Hank the Tanks Dodgy battery and solar system

barryd said:
Thanks but not sure how that would work as presumably the current panel only has one set of wires coming into the current controller. I don't think ill over complicate it at this stage. I think the one Trev linked to had outputs for both but again. Ill see how it performs as is with a second battery.
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You just link the input to the 2nd controller from the 1st and connect your hab battery to the new controller output, then swap the cab battery wires into the old hab battery connection point. Not hard Baz.
 
merl said:
You just link the input to the 2nd controller from the 1st and connect your hab battery to the new controller output, then swap the cab battery wires into the old hab battery connection point. Not hard Baz.
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There would be no need to do anything with the cab battery wires though as they are already connected to the original controller. There are two sets of outputs. Battery 1 and battery 2. I suppose it would be straight forward, I'm just not convinced there would be much benefit and it adds another variable to the system which we are still not that familiar with.
 
barryd said:
There would be no need to do anything with the cab battery wires though as they are already connected to the original controller. There are two sets of outputs. Battery 1 and battery 2.
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You could well be correct with that notion Baz but IF the outputs is designated 'main' and the other is 'subordinate' then if you were using a single battery only then you'd typically connect that to the 'main' output and leave the subordinate unconnected, so that's why I suggested swapping it over👍
Yeh, I get the feeling you're not convinced re going MPPT but your existing PWM really is the weak link in the chain, swapping to MPPT is an easy way to get an extra 20% ish more solar and Trevs favourite Votronic is excellent for sure but I just thought I'd show you a very cheap way of achieving much the same outcome.
 
merl said:
You could well be correct with that notion Baz but IF the outputs is designated 'main' and the other is 'subordinate' then if you were using a single battery only then you'd typically connect that to the 'main' output and leave the subordinate unconnected, so that's why I suggested swapping it over👍
Yeh, I get the feeling you're not convinced re going MPPT but your existing PWM really is the weak link in the chain, swapping to MPPT is an easy way to get an extra 20% ish more solar and Trevs favourite Votronic is excellent for sure but I just thought I'd show you a very cheap way of achieving much the same outcome.
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Im not sure they are. I don't think its that clever. Just battery 1 and battery 2. I guess the cab battery never takes much as its rarely used apart from the time we had the Glastonbury stream linked up to the cab stereo :D. I was always absolutely convinced MPPT was the best when I had my old one that Kev put up earlier with the screen and all the info on it. I loved it. This one though charges pretty quick though and seemed on a par with my old one but the main issue was holding onto that power when there was no solar. Maybe an MPPT might have made a difference then I dont know. If I was going to change it I would rather get one that just charged both batteries rather than stick two up there.

I googled it and AI Google came up with this.

No, MPPT controllers are not always better than PWM controllers. Both Maximum Power Point Tracking (MPPT) and Pulse-Width Modulation (PWM) controllers are effective at charging batteries and preventing damage, but they work best in different conditions. When choosing between the two, you should consider factors like:


  • System size
    MPPT controllers are better for larger solar systems, while PWM controllers are better for smaller systems.


  • Climate
    PWM controllers work best in strong sunshine, while MPPT controllers can provide more power in colder temperatures.


  • Budget
    MPPT controllers are generally more expensive than PWM controllers.


  • System complexity
    The complexity of your system and any extra features you need can help determine which controller is best.
 
barryd said:
Im not sure they are. I don't think its that clever. Just battery 1 and battery 2. I guess the cab battery never takes much as its rarely used apart from the time we had the Glastonbury stream linked up to the cab stereo :D. I was always absolutely convinced MPPT was the best when I had my old one that Kev put up earlier with the screen and all the info on it. I loved it. This one though charges pretty quick though and seemed on a par with my old one but the main issue was holding onto that power when there was no solar. Maybe an MPPT might have made a difference then I dont know. If I was going to change it I would rather get one that just charged both batteries rather than stick two up there.

I googled it and AI Google came up with this.

No, MPPT controllers are not always better than PWM controllers. Both Maximum Power Point Tracking (MPPT) and Pulse-Width Modulation (PWM) controllers are effective at charging batteries and preventing damage, but they work best in different conditions. When choosing between the two, you should consider factors like:


  • System size
    MPPT controllers are better for larger solar systems, while PWM controllers are better for smaller systems.


  • Climate
    PWM controllers work best in strong sunshine, while MPPT controllers can provide more power in colder temperatures.


  • Budget
    MPPT controllers are generally more expensive than PWM controllers.


  • System complexity
    The complexity of your system and any extra features you need can help determine which controller is best.
Click to expand...
But the pwm dont pulse charge to clean the battery plates, plus you get more amps as it uses all the 19v condensed down where as the pwm only grabs 14.4 from the panels, the rest is wasted, you require a slap round the ears. 😜 😂
 
Nabsim said:
I helped the sparks rewiring some of the control panel on one of the asphalt plants after a fire. Multi core cables with varying amounts up to around 50 individual cables in each. Every cable in the panel was white on the control side lol

luckily they did have numbers on the cables but was fiddly
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Pretty standard really, it's when the numbers have worn off it gets more interesting on a rewire, though if you can find one good numbered one then the numbers increase as they go round.
IMG_20170117_140233.jpg
 
barryd said:
Im not sure they are. I don't think its that clever. Just battery 1 and battery 2. I guess the cab battery never takes much as its rarely used apart from the time we had the Glastonbury stream linked up to the cab stereo :D. I was always absolutely convinced MPPT was the best when I had my old one that Kev put up earlier with the screen and all the info on it. I loved it. This one though charges pretty quick though and seemed on a par with my old one but the main issue was holding onto that power when there was no solar. Maybe an MPPT might have made a difference then I dont know. If I was going to change it I would rather get one that just charged both batteries rather than stick two up there.

I googled it and AI Google came up with this.

No, MPPT controllers are not always better than PWM controllers. Both Maximum Power Point Tracking (MPPT) and Pulse-Width Modulation (PWM) controllers are effective at charging batteries and preventing damage, but they work best in different conditions. When choosing between the two, you should consider factors like:


  • System size
    MPPT controllers are better for larger solar systems, while PWM controllers are better for smaller systems.


  • Climate
    PWM controllers work best in strong sunshine, while MPPT controllers can provide more power in colder temperatures.


  • Budget
    MPPT controllers are generally more expensive than PWM controllers.


  • System complexity
    The complexity of your system and any extra features you need can help determine which controller is best.
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Well this AI for ya, only the bit about budget is correct, every thing else completely wrong 😡.
Just consider a MPPT as a car with a gearbox and an PWM as a car with just 1 gear. Only at one certain point when both torque and rpm are correct for conditions will the fixed gear be perfect and will out perform the gearbox car due to losses but in EVERY other state the gearbox car will win.
The only time PWM controller will out perform a MPPT is in when the voltage input/ output and current are exactly as required, every other point in time MPPT win because it has a constantly variable 'electronic gearbox' and is ALWAYS hunting to find the maximum power point. MPPT=maximum power point tracking.
 
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merl said:
What's that Julian, arse end of a multi pole multi way rotary switch?
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No. Valve actuator controller (Rotork & Auma) used in big pipelines petrochem, oil rigs, nuke power stations, waterways, ships and £$%^ works! ....... I installed them on all these sites. Later on the multicore cabling moved on to 3 wire data highway bus systems.
 
Our old style Aircon was 12 core plus ...

Now down to 4 via Thyristor control circuits ...

Less cables install wise

BUT can make fault finding rather more difficult
 
merl said:
Well this AI for ya, only the bit about budget is correct, every thing else completely wrong 😡.
Just consider a MPPT as a car with a gearbox and an PWM as a car with just 1 gear. Only at one certain point when both torque and rpm are correct for conditions will the fixed gear be perfect and will out perform the gearbox car due to losses but in EVERY other state the gearbox car will win.
The only time PWM controller will out perform a MPPT is in when the voltage input/ output and current are exactly as required, every other point in time MPPT win because it has a constantly variable 'electronic gearbox' and is ALWAYS hunting to find the maximum power point. MPPT=maximum power point tracking.
Click to expand...

There are a few around with dual charging.

This one is only 10amps though.

www.12voltplanet.co.uk

Photonic Universe DuoRacer Dual Output MPPT Solar Charge Controller - 10A 12V/24V - 60V Input

Dual battery 10A MPPT solar controller ideal for maintaining a starter battery on campervans, motorhomes & boats. Suits all battery types. 12V & 24V systems.
www.12voltplanet.co.uk
 
barryd said:
There are a few around with dual charging.

This one is only 10amps though.

www.12voltplanet.co.uk

Photonic Universe DuoRacer Dual Output MPPT Solar Charge Controller - 10A 12V/24V - 60V Input

Dual battery 10A MPPT solar controller ideal for maintaining a starter battery on campervans, motorhomes & boats. Suits all battery types. 12V & 24V systems.
www.12voltplanet.co.uk
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I would be looking more than 10 amps, i bought a votronic 250w and now wish i had bought the 350 and add another panel.
 
trevskoda said:
I would be looking more than 10 amps, i bought a votronic 250w and now wish i had bought the 350 and add another panel.
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Yes I agree. It would do for the current panel and a second battery but it could be that I might install a second 120w panel as well. If I decide to go down that route it would be better to get a Victron system put in of the type Off Grid Power solutions use so in the event it all going titties up and I end up with a Lithium system none of it is redundant. Well the two 120ah batteries will be but Im not bothered about that. We can hold an auction for them on here. :D The last one is lighting up Julians fish pond I believe.
 
Cannot believe nearly 500 posts on something which is really straight forward.

Lead batteries are yesterday’s batteries soon all vans will come with lithium and not before time. Right now all of the large manufacturers are trying to rip folk off with overpriced lithium systems as options, but eventually one will break ranks and lithium will completely replace lead.
That takes care of batteries.
Now what powers them and controls them is paramount.
Don’t buy a cheap inefficient PWM controller, get your hands on a MPPT, and don’t buy one just big enough to handle your solar array, get one that will handle something a bit bigger, and preferably Victron. I have 330w of solar, but have managed 400w in summer since fitting a larger solar controller.
As for fitting a second 120w panel, I would fit this and even more if your roof takes it.
Panels are cheap as chips and fitting additional panels is child’s play.
Also make sure your mains charger has a lithium setting, yes you can use AGM but one with a proper lithium setting is way better.
When you have done all of this Barry you will be more self sufficient and less reliant on CLs or campsites.
One last thing, if the budget can handle it, and you have at least 200AH of lithium think about a Victron inverter, I got David (Wildebus) to fit a 1200w one under my seat, and it’s a game changer.

This is my roof Barry, if I could squeeze more on I would.

IMG_7235.jpeg
 
Fisherman said:
Cannot believe nearly 500 posts on something which is really straight forward.

Lead batteries are yesterday’s batteries soon all vans will come with lithium and not before time. Right now all of the large manufacturers are trying to rip folk off with overpriced lithium systems as options, but eventually one will break ranks and lithium will completely replace lead.
That takes care of batteries.
Now what powers them and controls them is paramount.
Don’t buy a cheap inefficient PWM controller, get your hands on a MPPT, and don’t buy one just big enough to handle your solar array, get one that will handle something a bit bigger, and preferably Victron. I have 330w of solar, but have managed 400w in summer since fitting a larger solar controller.
As for fitting a second 120w panel, I would fit this and even more if your roof takes it.
Panels are cheap as chips and fitting additional panels is child’s play.
Also make sure your mains charger has a lithium setting, yes you can use AGM but one with a proper lithium setting is way better.
When you have done all of this Barry you will be more self sufficient and less reliant on CLs or campsites.
One last thing, if the budget can handle it, and you have at least 200AH of lithium think about a Victron inverter, I got David (Wildebus) to fit a 1200w one under my seat, and it’s a game changer.

This is my roof Barry, if I could squeeze more on I would.

View attachment 137411
Click to expand...

Don't know if you read the whole thread Bill but you are preaching to the converted. I agree, Lithium is the way to go, I have no doubt about that but by your own admission in your post you say "Right now all of the large manufacturers are trying to rip folk off with overpriced lithium systems as options". The difference for me is shelling out "right now" the neck end of £3k or £120 to maybe (for now) improve a current system to make it viable for next years touring. I questioned it because I had time to think. Do I need an all singing all dancing lithium system "right now". I don't really. We weren't far off having enough power last year and did indeed manage several weeks in Salcombe off grid without moving the van. Its not childs play for me. I can't fit any of this stuff myself if for no other reason than I can't get up on the roof of the van for a kick off.

There is already a good controller and panel in place, its just not quite good enough. Yet. Im happy though to change the controller providing it does what the current one does which also charges the engine battery and as long as down the line when or if I do go Lithium its not redundant. Sadly there is no middle ground. You can't say, ill just have a medium priced Lithium and solar system please and get some dodgy local bloke in a shed to do it for £30 an hour. If I am getting it done I want the best system and the best people to fit it but I just don't think I need it yet.
 
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