Thanks for having a nosy at my video on this very little channel. A little bit of understanding makes everything easier. Nowhere near the energy you have in your videos but hopefully it helps some people not worry about freezing LiFePO4.
Like your approach to be pragmatic. One thing keep me wondering though, noticed your self build battery has 24 cells but you still configure them to form a 4S6P to get 12.8V. Did you consider to go to 8S3P 25.6V system or even add 6 more cells and make a 16S(2P) 51.2V system allowing less beafy wiring and allowing cheaper MPPTs while still having same energy stored ?
@WesselVanSluis cheers! Yes i did consider 24v, not 48v. But this was a system that was built up over time. From lead acid in the previous vehicle too bigger acid in this one (440ah) and then eventually the battery upgrade 5 years ago. Build new from scratch now Id consider 48v, although having all panels in parallel is good for shaded parking at 48v Id need 2 or 3 panels in series per string.
Not ideal when power is so limited that time of year. And as per the video, not a problem anyway, I don't want my water tank/pipes/tap to freeze or me, so there is heat for all of that. Also heat is only for high "C" rates, and in my system 1C is 900amps so that would need a HUGE load to heat up.
Hi Kev I needs some advice please. I have 2x 200ah Roamer lithium battery with a MTTP solar. I went to pick up the van this week and the 20amp fuse had blown on the solar. The batteries were -4 and -2. The BMS had kicked in and turned off charging and discharging My question is do I get a heat pad? and did the fuse blow because the BMS was perverting charging.
Not sure on fuse, but batteries will be protected. If they are inside the van and you are usiing it then they will heat up, if you arent using it, or using power they can sit there doing nothing and its absolutely fine (even discharge at -20)
Understand that at low sun conditions shading or low solar string voltage will be low fast and worse max string current will be decreased faster. I also prefer to repurpose the much cheaper "preowned" components and with the 450Wp now being the horm fir new installaties the "previous" generation 250Wp are ( at least in the low countries (Netherlands, Belgium etc) they are sold for about 40Euro/ piece with an age of around 5 yrs..Advantage of these panels in a string of 4 in series their Vmpp together is above 120V DC, which if you combine that with 2 preowned MeanWell powersupplies like SP500-27 (also ar 40 Euro/piece allows you to DIRECTLY feed them from the solar panel string as they (like almost all MeanWell powersupplies DO WORK also on DC. The BMS can on/off the charging using the Remote Control contacts from these powersupplies. 2 of them in parallel charges a 25.6 V (8S) with good sun conditions with 2x18A and if you don t have suncat all same powersupplies work just as well on 120V 60 Hz or 240V 50Hz so a house mains connection (or a small genset) can charge them using 1000W too. Same systems just as usefull for a "48V" system , just put the 2 powersupplies in series (with reverse diodes on output for protection)...And MeanWell products nade in Taiwan is reliable stuff! Working well, versatile and modular (unless you insist to use Victron which can give you beatifull smart functionalityand Dutch quality ( lang leve Nederland!) (but will cost you considerably more ), just for consideration, then these power supplies are your ""MPPT"" ( note the double"" marks , smart cheap is not necesary bad! (and Dutxh are certificaat frugal people, soecially the ones from the province of "Zeeland" whose motto is "geen cent teveel" (= "not a penny more")..
I tend to find, at least with the panels I've used that you get the voltage very quickly, so i have 350w panels, if they are giving 35w they will be at 30v, 350w 32v and its max power point. so they never really drop below charging voltage when giving a meaningful power, still be getting 5w at 15v. So there is no lost power from not having enough panels in series for me. If I was building a house ground mount system then yeah, buy old panels and just use more, however on a van where space is limited, and new panels being only 35-50 cents/pence a watt then the ability to fit say 1000w of new panels vs 600w of old panels in the same space just doesn't make sense. Newer panels have a better watts/M2 than old panels and if space is limited old panels are not good value.
For big rigs you probably are right, but for smaller campervaans like eg a VW T5 or T6 roof width is limiter to about 1.6 m and 250Wp has a length of about that, so 4 of them can can horizontally fit on the roof and at very low sun angles moved (almost) verticallyon the site. And qhen sun really hast short hours a small gen set is the only sotution which require something modifying AC voltage to battery carging voltage...
Yes, but if you can fit less you want even more watts/M2 so again better buying the newest panels rather than old panels already at 80% of the original output and much bigger than similar output panels available new now.. panels the same size as my 5 year old 350w are now 400w 1.7M x 1M but 10 year old panels would be 250w and only 80% of that.
Well Amsterdam has an atitude of 52.3 degr North we are also not close to equator like eg Singapore. But the North Sea and the warm golf stream keeps our wintertemp quite high. Since 1963 we had no "decent" winters with continuous frost longer than 2 weeks...that s why all our older houses have pointy roofs..wiyh nice angles for solar panels..
@Bosco Dog i will do a video on MPPT settings. Not that simple i have summer/winter settings, settings for heatwaves.... and more for balancing time. But 3.4v/cell or below if your battery is full everyday, 3.6v/cell for balancing and somewhere in between for most other times.
"Working around the limitations" I like that...
Thanks for having a nosy at my video on this very little channel. A little bit of understanding makes everything easier.
Nowhere near the energy you have in your videos but hopefully it helps some people not worry about freezing LiFePO4.
Cheers Kev, having replaced our batteries with 800AH of LiFePO4 a year ago at huge expense...this is good learning (every days a school day) 😀
Isn't that the truth? I'm sixty-five and still learning new things every day!
You got me finishing your sentence off out loud at the start, but the version you were gunna say but stopped yourself 😆
Like your approach to be pragmatic. One thing keep me wondering though, noticed your self build battery has 24 cells but you still configure them to form a 4S6P to get 12.8V. Did you consider to go to 8S3P 25.6V system or even add 6 more cells and make a 16S(2P) 51.2V system allowing less beafy wiring and allowing cheaper MPPTs while still having same energy stored ?
@WesselVanSluis cheers!
Yes i did consider 24v, not 48v. But this was a system that was built up over time. From lead acid in the previous vehicle too bigger acid in this one (440ah) and then eventually the battery upgrade 5 years ago. Build new from scratch now Id consider 48v, although having all panels in parallel is good for shaded parking at 48v Id need 2 or 3 panels in series per string.
Discharging will increase the temperature ...switch on a load
Not ideal when power is so limited that time of year. And as per the video, not a problem anyway, I don't want my water tank/pipes/tap to freeze or me, so there is heat for all of that. Also heat is only for high "C" rates, and in my system 1C is 900amps so that would need a HUGE load to heat up.
Hi Kev
I needs some advice please. I have 2x 200ah Roamer lithium battery with a MTTP solar.
I went to pick up the van this week and the 20amp fuse had blown on the solar. The batteries were -4 and -2. The BMS had kicked in and turned off charging and discharging
My question is do I get a heat pad? and did the fuse blow because the BMS was perverting charging.
Not sure on fuse, but batteries will be protected. If they are inside the van and you are usiing it then they will heat up, if you arent using it, or using power they can sit there doing nothing and its absolutely fine (even discharge at -20)
@@KevIsOffGrid cheers.
Understand that at low sun conditions shading or low solar string voltage will be low fast and worse max string current will be decreased faster. I also prefer to repurpose the much cheaper "preowned" components and with the 450Wp now being the horm fir new installaties the "previous" generation 250Wp are ( at least in the low countries (Netherlands, Belgium etc) they are sold for about 40Euro/ piece with an age of around 5 yrs..Advantage of these panels in a string of 4 in series their Vmpp together is above 120V DC, which if you combine that with 2 preowned MeanWell powersupplies like SP500-27 (also ar 40 Euro/piece allows you to DIRECTLY feed them from the solar panel string as they (like almost all MeanWell powersupplies DO WORK also on DC. The BMS can on/off the charging using the Remote Control contacts from these powersupplies. 2 of them in parallel charges a 25.6 V (8S) with good sun conditions with 2x18A and if you don t have suncat all same powersupplies work just as well on 120V 60 Hz or 240V 50Hz so a house mains connection (or a small genset) can charge them using 1000W too. Same systems just as usefull for a "48V" system , just put the 2 powersupplies in series (with reverse diodes on output for protection)...And MeanWell products nade in Taiwan is reliable stuff! Working well, versatile and modular (unless you insist to use Victron which can give you beatifull smart functionalityand Dutch quality ( lang leve Nederland!) (but will cost you considerably more ), just for consideration, then these power supplies are your ""MPPT"" ( note the double"" marks , smart cheap is not necesary bad! (and Dutxh are certificaat frugal people, soecially the ones from the province of "Zeeland" whose motto is "geen cent teveel" (= "not a penny more")..
I tend to find, at least with the panels I've used that you get the voltage very quickly, so i have 350w panels, if they are giving 35w they will be at 30v, 350w 32v and its max power point. so they never really drop below charging voltage when giving a meaningful power, still be getting 5w at 15v. So there is no lost power from not having enough panels in series for me.
If I was building a house ground mount system then yeah, buy old panels and just use more, however on a van where space is limited, and new panels being only 35-50 cents/pence a watt then the ability to fit say 1000w of new panels vs 600w of old panels in the same space just doesn't make sense. Newer panels have a better watts/M2 than old panels and if space is limited old panels are not good value.
For big rigs you probably are right, but for smaller campervaans like eg a VW T5 or T6 roof width is limiter to about 1.6 m and 250Wp has a length of about that, so 4 of them can can horizontally fit on the roof and at very low sun angles moved (almost) verticallyon the site. And qhen sun really hast short hours a small gen set is the only sotution which require something modifying AC voltage to battery carging voltage...
Yes, but if you can fit less you want even more watts/M2 so again better buying the newest panels rather than old panels already at 80% of the original output and much bigger than similar output panels available new now.. panels the same size as my 5 year old 350w are now 400w 1.7M x 1M but 10 year old panels would be 250w and only 80% of that.
And yes i need a genny/mains power for 30% of the year here at 54N
Well Amsterdam has an atitude of 52.3 degr North we are also not close to equator like eg Singapore. But the North Sea and the warm golf stream keeps our wintertemp quite high. Since 1963 we had no "decent" winters with continuous frost longer than 2 weeks...that s why all our older houses have pointy roofs..wiyh nice angles for solar panels..
Got the audio now.
Can you show your controller settings
Which controller and what settings? BMS, solar?
I am using a EPEVER tracer 6415. 40amp. With 4. 12v 100amh chins batteries.. configured 24v series/parallel.
@Bosco Dog i will do a video on MPPT settings. Not that simple i have summer/winter settings, settings for heatwaves.... and more for balancing time.
But 3.4v/cell or below if your battery is full everyday, 3.6v/cell for balancing and somewhere in between for most other times.
Got Audio??
You not hear anything? All seems to be working?
No I don't hear you, I the CC.
Thanks I will figure it out. 😊
I've added CC for the first half of the video - will try and do the other half at some point - sorry, it just takes time.
It's a glitch from y/t ...if you join video to soon or something like that. Just leave youtube & rejoin & it'll be okay buddy
Homeless is rough. Hopefully you have been able to get back up on your feet and moved into a proper place.
I think you have it wrong ... I prefer vanlife and travel. Rent the house out for income ;)
Hope you are enjoying your little fixed box :)