Hank the Tanks Dodgy battery and solar system

[barryd]

Just a thought as a stop gap but I'll not bother. I used it for an hour watching stuff on the laptop. It was still flashing fully charged on the solar controller after.

I think the van has a fail safe for cutting off power to the starter battery if it gets close to the point where it won't start.

I don't think fitting an mppt controller will help. The batteries get full charge with the one we have but it just doesn't last long. I'll just eek it out until we get the Lithium system fitted. We haven't done bad though. Three weeks we have been back on this spot off grid without moving.

 

[merl]

I don't think fitting an mppt controller will help. The batteries get full charge with the one we have but it just doesn't last long.

You previously posted:-

Solar has been crap today as the sun only appeared early on and then about 4pm and it's too low now.

And then you went on to suggest adding a better cab battery and using that for leisure So I assumed you were trying to fix the lack of solar by increasing the battery capacity.
If you're 'managing' WRT battery capacity when it's sunny but not when it's overcast then you need more solar gain. = MPPT/ more panels. If you're not then you need more battery capacity and probably more solar gain too in order to replenish the additional capacity?
You will need an MPPT anyway when you upgrade, you could get and fit that now and it WOULD help on cloudy days.
Careful or we'll have to resort to Trev's idea.

 

[trevskoda]

With the tune of things i think he is just stringing us along, but with no bass for his foundation, dont think i will amplify on this.

 

[barryd]

You previously posted:-

And then you went on to suggest adding a better cab battery and using that for leisure So I assumed you were trying to fix the lack of solar by increasing the battery capacity.
If you're 'managing' WRT battery capacity when it's sunny but not when it's overcast then you need more solar gain. = MPPT/ more panels. If you're not then you need more battery capacity and probably more solar gain too in order to replenish the additional capacity?
You will need an MPPT anyway when you upgrade, you could get and fit that now and it WOULD help on cloudy days.
Careful or we'll have to resort to Trev's idea.

Not quite. The solar on this van charges both the leisure battery and the engine battery. Both are getting fully charged most days. In fact during the day on a sunny day it's great. I can run what I like on the leisure battery as long as I leave it to charge in the afternoon. The issue is with it being late August the time without useful sun is increasing so the battery by midnight has gone from fully charged to 12.2 or 12.1. I just thought taking an hour or two out of the engine battery would elevate that a bit as both would top up the next day.

I'm not messing on with anything else. It's all quoted for and will get done so I'll let the experts sort it out. It was just an idea for now, possibly a daft one.

 

[trevskoda]

My votronic charges both les & starter batts, i have a switch & relay which i use when driving to connect them all up, i can also use this for a emergency start should the engine battery fail, or for jump starting someone else.

 

[Technispark]

Well it's been virtually a week since we arrived off grid here in south Dorset in the new van with the untested solar and battery.

Bit of a development last night. It all went a bit pear shaped. I figured something was up Friday night when after three days of sun the Swift control panel was showing the last level at bed time on the last green light (around 12v). After a sun free miserable day yesterday around 9pm an alarm went off on the panel and the battery appeared dead right round in the red. It had also dropped to Yellow then eventually red on the solar control box. Interestingly though the lights, water pump etc were not dim.

This morning it's showing two green lights around 12.5 but my guess is it's knackered.

Either that or it's just not up to the job. I've already emailed VanBitz in Taunton who from another thread might be a good option to get it sorted.

The plan was to let it charge today and see what happens tonight and tomorrow.

All we run is two laptops, two smart phones, sometimes a TV and sat system, water and led lights.

I reckon it's a 100 or 120w panel, controller and a boggy basic 110 ah battery. Old van had an mppt controller, 100w panel and 120 AGM battery and would be fine this time of year under similar load.

So. What to do?

Pics and more info to follow.

I had a similar problem when we came out of hibernation in the spring. I ‘Re-booted’the system by disconnecting the battery and solar panel , leaving it for 5 minutes and reconnecting