Solar panel add on

Hi, im having the usual problem with having to put kingham on hook up at least once a week to keep batteries topped up. Mines got a ec 500 controller that i believe causes a drain. My amps drop fairly rapidly.  I have vehicle alarm. Im looking for someone with good knowledge on upgrading solar panels with a mptt charge control. Id like it to be able to survive on its own without hook up. Even when travelling and been off grid the amps fall over a few days even when driving every day. Im in bedfordshire area. My last camper was simple. . Hope someone can point me in the right direction as ive a long trip planned after lockdown

What’s the size and age of you leisure battery, had this been left to go flat for any time

first thing check the roof space as to what extra panels you could fit
fitting two leisure batteries as when you have days that the solar charge is very low you need the extra reserve. this is just the start as a lot is down to the space you have

I'd say you need some advice from a similar owner of an EC500 based van who has already travelled along the route you want to take. What's the size of your existing solar panel, what solar controller are you currently using?

FreelanderUK wrote:What’s the size and age of you leisure battery, had this been left to go flat for any time

I have 2 100ah batterries about 3 years ols

Relaxez-Vous wrote:I'd say you need some advice from a similar owner of an EC500 based van who has already travelled along the route you want to take. What's the size of your existing solar panel, what solar controller are you currently using?

 I have an 80w solar and controller is original onegor ec 500

Nickandpaddy wrote:

FreelanderUK wrote:What’s the size and age of you leisure battery, had this been left to go flat for any time

I have 2 100ah batterries about 3 years 

What size panel do you have now and how is it wired ,threw the EC500 or direct to the battery

He well have this wire through this controller that needs to be be unplugged off the p c b and the mppt fitted[You must be registered and logged in to see this link.]

Nick this is worth a read[You must be registered and logged in to see this link.]

As has already been said you need to measure the roof space to see what is available to add extra solar panels , as you already have an 80w panel the easiest route would to be add an extra panel to this to increase your wattage.

If the wires from the panel that’s fitted are not a minimum of 4swg you will need new cables

You will have the hole in the roof already drilled and the route of the wires , you will need a panel of your choice , a new water proof cable gland ( unless you are able to pull new cables threw the original), panel interconnected cables and cables to the regulator ,new regulator ,suitable sealer /adhesive to stick the cable gland to the roof 

You will have to decide if you would like to use a duel Mppt regulator or a battery master to charge the starter battery

either way, any new panel will need to be 'joined' to the existing one in parallel to increase the wattage...there are waterproof MC connectors available to do this externally on the roof, leaving a single cable disappearing through the gland to the regulator. depending on the thickness of the wires you 'may' be able to utilise whats already up there....and already fed into the van through the existing gland. if so, this makes the addition of an extra panel more straightforward.

as suggested, a dual output regulator (like a Votronic Duo) will deliver a constant 1A charge to the starter battery while passing all other available power to the leisure battery. ensure that any MPPT Duo model selected is man enough to cope with the total solar wattage being delivered.

provided that a new set up bypasses the Sargent PSU, as described in Glyne's notes, the losses from this can be avoided and, as such, the 1A charge should easily cope with any small tracker/alarm/immobiliser drain. its the Sargent unit's smothering of low level winter solar output that causes so many drained batteries we read about.

B/B Chris
you said to wire in parallel and is something I do not do
with the weather in the winter you may not get even 12volts from a 20volt panel so will not get any charge. with 2x80w panels and now max 40volts I have been just getting above 12volts giving just over 1amp so still getting some charge with the mist and cloudy days that would not have given me any charge . the other benefit you can increase the volts but not the amps watts in a wire and not need larger cables.

thats true, Glyne....for those who wish to get some bedtime reading, Google 'solar panels - series or parallel' for a rivetting read.

Solar panels connected series or parallel, there are pros and cons. With series if one panel is shaded you wont get much output, with parallel you still will,. On the other hand with series as glyne advocates above, the low light level performance is improved because the charging voltage can more easily reach above voltages at the batteries, so can put in a charge. This over 12 volt  threshold with parallel will only be achieved once the light levels have risen sufficiently higher, either in winter and also in summer at dawn and dusk.

Series will achieve a higher voltage so you'll need to check if your solar controller can handle this. The Votronic Duo Dig range open circuit maximum voltage is 50V, The 80W panels A-S have an open circuit voltage of 22v, so no more than 2 panels in series should be within these Votronics limit.

The Epever DuoRacer solar controllers, the 10A rated controller are 60V, the 20A and 30A are 100V, so a useful choice if you plan to fit several solar panels in series.

When I asked the supplier of solar panels to A-S he said connect in parallel, The Votronic installation manual has parallel showing, so 6 of one 0.5 dozen of the other, you pays you money and make your own choice. I brought the wires from my second solar panel back inside the van so I could have an arrangement when I can switch from series to parallel depending on how much the van was shaded by trees. But can I be bothered.

as it was said on another post if you fit 4 panels you wire 2 and 2
my house has 18 panels but wired 2 x 9

Im going to see what panel i can fit on roof. Im sure my.last solar  panels were in series as mmore volts and mppt utilised this for more amps. What has anyone managed to get on a kingham roof.

Can you do a picture looking down at you roof this will help.if your going to wire in series as I do the panels can be different sizes

How do you post photo on here. Im still looking at what to do. Im looking at in series on panels and maybe a victron controller and battery master for vehicle

what are you wanting to post the photo with

Photo of roof.

I post mine with my iPhone .there is a post that explains what to do with other items as there are different ways as per what you are using

Ok.thanks ill have a read

I fitted a second 80W to my Symbol and combined with the original gives a really nice amount of power both for storage and off grid with a MPPT controller bypassing the EC500.

If you go on photonicuniverse they sell German panels that are smaller than normal but offer the same power.  I fitted this to the back of my Symbol and it squeezed in really nicely.  Not sure on the Kingham roof but worth a look if space is a premium.

Personally I went for parallel fitting.  I'm not re-opening the argument as this is one of those topics where you ask 100 people and get 100 opinions.  I'd recommend doing what I did and do a lot of reading up on the subject and then make a choice.
I feel my choice of parallel was right for me and it works great even throughout winter so I'm happy with that.

Greyhound wrote:I fitted a second 80W to my Symbol and combined with the original gives a really nice amount of power both for storage and off grid with a MPPT controller bypassing the EC500.

If you go on photonicuniverse they sell German panels.............................

Hi Greyhound 
I would like to copy your modification.
Did you connect the cable for your second panel to the Autosleepers fitted connection box on the roof.
Did you have to make any changes to set up inside the van. (connections, wiring or parameters)
Thanks
Richard

Baggiecamper
the solar panel wires from the panel go into the roof through the white box cover and join inside to the sargent wiring that then goes down to your ec500 its not a connection in the box .when you add extra panels I would not recommend putting more power down the cables in the sargent wiring as for the size of the cable more of a problem when wiring in parallel