Adding an extra Solar Panel

Motoroamer

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Any advice please

Our Camper is set up with an 85watt plus a 40watt solar panel with a Morningstar MPPT controller to charge our 200AH of batteries (2 x Yuasa L36-EFB)

Its fine for our needs for most of our camping season but we are planning to extend our season whereby I think we will be a bit short on charging capacity.

I have been given a second hand 245watt panel size 165 x 100cms which is far too big to mount on our van.

Could anyone tell me if I could use this as a free standing additional panel by getting another extra controller for it and clipping it on to the batteries to give an additional extra charge capacity in the cooler months please ? If so could anyone recommend a suitable controller
 

maingate

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On the back of the panel will be the technical details. What is the maximum voltage it can produce. That will be the main factor in whether it can be used on a 12 volt system or not. It may be for a Domestic home installation.
 

Motoroamer

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Thanks Maingate, I can't get to it at the moment as I've just had a knee replacement. I would think it was used on a Domestic home installation. Does that mean it's no good for a van even if batteries were involved in a Domestic installation ?
 

maingate

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If you bought a top quality MPPT solar controller, it could handle the higher voltage output from a domestic solar panel. Something like a Victron controller which seems to handle up to 75 volts DC. This one could do the trick but it is close to its maximum of 220 watts capability. In northern climes I think you would be fine with it.


Victron also do a 100 volt DC version.


There are members on here with more knowledge thsn myself, so you should get more (and better) help. :)
 

wildebus

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You are ok running a panel rated at over the maximum power of the Victron controller. it will just cut off the excess power.
A 245W panel will work well with a 75/15 and on the very rare occasion you get over 220W you'll just loose the old few watts.

but where will you store a panel that size in the van? bit cumbersome?
 

Motoroamer

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Thanks Maingate and Wildebus for your knowledge, time and trouble. I'll get a victron and give it a go, I'm guessing 4mm cable may be OK for a shortish run ?

Yes it is a bit cumbersome but the price was right and it should be ok at the back strapped over the bathroom door whilst travelling. It's only a small van (Transit based) so the space is'nt used much at all whilst travelling. In use I can make up a support and direct it at the sun. My existing set up is just fixed flat on the roof.
 

maingate

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I also carry a freestanding panel as backup when it is poor weather. My support system is as follows. Short prop (Summer). Long prop (Winter). The 2 props were whittled from a fallen branch I found. :LOL:
 

maingate

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wildebus

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Excellent. Thanks Maingate ;) Could you specify the lengths of the specified sticks please ? :LOL:

Any advice on cable size appreciated.

Can anybody recommend these folk please https://lowenergysupermarket.com/product/victron-bluesolar-mppt-charge-controller-75-15/
4mm2 is easily ok for your sized panel.
Controller is nice enough but I would do for the SmartSolar rather than the BlueSolar personally.
You can get it at a better price at Onboard with the forum membership discount.
 

Motoroamer

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Thanks again Maingate........spot on :)

Again, thank you Wildebus, much appreciated, sorry I'm a bit mutton on this stuff, is it the Victron 75/15 Smart you would reccommend. I found this one that seems an even better deal than the Onboard Energy deal with discount https://ebay.us/oBMpiU £96 seems a good deal if its the correct one, though maybe you'd say for a couple of quid it's better to deal with Onboard Energy.
 

wildebus

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Thanks again Maingate........spot on :)

Again, thank you Wildebus, much appreciated, sorry I'm a bit mutton on this stuff, is it the Victron 75/15 Smart you would reccommend. I found this one that seems an even better deal than the Onboard Energy deal with discount https://ebay.us/oBMpiU £96 seems a good deal if its the correct one, though maybe you'd say for a couple of quid it's better to deal with Onboard Energy.
That is the controller I would say to go for :)
Looks like a great price and from a decent seller who is fairly new at least to eBay and with good feedback so sure, give him some love (y) (looks like he has a good selection of kit for sale as well :) )
 

Nabsim

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That is the controller I would say to go for :)
Looks like a great price and from a decent seller who is fairly new at least to eBay and with good feedback so sure, give him some love (y) (looks like he has a good selection of kit for sale as well :) )
I thought it was going to be you when I read that Dave :)
 

wildebus

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I thought it was going to be you when I read that Dave :)
It does sound like me :) but no, not me
(I can't match that price! I think he has lucked into one of the "eBay 20% promo offers" that occasionally gets rolled out - and good luck to him (y) )
 

Motoroamer

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Yes thanks again Wildebus, I've ordered that one from 'nomadicvan' and it is an eBay promotion as you say. I paid 96 and he gets 120. Richard, he sounds a decent chap and as you say, I do too, like to support someone new who is reliable and trying to achieve something.

Is it OK to leave the 'load' connections free as the low voltage disconnect is already catered for in the onboard solar installation ?
 

Stanski

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Hi All,
Just got into the conversation and went to view the Victron option to discover this controller offered in the ebay list


My Unc is coming to see me later this month to have me fit a 120W fold up panel and 2 new leisure batteries to supplement the existing 80w and 1 coach battery he has currently installed.

Dear Wildebus
I have no reason to doubt the controller above for his need but am curious if it would have been suitable for Motorroamer in your opinion.
 

wildebus

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Hi All,
Just got into the conversation and went to view the Victron option to discover this controller offered in the ebay list


My Unc is coming to see me later this month to have me fit a 120W fold up panel and 2 new leisure batteries to supplement the existing 80w and 1 coach battery he has currently installed.

Dear Wildebus
I have no reason to doubt the controller above for his need but am curious if it would have been suitable for Motorroamer in your opinion.
There is generally a price-point where PWM controllers finish and MPPT start. It is typically a fair bit more than £30 and also tend to be larger due to the type of components.

There are also a great deal of listings where a solar controller is misdescribed as an MPPT when it is really a PWM. (most people don't actually have a way to check what they are buying and rely on the honesty/accursacy of the seller so can easily be misled).
For example, compare the image in the listing you have to the image in the listing for this PWM controller .... https://www.ebay.co.uk/itm/12V-24V-...lator-Charge-Controller-CMG-USB/254848419706?

I have on a whim tried a few of these cheap ebay "MPPT" controllers. I don't recall finding one that actually was.
 

Motoroamer

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Yes the controller mentioned by Stanski, although headlined MPPT in the text it specifies PWM so rather confusing there for sure.

I believe that this is a case of.......you get what you pay for, as indicated likely, by wildebus. Try as I may I can neither convince or prove to myself that I'm wealthy, but, I really believe this is a subject where paying for a known quality brand make is most important to avoid disappointment.

I started out early in this field when it was quite new, especially the MPPT. I had a bit of a windfall and lashed out on an expensive Morningstar MPPT controller that was programmeable. That was 15 years ago and it has served me well and still going strong. I'm not sure if many of the cheap chinese models would all match that, but is such a minefield to know which might do so, I'd rather not risk it.

Does anyone know .........Is it OK to leave the 'load' connections free on the Victron 75/15 Smart, using it as an auxilliary set up, with the low voltage disconnect already catered for in the other onboard solar installation please ?
 

wildebus

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Yes the controller mentioned by Stanski, although headlined MPPT in the text it specifies PWM so rather confusing there for sure.

I believe that this is a case of.......you get what you pay for, as indicated likely, by wildebus. Try as I may I can neither convince or prove to myself that I'm wealthy, but, I really believe this is a subject where paying for a known quality brand make is most important to avoid disappointment.

I started out early in this field when it was quite new, especially the MPPT. I had a bit of a windfall and lashed out on an expensive Morningstar MPPT controller that was programmeable. That was 15 years ago and it has served me well and still going strong. I'm not sure if many of the cheap chinese models would all match that, but is such a minefield to know which might do so, I'd rather not risk it.

Does anyone know .........Is it OK to leave the 'load' connections free on the Victron 75/15 Smart, using it as an auxilliary set up, with the low voltage disconnect already catered for in the other onboard solar installation please ?
not sure if I fully understand the question on the load. The load connections can be used for anything you like, within the limits of the current (15A). If you exceed that, the load shuts off, so avoid using it for anything that has a surge output. Or you can just leave it disconnected.

As far as vendors go, I like Victron because the products are mature and proven but also are under continuous improvement (a fairly unusual situation) so you know you are getting something that works and will also get better even after you've bought it.
They are also hassle-free so as a supplier/installer I know it is very unlikely I will need to go back and fix anything (only had one failure to date with a Victron product that meant a product return, and that was just a cross-threaded screw on an MPPT Load Terminal connection on a brand new one).
 
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