Travis's house battery install

[Dunbar]

I suspect the only advantage of 24v is the fact that it takes half the amps for similar watts, so you can use higher gauge cable to carry loads (only really relavemt for longer runs of cable, if you put the Victron 12v to 24v near the bluetti, you lose the advantage completely). I’m sure you’d have to do a study on efficiency of a 12v to 24v boost device vs a 12v inverter, especially if wanting max efficiency w/out the alternator, but seems like it would be a lot simpler to add a 200w inverter to your starting power system to charge the Bluetti through it’s AC port over converting 12v to 24v with the DC to DC.

That makes sense. I guess I was trying to avoid the DC to AC to DC because of the inefficiency of the AC brick adapter. But it would run at near 200 W and I could have higher wattage for any other loads still at 12v. And I could have a higher output inverter for much bigger loads than the Bluetti would pull. So back to emulating @tbisaacs build but smaller within the constraints of keeping both 3rd row seats. Thanks @lx200inAR

 

[Dunbar]

@tbisaacs I'm wondering why you used the isolated Victron Orion rather than the non-isolated unit. From what I am reading it will work but with a chassis ground is not necessary. A boat install would necessitate isolation and full run of ground back to the batter. Had to look in a few deep rear pockets of the interwebs to try to understand which to use. I am finding that the stock 100W inverter is not charging the Bluetti through the AC brick. It appears to fire up but then cuts out so must be overloading the circuit. So getting smart 12v to the back is moving up the priority list. I need a quick solution but want components that will work with a full nice system like the OP's.

 

[sdnative]

@tbisaacs I'm wondering why you used the isolated Victron Orion rather than the non-isolated unit. From what I am reading it will work but with a chassis ground is not necessary. A boat install would necessitate isolation and full run of ground back to the batter. Had to look in a few deep rear pockets of the interwebs to try to understand which to use. I am finding that the stock 100W inverter is not charging the Bluetti through the AC brick. It appears to fire up but then cuts out so must be overloading the circuit. So getting smart 12v to the back is moving up the priority list. I need a quick solution but want components that will work with a full nice system like the OP's.

You can turn an isolated charger into a non-isolated by connecting the input (-) and output (-) together. You cannot convert a non-isolated charger into an isolated one. I used a isolated charger as I wanted the flexibility even though I currently don't use it isolated. I would actually use it isolated if it weren't for a few small DC loads that I only ran one wire to that necessitate using chassis as return.

 

[tbisaacs]

@tbisaacs I'm wondering why you used the isolated Victron Orion rather than the non-isolated unit. From what I am reading it will work but with a chassis ground is not necessary. A boat install would necessitate isolation and full run of ground back to the batter. Had to look in a few deep rear pockets of the interwebs to try to understand which to use. I am finding that the stock 100W inverter is not charging the Bluetti through the AC brick. It appears to fire up but then cuts out so must be overloading the circuit. So getting smart 12v to the back is moving up the priority list. I need a quick solution but want components that will work with a full nice system like the OP's.

No specific reason - either will work. My isolated charger uses a common ground fwiw.

 

[tbisaacs]

You can turn an isolated charger into a non-isolated by connecting the input (-) and output (-) together. You cannot convert a non-isolated charger into an isolated one. I used a isolated charger as I wanted the flexibility even though I currently don't use it isolated. I would actually use it isolated if it weren't for a few small DC loads that I only ran one wire to that necessitate using chassis as return.

View attachment 3107116

Also curious - why would I use one or the other?

 

[sdnative]

You would only need isolated if you wanted to keep your house battery and loads separate from the vehicle battery for whatever reason. Probably more common in a boat installation than vehicle. I was initially planning to keep them separate, but ended up connecting them due to the reason mentioned above.

 

[Dunbar]

This guy has a video about the difference. Hard to find a non-isolated one on Amazon but evidently they are cheaper. Another video I came across discusses the Victron mounting instructions and voltage loss with heat build up. He uses 12v fans blowing up from the bottom through the heat sink. IR video etc. Not too sure how much real world effect there is but will probably mount mine vertical with head space above.

 

[sdnative]

This guy has a video about the difference. Hard to find a non-isolated one on Amazon but evidently they are cheaper. Another video I came across discusses the Victron mounting instructions and voltage loss with heat build up. He uses 12v fans blowing up from the bottom through the heat sink. IR video etc. Not too sure how much real world effect there is but will probably mount mine vertical with head space above.

I believe the heat issue only applies to the 30A version not the 18A, but I could be mistaken.

I like that CPU cooler idea, pretty slick.

 

[tbisaacs]

This guy has a video about the difference. Hard to find a non-isolated one on Amazon but evidently they are cheaper. Another video I came across discusses the Victron mounting instructions and voltage loss with heat build up. He uses 12v fans blowing up from the bottom through the heat sink. IR video etc. Not too sure how much real world effect there is but will probably mount mine vertical with head space above.

Watching this video, non-isolated would have been fine—but yea, didn't even see it as an option on Amazon.

 

[tbisaacs]

This weekend we camped on a friends lake front lawn and really got to see just how much headroom the battery has.

We were parked all of Labor Day weekend, temps in the 90s and fridge at 36 and left to return home with more than 50% capacity remaining.

I was hoping for two days of capacity but I actually think we can stretch to 4.

 

[TeCKis300]

My alternate strategy for charging didn't work out. Going to follow your lead and get a Victron DC-DC Smart Charger.

 

[Dunbar]

I found the non-isolated version on Amazon for $50 less than the isolated one.

 

[tbisaacs]

Last loose end on this projected, literally. I can’t find who suggested it but I took some advice and bought a ferrule crimper and capped the bare wires to and from my Victron. No more fuzzy copper.

 

[TeCKis300]

Last loose end on this projected, literally. I can’t find who suggested it but I took some advice and bought a ferrule crimper and capped the bare wires to and from my Victron. No more fuzzy copper.

View attachment 3111798

Those are nice! May need to add to my kit.

I just played this game yesterday and resorted to solder to set my bare wires. With the OFC fine stranded large gauge wires, something has to be done.

 

[tbisaacs]

After a week or so if usage Im making some changes to cleanup some mistakes.

First, had a comedy of errors this week that lead me to believe that I had killed the battery.

After powering up the fridge and leaving if over night I came out and it was dead. The BMS has hit the low voltage shutoff. This was surprising given how many amp hours I have. The root cause is that the monitor just isn’t calibrated. There are instructions on how to do this and I of course ignored them.

Second and bigger issue is the I couldn’t wake the battery back up even after a lot of driving - I thought maybe it needed to hit a specific voltage to get past the cutoff but nothing worked. I even tried jumping the battery.

I pulled things apart and immediately realized my mistake:

View attachment 3086693


Remember in my first post I had talked about how I was unhappy about jamming 4AWG wire into my Victron which was designed for 10AWG? Well here is the consequence. It spit it out. Charge wasn’t getting back into the battery to wake it up.

My fix was to step down from 4 to 10AWG in the back using a second set of terminals like this:

View attachment 3086705

Now everything is happy and hopefully this install is worry free from here on out.

One more thing. I was slightly worried that stepping down to 10awg between my victron and battery would be a bottleneck but I saw a full 30amps incoming at the shunt. I’m no longer worried about it.

 

[GOLIGHTLY]

View attachment 3079705

Hey man, where you have the Blue Sea panel here, with switch, voltmeter, outlets... Do you recall if there's enough room behind there to install both that panel AND a bank of switches? Thinking of basically mounting one above the other in that same space, just trying to get an idea before I pull drawers out.

 

[tbisaacs]

Hey man, where you have the Blue Sea panel here, with switch, voltmeter, outlets... Do you recall if there's enough room behind there to install both that panel AND a bank of switches? Thinking of basically mounting one above the other in that same space, just trying to get an idea before I pull drawers out.

My truck was the non mark levinson "poverty pack" LX so no subwoofer. Its a huge volume of space. If you have the sub there will likely be less depth available.

 

[GOLIGHTLY]

My truck was the non mark levinson "poverty pack" LX so no subwoofer. Its a huge volume of space. If you have the sub there will likely be less depth available.

Might have a sub for sale here soon then Thanks for the intel

 

[Julian73]

One more thing. I was slightly worried that stepping down to 10awg between my victron and battery would be a bottleneck but I saw a full 30amps incoming at the shunt. I’m no longer worried about it.

View attachment 3111943

Wire size bottlenecks do not block amperage, they create voltage drop that then increases the amperage. ie power needs (wattage) of a device does not change.

 

[tbisaacs]

Wire size bottlenecks do not block amperage, they create voltage drop that then increases the amperage. ie power needs (wattage) of a device does not change.

Yea I’ve gotten slightly smarter since posting. I’m still running this setup and not seeing an incoming voltage drops.