TaliaDPerkins
Senior Member
I am trying for an all electric bus to the greatest degree possible.
I have 6400W of solar, and a 4p16s LiFePo4 battery set @ 304AH/cell, 2 of EG4 6kXp inverters for 220Vac HVAC & general house 120vac, and 3 of 4kW 48vdc nominal (60Vdc limit) to 230VAC for kitchen appliances, backup for the mini split, etc. If every inverter was maxed out in a worst case scenario, I would be pulling close to 970A from the batteries at 50.5Vdc at the combined battery busbar.
I have conceded there is likely weather for which I will have no hot water, no non-frozen water and tanks, and no house heat unless I use propane or diesel, and since I already was getting a diesel coolant heater -- I'll be using that for hydronic floor heat if the mini split can't keep up. Next back up is the diesel air heater -- at the penultimate extremity I would try to run the engine to keep the hydronic heating up. As an ultimate "I don't want to die here tonight", backup, I could rig a hot tent camping stove through a window. Yes, the windows are deleted. Yes, the RV windows are double glazed. Why yes, I plan on visiting Alaska, for a while, and not freezing.
I have avoided propane successfully as a house utility, and have two questions.
Aluminum 500/400MCM power cabling, has any one ever used it? Does a 16ton hydraulic crimper and the dies for such sound like it will get it done to make safe connections? Yes, I know to use Penetrox wherever AL touches Cu. The Al cabling cost is like $600, the Cu cabling cost is like $1700. I am taking a buy once, cry once philosophy to my roving forever home -- but if I can avoid throwing money away I will.
16T Hydraulic Crimping Tool 8 AWG to 600 MCM Battery Cable Crimping Tool 0.87 inch Stroke Hydraulic Lug Crimper Electrical Terminal Crimper with 13 Pairs of Dies
https://www.amazon.com/dp/B0BCFG9BFS?smid=A15RXF8WAZUON9&ref_=chk_typ_imgToDp&th=1
This seems like the correct thing to me. I am asking for a reality check -- for that and for Aluminum cabling generally.
2nd topic. I have sourced fusing for my needs. It's not even expensive. What is turning out to be near impossible to get are 60VDC (or better) rated battery disconnect switches with continuous running current in the range I anticipate, which could well be 300A day to day, and 400A even with no inverter in surge mode if I am cooking and the lights are on and the HVAC pulls in. And since fusing is sized for surge mode, worst case is that a switch may have to interrupt that ~970A @ 50.5Vdc or ~870A @ 55.2Vdc depending on state of charge in a fault event.
Where are are people with 48VDC nominal systems getting components? 16 LiFePo4 cells in a string is 51.2VDC nominally. 100% SoC is 58.4Vdc. Most of the DC vehicle switching stuff I see tops out at 32VDC, or, is not for vehicles and is topping out at 100, 500, or 1kVDC, and items with the latter ratings are large and very $$$.
[Edit: I know I'll edit this, I'll find typos.]
I have 6400W of solar, and a 4p16s LiFePo4 battery set @ 304AH/cell, 2 of EG4 6kXp inverters for 220Vac HVAC & general house 120vac, and 3 of 4kW 48vdc nominal (60Vdc limit) to 230VAC for kitchen appliances, backup for the mini split, etc. If every inverter was maxed out in a worst case scenario, I would be pulling close to 970A from the batteries at 50.5Vdc at the combined battery busbar.
I have conceded there is likely weather for which I will have no hot water, no non-frozen water and tanks, and no house heat unless I use propane or diesel, and since I already was getting a diesel coolant heater -- I'll be using that for hydronic floor heat if the mini split can't keep up. Next back up is the diesel air heater -- at the penultimate extremity I would try to run the engine to keep the hydronic heating up. As an ultimate "I don't want to die here tonight", backup, I could rig a hot tent camping stove through a window. Yes, the windows are deleted. Yes, the RV windows are double glazed. Why yes, I plan on visiting Alaska, for a while, and not freezing.
I have avoided propane successfully as a house utility, and have two questions.
Aluminum 500/400MCM power cabling, has any one ever used it? Does a 16ton hydraulic crimper and the dies for such sound like it will get it done to make safe connections? Yes, I know to use Penetrox wherever AL touches Cu. The Al cabling cost is like $600, the Cu cabling cost is like $1700. I am taking a buy once, cry once philosophy to my roving forever home -- but if I can avoid throwing money away I will.
16T Hydraulic Crimping Tool 8 AWG to 600 MCM Battery Cable Crimping Tool 0.87 inch Stroke Hydraulic Lug Crimper Electrical Terminal Crimper with 13 Pairs of Dies
https://www.amazon.com/dp/B0BCFG9BFS?smid=A15RXF8WAZUON9&ref_=chk_typ_imgToDp&th=1
This seems like the correct thing to me. I am asking for a reality check -- for that and for Aluminum cabling generally.
2nd topic. I have sourced fusing for my needs. It's not even expensive. What is turning out to be near impossible to get are 60VDC (or better) rated battery disconnect switches with continuous running current in the range I anticipate, which could well be 300A day to day, and 400A even with no inverter in surge mode if I am cooking and the lights are on and the HVAC pulls in. And since fusing is sized for surge mode, worst case is that a switch may have to interrupt that ~970A @ 50.5Vdc or ~870A @ 55.2Vdc depending on state of charge in a fault event.
Where are are people with 48VDC nominal systems getting components? 16 LiFePo4 cells in a string is 51.2VDC nominally. 100% SoC is 58.4Vdc. Most of the DC vehicle switching stuff I see tops out at 32VDC, or, is not for vehicles and is topping out at 100, 500, or 1kVDC, and items with the latter ratings are large and very $$$.
[Edit: I know I'll edit this, I'll find typos.]
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