[MH-list] solar panal
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If you are even a little bit "handy" and have a step ladder or something to give you access to your roof its very easy to do the job yourself.
You need to survey the roof with a tape measure and see what size of panel will fit between any vents or other things already on your roof.
Then check out the prices of the panels that will fit and that are within your budget.
You will need some brackets to hold the panel to the roof and a box with cable glands to take the cables through the roof into the interior.
Inside you need a controller between the panel and the battery as Carol says an MPPT type would be the best. The controller should be rated to take the max current the panel can deliver with spare capacity if you are likely to add another panel later.
You will need some cable and I would say 4mm cable should be the minimum size you should use. Stick the brackets and the cable box to the roof with sikaflex leave a 3mm bead under the brackets and it wont need screwing down as well.
You will need to drill a hole in the roof where you will be placing the cable box usually into an internal cupboard or garage that will allow easy onward access for the cable to the battery compartment. You will need to make sure there is no wiring or other item below the roof at the point you intend to drill. Its easier to run and tack the cable across the roof and straight down to the battery than it is to route it through all your cupboards
The controller should be placed where you can see it if you want to monitor what is going on with the charging.
Wiring is really simple there will be a + and a - from the panel that goes into the controller at the panel input terminals then theres a + and a - from the controller to the battery.
Thats it. Sit back and enjoy the free power.
You can find all the things I mention above on ebay and amazon and lots of other places.
Search Ebay for item 122311434322 and you will see all the brackets and cable entry box and glands that you will need. Search for Solar Panel and you will get lots of different panels to choose from. Some will come as a kit some with cable. Some with a controller but most of them will be PWM types not MPPT.
Flexi panels are very light if weight is a problem but also more expensive. It really comes down to getting the biggest panel for your budget that will fit on your roof. You can have 2 panels wired in parallel where you add up the current each supplies for the total current rating required for your controller.
If you have the panel fitted you will pay a lot more than you need to. I can usually fit a panel in half a day if I have all the parts to hand.
Hope that helps.
On 13/03/2018 08:23, kenny.macdougall@... [motorhome-list] wrote:
I agree with all said here. Just need to make something clear. MPPT controllers give you more useable current than PWM because you can use solar panels with a higher (voltage) output. The 140W panel I have has an possible output of 28volts. It's these extra volts that are 'folded back' into the final 14v or so charging the battery.toggle quoted messageShow quoted text
On 13/03/2018 05:45, Paul Jackson paul.f.jackson@... [motorhome-list] wrote:
a personal website
On 13 March 2018 at 05:45, Paul Jackson paul.f.jackson@... [motorhome-list] <motorhome-list@...> wrote:
Paul an excellent write-up. You forgot only one point that comes to mind.
The controller needs to be as close as possible to the battery.
If the controller is close to the panels and a long distance from the panels, like Loudhams, Nottingham did with mine prior to delivery. then there will be a voltage drop on the long wires.
This voltage will be added to the battery volts and thus reduce the maximum charge possible.