Fitting halfords solar panel to 203 coupe

umblecumbuz

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I wonder if the output would be greater if it had been bonded flush to the rear window?
Although, having had a CLC, the driver's view out of the rear window is very poor anyway.
 
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andrew Slater

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I wonder if the output would be greater if it had been bonded flush to the rear window?
Although, having had a CLC, the driver's view out of the rear window is very poor anyway.
Hi,
Measured outputs on the window and off, and got the exact same reading 12.78v so figured it would do and give me more rear view.
 

LostKiwi

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'93 500SL-32, '01 W210 Estate E240 (RIP), 02 R230 SL500, 04 Smart Roadster Coupe, 11 R350CDi
At 138 ma max i personally wouldnt even bother ... Even in direct sunlight you wont get close to that figure, add some shade and its gone ! It may raise the voltage but the amount of current going into the battery will be neglible ?
Up to 21v is a common voltage for 12v solar panels.
I have 210w of panels at around 21v through a mppt solar charge controler so it converts all 21v to current . cheap charge controlers just block above 14.8v and dump the rest as heat.
On a overcast day it can be as little as 0.5 amps ! On a sunny day i may see around 8 amps.
A 100w panel in the real world will give around 3.5 amps when nice and sunny.
Solar panels should have a diode and nowadays most have one already fitted to the back of the panel because if not when night comes the battery will then feed back to the panel.
A rule of thumb is a panel can be up to 10% of the battery capacity before a charge controler is recomended.
Do you have a multimeter? You could connect it to your solar panel on a sunny day and connect the panel direct to your battery and see how many amps it is really producing.
The SolarFrontier panel I have in France puts out 110v. You treat it with a great deal of respect!
 

Clare Parry

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Mercedes Vito 113CDI Traveliner Long Silver
Hi Andrew, did your solution work out with the solar PV please? I am in a similar position, I need a solution for a large Merc. Vito - it has been a total nightmare for 4 years. Two new Merc batteries, new ignition switch - all fitted by main dealership due to "low Volts." Cruise Control rarely/never works which I really need to to knee. I jump start it regularly (invested £80 in a jump starter). I have never been given any advice about creative options like this Solar one ... Problem: I can not extend trickle charger to the vehicle from any plug. I have no idea if my second new battery is ruined by now. I have the latest readings from local garage who said it was on "very lot volts, that's probably why your Cruise won't work." I could post a key page of that doc., if anyone can help :) :) :(
 

DREAMER NO2

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Andrew ,,so please tell us where you fitted it to in the end and what you connected it up to..I am in two minds weather to get one myself .
 

Kev555

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I find my own Vito unless driven daily which it is, Drains a battery to the point where the van wont start in less than a week. I had considered a solar panel for when I dont drive the van as much at certain times of the year so I'm interested in hearing what solar panel solutions other owners have used and whats successful.
 

Tony Dyson

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The equation for a successful solution will be first of all, a battery that's efficiently working within design parameters, an easy test for this would be to disconnect your battery from the car and put it on an overnight charge, immediately after the charge cycle there should be a 'surface charge' indicated in a voltage test >12.6v, putting the battery under load for a few minutes will mitigate the surface charge very quickly, do this and start with a voltage indicated at a steady12.6v. Leave the battery disconnected for 24 Hrs and retest the voltage at the terminals, a good battery should still be reading 12.6v.

Then measure your vehicle's normal battery drain, dependant on the specifications, age and added toys in your car it will have an expected drain of somewhere between 25 and 85mA, I would expect a lot of toys or additions to read anything in excess of the upper threshold of 85mA! what you don't want to be doing at this stage is to be designing a solar charger big enough to feed an undiagnosed battery parasitic drain!

So to estimate the capacity required of a Solar PV panel to maintain the charge of a battery with a 35mA constant drain in the UK, we need to determine the required rated output of a Solar PV panel in Watts ∴ W = Current draw x charging Voltage 0.035×12.6 = 0.441W, this is a 24/7 demand so to take into consideration Solar PV inefficiencies and the UK,s geolocation with regards to solar availability, a multiplication factor of 5 is required to effectively replenish any identified losses.

∴ A solar panel with a rated output of >2.2W will be needed to maintain a battery with a constant 35mA drain.
 

Rockron

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Anyone contemplating PV solar panel charging of batteries could do worse than searching
the Motorhome forums, it's meat and potatoes stuff these days.

FWIW the habitation area my own setup comprises;
3 X 80W 12v panels in parallel, rated up to 21v output. A 20A MPPT Controller adjusts this
to a programmed 6 stage? automatic managed voltage regime which can hit 14.8v for an
hour once month, this agitates the plates enough so as to desulphate them ie 'condition them'.
This charges 2 X 120A batteries, obviously wired in parallel.
All fairly standard in the M/Home world these days.

Unfortunately engine starting requires 24v, so it's 2X12v batteries in series kept charged up
via 2 X 15W 12v solar panels wired in series and managed by a 5A MPPT controller.
Naturally the 12v and 24v systems are kept seperate... oh yeah! I doubt I'd get an insurance payout
in the event of even a part loss burnnup, let alone a total loss conflagration!
Notably, everything is left permanently connected throughout the year, no worries!
 
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