Another thread about fuses! But different.

A.Justice

Swears he didn't start that fire.
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I'm building a control cabinet for my security camera system, it's all 12 volt (Yes, I know I should have gone POE, but the cameras I had purchased were all externally 12 volt powered), so to save money I went with those and ran my relatively small house with 12 gauge wire and cat5e to power everything. On the plus side, I can drop DC wires down the wall into an Anderson connector and have 12 volt wherever I need it, no more stupid looking wall warts. All of my routers/ Internet equipment / led strips are powered directly from 12 volts out of the wall without that ac/dc hideous brick. I'm at kind of a holding point as to whether I want to use 2.1 mm barrel jacks, XT connectors, or Anderson power poles as the "outlets". APP's are great, but its a real PITA to get a good solid crimp connection on, and I absolutely abore soldering any of the XT connectors, especially in tight spaces near walls. Anyway, I digress.

The power core of the system is a used Dell server power supply capable of 72 amps at 12 volts, fed into a distribution block with much smaller fuses and circuits per camera. It's a very stable power supply, and it actually accounts for voltage drop under load, not that that load will ever be more than 15 or 20 amps.

My question is this, all of my lithium batteries use class t or equivalent fuses, but this power supply isn't capable of putting out anywhere near what lithium batteries can, so class T is way overkill, both to spec and financially.

I've been looking into MIDI and and ANL for 70a. Both seem to have decent selections of both cheap Chinese quality and nice ones. Given that I'm not familiar with any fuses other than automotive blade and heavy duty lithium, what would be your recommendation for something that is adequate, relatively cheap and easy to replace, and can preferably be purchased at a local store if it blows (I'll buy extras of course). Bonus points for keeping the fuse block small, I'm not exactly low on space, but I don't have a ton of extra real estate in that box. Anything that mounts on a DIN rail is a definite contender, the whole box is DIN setup

Any help would be greatly appreciated, even just a nudge in the right direction of a fuse type I haven't heard of yet.

Thanks guys.
 
IF you want to stay with fuses, we used to use ABB cartridge fuse holders (din mount) that take up to 50A in the mines here (MCB's weren't allowed, had to be fuses lol) but personally, I'd just go a DC rated MCB myself (Element14 has them so worldwide availability)
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Don't work for them or anything, but Element14 (used to be RSS) has practically every type of electrical connector, fuse, breaker or anything else to do with the electrical trade in their 'cattlledog'- I still have one of their paper ones that I use (price are out, but its still good for part numbers,and a hell of a lot easier to search than websites) even though its over 5cm thick (and REALLY thin paper too lol)- bigger than many old metro phonebooks (for those of us old enough to remember such things)
 
Im trying to better understand where the fuse is going.

Are you using a 12v PS to charge lithium batteries that are feeding a blade style fusebox? I would think you would still need that class t for the conduit coming from the batteries since it is the batteries that could be sending all the amps thru the system and not the dell PS.

Or are you putting a fuse inline from the PS to the blade panel?
 
Im trying to better understand where the fuse is going.

Are you using a 12v PS to charge lithium batteries that are feeding a blade style fusebox? I would think you would still need that class t for the conduit coming from the batteries since it is the batteries that could be sending all the amps thru the system and not the dell PS.

Or are you putting a fuse inline from the PS to the blade panel?
No lithium batteries. The fuse would be between the DC power supply unit and the separately fused camera loads.
 
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I've been thinking about a related topic.

12V AGM backup for telecom, etc.
Diodes and Y-cables so wall-wart or battery can feed each device.
Maybe battery needs voltage regulator, if peak charging would be too high.
AC charger for battery, also PV SCC.
PTC fuses for each branch, so if one goes down it doesn't take the others with it.

Given that I'm not familiar with any fuses other than automotive blade and heavy duty lithium, what would be your recommendation for something that is adequate, relatively cheap and easy to replace, and can preferably be purchased at a local store if it blows (I'll buy extras of course).

How about PTC/Poly self-resetting fuses?
 
I use these for the arrays (DC rated MCBs, not AC ones- never use AC breakers on DC, they don't have arc suppression in them)
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