Do peeps puts power wall battery banks down in their basements. In the frozen north, dont they have heated garages? Maybe you would need a sump with a steel lid to put the whole battery bank. At least the fire Dept could fill it with water. All electrical switchgear, inverters inside a steel cabinet. All important cable cutters, gloves and goggle permanently hooked on the wall.
sure take all possible and reasonable precautions. though I think if you double walled the structure with insulation between both walls and an air space separating the two your need for a/c would drop dramatically except for in the desert locations.
close to the same temps in the winter, -5f for me. I heat my batteries and it does not use that much at all, I do not heat the entire structure though, just the batteries. XPS foam battery boxes aluminum spreader plates and the heating pads. no controls what so ever just wire the pads in series spread them across the plates and let ohms law control the output for you. batteries hang out between 15°c and 25°c. no controllers, no logic circuits, raspberry Pi's or ardurino... nothing to monitor other then a temp data logger (which I no longer look at.) I have photos of the battery banks spaced across this forum specifically in ones concerning cold weather use and offgrid use.
Can it be, that the battery was 48V nominal too?
Smoke detectors are to save life, not to prevent fires.
I have a theory that a simple plant spritzer water spray is more than enough to extinguish an arc fire <48V. It takes the heat away and the arc stop ionising.
Be sure to dip your rod in wax first before testing, most hyperbaric welding is in the 300-400amp range maybe at the amperages were using the arc wouldn't sustain but I'd be inclined to think the water will just vaporise but wetting the surrounding area might prevent the arc from spreading.
I meant to extiguish the arc without human intervention.
Agreed this is supposed to be how it is fundamentally achieved. Where it goes wrong is with Big Corp rush towards market dominance (profit) by miniaturisation (in ac terms miniature circuit breakers aka MCBs) and trying to force the fundamentally different current handling into the same sized form factor as could be achieved with ac current.
Yes Ive seen that vid, but what the presenter doesnt mention is the current (I assume its a 1kW fire bar so a nominal 5A drawn (say 5000J) but the voltage applied is 220 V. You wouldnt get this effect at say 22Vdc because the initial arc heat is only 1 percent Joules. Notice the arc extinguishes quickly at ca 5mm separation. However if you increase the current 10X to 50A then you are back to 1000J and may expect a similar effect at 24v level . Must set up my bench. My own Lion fire has demotivated me somewhat.AC vs DC 220V ,,, Some Differences;
I think from your description that is exactly the issue I have been grappling with on another thread. Ultimately it seems lifepo4 batteries required a fuse with a minimum of 20,000 amp interrupt rating, so that the arc cannot continue and the current is effectively cut before fire occurs. The only type of fuse I can find suitable is T type fuse with a DC AIC rating of 20,000A. All other types, Mega fuses, NH or FH fuses etc, are rated for AC interrupt and not DC Therefore your type of fuse was incapable of controlling the short that caused it to fail. Attached is a discussion paper that outlines the issues between AC and DC interrupt rating. It's complicated but worth the read. I am currently in the process of buying T fuses for each of my 280AH 12v batteries. Bloody expensive but I don't see any other option. Especially after seeing your pics and your story. Thank God you and family are alright.
,,, Apparently $10 
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diysolarforum.com
A new MB31 cell has an internal resistance of around 0.18 milliOhms. 3.2V / 0.00018Ohms ~= 18kA.So I am new to this group, couple questions
people keep mentioning that you need for 20k AIC for LIFEp04. Where are people getting this amp rating from, I have seen no links or white papers showing this kind of amperage from normal cells, Most of my reading indicates normal cells in 12/24/48 series configurations are only capable of around 1000A dead short. Parallel strings would all have independent fuses. Most rack enclosures packs, are using a 6k to 10k CHNT AIC breaker such as the eg4 rack battery
Does anyone have some kind of technical document explaining this 20,000 amp rating?
People also keep mentioning T fuses as the savior here, not the enclosure. All my other reading indicates T Fuses by themselves are NOT ignition protected. The link below also indicates that (the enclosure needs to be ignition protected). I see a multitude of photos of bare T Fuses just sitting on bus bars..
Comments from this post also indicate blue sea and Bussmann did not have this tested back in 2020.
Wiring diagram
I am looking for a wiring schematic showing cable gauges for the following set up.... 100Ah 12v LiFePO4 Battery (Hitch mounted on my TT). 2200W Pure Sine Wave Inverter (Mounted inside TT as close to Battery as possible to keep voltage drop < 0.25v?). ANL Fuse 250A? Connect to the Battery +ve...
"NOTE: Class T fuses do not have an ignition protection rating. As near as I can tell, from speaking with Blue Sea Systems, as well as Cooper Bussmann, they have not been specifically tested for this. This only means that they’ve not been tested, not that they would necessarily be unsafe."
Class t fuses have a low melting point fusible link surrounded in silica encased in ceramic so the chance of ignition in quality variants is almost 0 but they can produce heat so when fitted in cheap plastic housing can melt said plastic possibly causing mounting to become loose creating an ark and starting a fire hence the option for quality housing.So I am new to this group, couple questions
people keep mentioning that you need for 20k AIC for LIFEp04. Where are people getting this amp rating from, I have seen no links or white papers showing this kind of amperage from normal cells, Most of my reading indicates normal cells in 12/24/48 series configurations are only capable of around 1000A dead short. Parallel strings would all have independent fuses. Most rack enclosures packs, are using a 6k to 10k CHNT AIC breaker such as the eg4 rack battery
Does anyone have some kind of technical document explaining this 20,000 amp rating?
People also keep mentioning T fuses as the savior here, not the enclosure. All my other reading indicates T Fuses by themselves are NOT ignition protected. The link below also indicates that (the enclosure needs to be ignition protected). I see a multitude of photos of bare T Fuses just sitting on bus bars..
Comments from this post also indicate blue sea and Bussmann did not have this tested back in 2020.
Wiring diagram
I am looking for a wiring schematic showing cable gauges for the following set up.... 100Ah 12v LiFePO4 Battery (Hitch mounted on my TT). 2200W Pure Sine Wave Inverter (Mounted inside TT as close to Battery as possible to keep voltage drop < 0.25v?). ANL Fuse 250A? Connect to the Battery +ve...
"NOTE: Class T fuses do not have an ignition protection rating. As near as I can tell, from speaking with Blue Sea Systems, as well as Cooper Bussmann, they have not been specifically tested for this. This only means that they’ve not been tested, not that they would necessarily be unsafe."
Thanks was struggling with the decimal point.
