Optimizing Off-Grid Time with New Lithium Setup - spent £1000 and only one day off grid? Advice needed please

[Langloan]

Got a new lithium set up installed for about £1000

Off grid and have the lights on and watching Netflix via in van wi fi

Should I expect more time left off grid than this

1 day wouldn’t even do a 3 day rally

 

[Jimbohorlicks]

But you need to put something back in as well. Have you got any solar or a b2b.
The one day showing is what you would probably have remaining if you left everything on all day at the same draw down rate.looks like you have only used 6 amps at a draw down rate of 3.4/4 amps per hour.

 

[jonasw19]

total max capacity appears incorrect as you seem to have 2 off 100ah batteries and only 100ah total capacity, Maybe reset capacity to 200ah
jon

 

[DandJ]

I may be being very thick but....wouldn't the system be stating 1d 1h 35m with the current usage? I.E if you had the TV, Netflix/wifi and lights on permanently? Presumably (unless it's chucking it down for days on end) you'd only be using it all for a few hours a day ?

 

[Tombola]

You have 2 batteries showing in the app, and installed, both 100ah each so you have 200ah in all.
you have 97% left in each battery, (194ah) and present current draw = 3.6 4amps (per battery) =7.2 BUT.

what does your telly and light use per hour lets say 4 amps telly, , lights say another amp or 2 , fan for heating if on gas (lets go mad and say 1 amp_) and finally some other random phantom draw (alarm, usb lights, battery master even etc etc) 2 amp
4+2+1+2 =9 ah
200/9 = 22.5 hours from 200 ah batteries

all assumed with no other charge GOING INTO the batteries to offset anything.
Remember the 3.6 you see is per battery

SHORT ANSWER yes the app is right (per battery)

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[Tombola]

I may be being very thick but....wouldn't the system be stating 1d 1h 35m with the current usage? I.E if you had the TV, Netflix/wifi and lights on permanently? Presumably (unless it's chucking it down for days on end) you'd only be using it all for a few hours a day ?

yes

 

[Bessy765]

With respect I was always told the when using two batteries the positive should be on one and the negative on the other to equalise the charge/load. Also the negative resting on the metal case of the Victron unit is not a good idea as althoughnegative could eventualy chafe?

 

[Tombola]

With respect I was always told the when using two batteries the positive should be on one and the negative on the other to equalise the charge/load. Also the negative resting on the metal case of the Victron unit is not a good idea as althoughnegative could eventualy chafe?

Thats right but take another look, thats how it is Bessy765
but yes agreed on the chaffing

 

[Otter Spotter]

As Jumbohorlicks says, your app is showing only a day of power at the level of draw at that very time, if you keep watching the app and switch various items on and off the duration of power will vary. Try switching everything off leave for 15 mins then check your app, then lights on and you will see the time very from 1 day to 5 or 6 days at least, depending on how your set up feeds back into you the battery you may find your batteries will indefinitely

 

[DandJ]

yes

Is that a 'yes' I am being thick or the other?

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[Tombola]

Is that a 'yes' I am being thick or the other?

yes

you are right and not thick, the readout is dynamic pretty much to the second

 

[mitzimad]

the simple question is how long have you been drawing power to lose 3 percent?

 

[Lenny HB]

With respect I was always told the when using two batteries the positive should be on one and the negative on the other to equalise the charge/load. Also the negative resting on the metal case of the Victron unit is not a good idea as althoughnegative could eventualy chafe?

Normally not critical with only two batteries but with high discharge & charge rates of lithium they should be correctly wired.

Several things wrong with that install and it could be dangerous under fault conditions.

Each battery must be fused seperatly as close to the battery as practical. Can't see any fuses in that installation without a fuse on each battery if one battery developed a fault it could take out the other battery. OK the BMS should shut down on the other battery IMO not worth the risk.

The positive connection from each battery should be wired via a fuse to a busbar and the connections to the van taken from the busbar.
Same with the negative connection but without the fuses then the negative connections taken from the busbar.
The cables should all be the same length.

If I'd paid for that install I would not be happy.

 

[St3v3]

What are you running that is pulling a total of 7.2A?

Maybe turn things off and see what that drops to.

 

[tinkertaylor]

You also have insulation damage that looks like it's from overheating

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[Cush]

I am definitely no expert and photographs can be deceptive but I would definitely be checking out that black cable. Either melted plastic or some chewing gum on it
unfortunately the screen shot I took is too large. It’s the black cable running left to right over the blue box in your first picture of your set up. Hope it’s chewy

 

[Lenny HB]

You also have insulation damage that looks like it's from overheating



View attachment 865180

I am definitely no expert and photographs can be deceptive but I would definitely be checking out that black cable. Either melted plastic or some chewing gum on it
unfortunately the screen shot I took is too large. It’s the black cable running left to right over the blue box in your first picture of your set up. Hope it’s chewyView attachment 865182

Missed those when I was just looking on my phone eairler. How can an installer leave cables like. Even if they were cables they hadn't fitted they should have replaced.

I think OP should take it back to the installer and ask them to rewire it correctly but maybe a big risk as they don't appear to have a clue.

 

[Bessy765]

Thats right but take another look, thats how it is Bessy765
but yes agreed on the chaffing

View attachment 865134

Why are there two of the heaviest cables linked to the left hand battery? Not the ones between each battery.
but the ones taking the power to the van.

 

[Bessy765]

I have 2 x 100 amp Transporter batteries and suitable if over spec cabling

 

[Lenny HB]

Why are there two of the heaviest cables linked to the left hand battery? Not the ones between each battery.
but the ones taking the power to the van.

The heavy cable goes to the isolator switch for the inverter, the two smaller I would say are the original wiring they look way undersize for a Motorhome so probably a Brit van as they always use undersize cables.

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[Bessy765]

It is always difficult to point out possible errors when someone has just spent a lot of money on anything but the installer should take a good hard look at this installation and be ashamed, what will secure the batteries if you were to hit a pothole or like I did missed a pedestrian crossing ramp in France with hell of a bump. Surely the main cables via a fuse on both positives to a bus bars would have been a better layout than numerous cables as shown.

 

[Lenny HB]

The batteries may be clamped around the base, you wouldn't see it in that photo that's how Hymer mount their batteries but with that install maybe not.

I agree with what you say when someone has paid for the install but that install is not safe.