
Two of the three fuses failed unsafely and blew the window out of the fuse. These pops were LOUD, like fire cracker loud.. None failed to "open" and none damaged the plastic case, though I did not "closely" examine them.. In a dead short they all blew at below 75A as measured with a Fluke 376 meter using the "inrush" capture feature. In contrast I blew a 60A Blue Sea/Bussmann ANL and it failed at 136.5A which is more than double its rating into a dead short (this is to be expected). A 300A Blue Sea MRBF over loaded "OL" my 1000A Fluke meter. The third cheap
ANL fuse did not blow the window, that I can tell visually without my reading glasses, but I am certain based on the other two that it would meet "ignition protection" requirements.
Using my carbon pile load tester I had these 100A fuses blowing at 200A instantly with no delay, just POP.. The "pops" under a 200A load were barely audible and not anywhere near the viciousness of the fire cracker sound of a dead short. I found this interesting.
I suspect blowing instantly at 200A for a 100A fuse means these are probably not true ANL fuses and are likely closer to an ANN fuse. This makes them not well suited to motor
starting loads like an engine
or thruster where a Cooper
Bussmann/Blue Sea ANL preforms extremely well... A Blue Sea fuse can handle 200% for about 5-8 seconds and not pop instantly, and they do.
In short the "car stereo grade" ANL's are far from the quality of Blue Sea/Cooper Bussmann ANL. While they do tend to fail "safely" (n=5) in a "load" blow, they do NOT fail safely in a dead short (n=3).
None of these ANL's failed to open but two out of three in a dead short failed unsafely blowing the window open. The Blue Sea 60A ANL failed completely safely.
I did capture some video and will try to figure out how to edit the blows together if I can...