Should I get a MPPT controller, or B2B or CTEK or......... help?
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Pudsey Bear
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I only did it that way as the mini ZIG panel I got off Ebay, had the car/hab switch so I couldn't think of a better use for it, 
hairydog
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It's best to separate the power supply issues from the power storage issues. I hope you won't mnd if I start wth an analogy.
Think of the electicity as water, so the solar panels and charger are filling supplies, the power load is the taps you run and the batteries are the water tank.
You need to find a way to ensure that the water taken out is not more than the water put in, unless you want the tank to run dry. The size of the tank only alters how long you can manage between top-ups.
Leaving that anology behind, the situation is even worse, because running a water tank low won't harm it. Running a battery like yours low will reduce its capacity by 1% or more every time it happens. Something you want to avoid!
If your solar panels are providing enough power, the batteries will stay well charged, but seemingly that's not the case. So you have three options:
1. Use less power. Forget the inverter and the microwave. Use gas for heating your food. It's cheaper than ruining your batteries.
2. Improve the solar output. Yes, a good MPPT controller (costing about £70) will increase the solar panel output by maybe as much as 30% but 30% more of almost nothing won't help at this time of year. But it will from Spring to Autumn.
3. Find other charging sources. It sounds like you don't have hookup where you store the van, or this wouldn't be an issue. So the easiest aproach would be to take the LBs out one at a time, take it home and charge it for 48 hours. Repeat with each in turn, maybe starting again in a few weeks.
Think of the electicity as water, so the solar panels and charger are filling supplies, the power load is the taps you run and the batteries are the water tank.
You need to find a way to ensure that the water taken out is not more than the water put in, unless you want the tank to run dry. The size of the tank only alters how long you can manage between top-ups.
Leaving that anology behind, the situation is even worse, because running a water tank low won't harm it. Running a battery like yours low will reduce its capacity by 1% or more every time it happens. Something you want to avoid!
If your solar panels are providing enough power, the batteries will stay well charged, but seemingly that's not the case. So you have three options:
1. Use less power. Forget the inverter and the microwave. Use gas for heating your food. It's cheaper than ruining your batteries.
2. Improve the solar output. Yes, a good MPPT controller (costing about £70) will increase the solar panel output by maybe as much as 30% but 30% more of almost nothing won't help at this time of year. But it will from Spring to Autumn.
3. Find other charging sources. It sounds like you don't have hookup where you store the van, or this wouldn't be an issue. So the easiest aproach would be to take the LBs out one at a time, take it home and charge it for 48 hours. Repeat with each in turn, maybe starting again in a few weeks.
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??????
wildebus
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For option 3, there is something to be said to out of season going to a cheap campsite with available hookup once, say, a fortnight and getting a full charge that way? could be less hassle then removing the batteries on a regular basis?
hairydog
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Missing "not". This new laptop is wonderful and its huge trackpad is great, but sometimes it is easy to "lose" a word when typing.
hairydog
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Yes, that might be easier. There is a CL a mile from here where I have left the van for 24 hours to charge up and cycled home (Only cost £5). But now I have extra solar panels in the garden, that's not needed.
SimonM
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I have a hookup available at home where I park my MH when I bother to put it on the drive. But why bother with hookup when I’ve got solar panels to do the job. I think that apart from a bit of a blip a short while ago the panels are probably do8ng their job.
Now I’ve stopped checking the Ring inverter voltmeter and use either my digital voltmeter or another plugin unit I can see 13.5v. But I’ve no idea how well the batteries are being cared for.
Taking onboard suggestions on here and a bit of other research I’ve decided to get a Votronic MPPT along with a Solar Computer so I can properly see what is going on rather than guessing or being prompted by an inaccurate voltmeter.
I am grateful for the input and relish seeing the replies, it’s always good to see stimulating responses, thank you.
Now I’ve stopped checking the Ring inverter voltmeter and use either my digital voltmeter or another plugin unit I can see 13.5v. But I’ve no idea how well the batteries are being cared for.
Taking onboard suggestions on here and a bit of other research I’ve decided to get a Votronic MPPT along with a Solar Computer so I can properly see what is going on rather than guessing or being prompted by an inaccurate voltmeter.
I am grateful for the input and relish seeing the replies, it’s always good to see stimulating responses, thank you.
nabsim
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Thats for a B2B Del, Simon was referring to his solar controller when he mentioned Votronic above, I also went for the Votronic 250 and have 2 x 150W panels going through it. May pop a fuse if I ever end up on the equator and actually get 300W but so far hasn't been a problem all over the UK but will update if it does
I have chosen Votronic because it is a lot less work to install with my EBL and because it is very good gear
SimonM
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Well I’ve ordered it all today from RoadPro, we used to have a trade account with them where I used to work but it went dormant, but I managed to get a little discount to helps things out. I’ll do some pics when I get the time to fit it up. I’ll do it when it’s not raining as I need to get on the roof and cover the panels while I’m wiring them up for safety sake
chas142
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My understanding is that as you have 2 different size solar panels you should really fit a controller that will work with different size panels, MPPT can apparently do that . My system is a dual battery PWM controller, (vehicle and leisure), and for that the panels need to match or you reduce the output of the system to something like 2 x the lowest power pannel. If your looking on ebay there are cheap controllers, and even cheaper copies of cheap controllers, I saw what appeared to be a reasonable cheap MPPT version with a aluminium heat sink as the back plate, the seller of that one stated in the advert why his version was better. I can't talk about CTEK as I have no knowledge but a lot more expensive. I connected my solar partly through the Electroblock, connected my solar front battery output on a main feed going into the Electroblock and picked up the output to the leisure on what was supposed to be the output from the add on Electroblock controller. I did it this way as I wanted to be able to regulate the solar power to front or rear battery as I wanted.
Regarding you microwave, if it's digital with an electronic controller / clock you will need to run it from pure sine wave inverter, if it's the basic twist knob clockwork version you can apparently get away with a modified wave version, perhaps even square wave. I have been looking at mine and the options, I managed to get a 3000watt P.S.W inverter for £75.00, so I am going to use the combination microwave and have crispy baked spuds and pizza. I will fit a second split charge system to power the inverter and if needed upgrade to a larger alternator, cook as I drive.
I have also just purchased a 7 stage charger, it's only 8amps max but gives a pulse charge and various other benefits, apparently. Saying that I also have another pulse battery saver that works on charge and discharge and again the manufactures say it saves your battery from sulphation.
Have a look on utube, lots of info on there about all of these things.
Regarding you microwave, if it's digital with an electronic controller / clock you will need to run it from pure sine wave inverter, if it's the basic twist knob clockwork version you can apparently get away with a modified wave version, perhaps even square wave. I have been looking at mine and the options, I managed to get a 3000watt P.S.W inverter for £75.00, so I am going to use the combination microwave and have crispy baked spuds and pizza. I will fit a second split charge system to power the inverter and if needed upgrade to a larger alternator, cook as I drive.
I have also just purchased a 7 stage charger, it's only 8amps max but gives a pulse charge and various other benefits, apparently. Saying that I also have another pulse battery saver that works on charge and discharge and again the manufactures say it saves your battery from sulphation.
Have a look on utube, lots of info on there about all of these things.
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Pudsey Bear
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No real need to cover them Simon, just make sure at the cables don't touch each other, or any other metal together, the only other thing to remember is too connect the controller to the batteries first, then the panel, and of course select the correct battery type.
SimonM
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Thanks Kev, that will make it a touch easier and dryer for me not having to get up on top.
I gave RoadPro my panel specs and asked them to ensure I was going to get the correct controller, and it was then the same as other advice elsewhere too.
Thankfully my microwave has worked fine for the past 6 years or so using my Ring inverter.
I gave RoadPro my panel specs and asked them to ensure I was going to get the correct controller, and it was then the same as other advice elsewhere too.
Thankfully my microwave has worked fine for the past 6 years or so using my Ring inverter.
Pudsey Bear
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chas142
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It's just a Sainsburys version with a grill built in, will then heat / cook by both when on combination. He is right about the amount of batteries unless you go for a small manual type, at about 500w, even that will knock your batteries down, that's 50amps as a straight conversion, it would be more than that as the inverter isn't 100% efficient. That is why I would only use it with engine running, not sure what my alternator is I suspect 60-80 amps but I can get a higher output, 160amp for about £100 and fit and upgrade system myself. It will be linked into the liesure battery to smooth out the flow rather than use the liesure battery.
hairydog
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Not really. There won't be much power coming off them in rainy weather:.no risk of shock. Of course you should connect the battery before connecting the panels, but there is no safety issue
Having said that, I connect my garden solar controller to four different batteries at different times by simply connecting the Anderson connector to a different one. Never worry about the panels being in sun as I do it. The only thing is that the controller"s clock pauses each time, so after a few swaps it is five minutes slow.
That's an Episolar controller, though. I keep my Votronic as a spare, because the Episolar is better for the job it does here.
Pudsey Bear
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