Fuses...
There does seem to be a small degree of voltage-drop associated with fuses, depending on the type and characteristics of the choice utilized by the selected fusing. In most cases it is not large, but it does depend on the type of fuse used. Certainly not all fuses "are created equal" and that probably can't be stressed enough.
I'd really encourage anyone interested in DC fusing and characteristics to read these small informative articles below I've linked from files saved to my desktop about fusing and various fuse characteristics. All articles ultimately in the end recommend fusing. But see why and which types specifically.
Personally, I eliminated all puny "stock fuses" on all of my amplifiers because I felt and agreed they were rather weak----as provided from the manufacturer. I eliminated them
at the amplifier while at the same time upgrading my supply cable sizes. The amplifiers all get fused on both (+/-) lines
at the battery with very high quality & expensive UL-listed (gold-plated contact) fuses designed for high-demand car audio amplifiers.
Technically in a perfect world we would not need fuses, but it is very much like driving without car insurance where one incident then can spell total disaster. A definite gamble and "roll of the dice" and I personally don't feel comfortable going without some form of insurance like fusing. My decision was to use the best possible quality fuses I could find period, and didn't be a cheap-skate when making selection.
At one time from my experience doing car audio amplifier installations I used the re-settable DC circuit breaker panels in a CB & amp install. They are very convenient to use and just trip instead of burning up fuses. But after reading about the dangers associated with using them I switched back to fusing but increased the quality of the fuses & holders. It would seem they can arc over and weld themselves closed to re-complete the circuit resulting in disaster. These breaker panels are excellent in some applications still I imagine. I did like them.
It's interesting how widely varied so many fuses are from internal resistance, voltage handling (both high & low voltage type-rated fuses),
fuse opening reaction times (critical) and more.
About the reaction times for instance, "note that a 30 A Maxi fuse will take about 3 seconds to open when subjected to a 100 A load! The same fuse will carry 40 A for about 2 minutes! So, there is a time lag between applying an overload, and the fuse opening to protect the wire. Enough to allow harm to a sensititve electronic device."
As a general statement, what are the fuse-type ratings & characteristics "protecting"
your gear ?
Are You Using the Right-Sized Fuse?
by Alan Applegate K0BG & ARRL (3-page PDF File)
http://www.arrl.org/qst/2007/10/applegate.pdf
The DC Wiring Page: Connectors, Fuses and Wire
by Emergency Measures Radio Group ARES
http://www.emrg.ca/dc_wiring.htm
Focusing On Fuses
by John Stiles & Photovoltaic Systems Assistance Center (3-page PDF File)
http://photovoltaics.sandia.g ... cdcrnr.pdf