It may or may not be apparent that we spend a considerable amount of time away in the camper. I would estimate that we are away two months of the year, if not more, and since fitting solar over two years ago ( documented here) , it has made the time in the van a lot more flexible. We seldom used electric hook up (EHU), and this has saved us enough cash to pay for the original installation with money to spare. However, after some unreliability cause as a result of the original batteries failing in the last few weeks, its time to make some decisions about where we go next.
I have been really happy with the original install, and if we had not had any issues I am sure we would have just carried on the way we have been. The limited size of the battery compartment behind the front seats means battery options are very limited. On top of this, any battery that will fit the aperture was never really designed to provide consistent power to devices like fridges etc during lengthy periods away. The more I researched it the more convinced I was that the original leisure batteries could only really last a couple of years in my configuration. Deep cycle batteries are designed for continual usage of persistant charge and drain, but these are always going to be higher, if not longer or wider than the stock compartment would ever allow. So with this in mind, if I was going to push forward with my next generation solar solution, it was inevitable that the batteries were going to have to me stored elsewhere.
Once I got my head round this I felt like my hands had been untied! I started stripping out the contents of the cupboards so I could really get to grips with the space I had available. I soon decided that the small lower cupboard next to the fridge was probably the most suitable location for the batteries, and the cupboard above that would be for the fuse box.
The small lower cupboard had a divider panel in which essentially separated the storage side from some of the consumer electrics ( RCD breaker switch, power socket and EHU and associated cabling and junction box ), so this needed to come out to free up some space.
It soon became apparent that the RCD and some of the cabling would also have to relocated if I wanted to run a two battery setup. Once the cupboard was clear enough to get some measurements we looked online for the largest AGM battery that would fit the space and ordered it.
So I set to fabricating the base plate for the batteries out of a sheet of OSB I had lying around.
I wanted to do the whole install as sympathetically as possible, so drilling holes or applying fixings to anything that was an original component of the van would only be done as a last resort. Making a base plate for the batteries gave me an element of flexibility to be able to use this as a fixing platform for securing the batteries in place. It was cut just big enough to snugly fit in the base of the lower cupboard. From a previous project I had an excessive amount of thick black rubber matting, so I decided to place this on each side to create a non slip base.
This picture shows both the lower cupboard divider and the upper shelf which are going to be put into storage in a safe place in case the process needs to be reversed.
Due to the fact the lower cupboard is going to be filled with batteries, and the installation of them can only be achieved effectively with access via the upper cupboard, placing the shelf back into its location afterwards will not be achievable in one piece. In one piece the shelf has to be dropped in at an angle to the lower cupboard space and juggled up into position. On top of this It will need an additional hole cutting in the shelf to allow access for cabling. So this is my reason for fabricating a new shelf.
I chose to use 5mm plywood. This needed cutting to shape and bonding one on top of the other. Reason for not using 10mm in the first place is that I needed to create a lip that forms a resting point along one edge.
Here it can be seen in place.
And here after the cut is applied and the components are painted.
Next is the relocation of the RCD and fuse box. I used a piece of 8mm plywood board cut to size for the back plate. I used two stainless M8 bolts to act as fixings for the RCD onto the back plane. The fuse box uses two self tapping screws.
After some head scratching i fabricated the rest of the components to build up the casing for the RCD unit.
These were then painted in grey enamel to match the cupboard base.
It can be seen here offered into location. Still some way to go yet though.
So I have the new battery and have pretty much fleshed out locations for all of the components in my system. The original live wiring that goes to the old leisure battery location will need feeding back to the new battery location in the lower cupboard and connected to the battery.
My original solar charge controller was a PWM (Pulse Width Modulation) unit. It had feeds for two batteries and came with a LCD display. However, it is fairly basic in its technology and only really acts as a switch filtering power to the batteries when the panels receive sunlight, and stopping drain at night.
During my recent research into solar controllers I have come to the conclusion that I would probably benefit from moving onto the more expensive MPPT (Maximum Power Point Tracking). The MPPT harnesses the solar energy before sending it to the batteries much more effectively. The increase in power to the batteries can be 30% more efficient if figures are to be believed. Along with this efficiency, they seem to have a lot more intelligence and diagnostics available to draw from this type of solar controller. Monitoring using a smartphone via the installed application gives lots of analytics.
So in the next few days I will be placing an order for the above Victron Energy 100/20 , 20 amp solar charge controller with built in Bluetooth. This can be monitored by a phone app when within Bluetooth range. This will be positioned in the original leisure battery location behind the drivers seat. So I am looking forward to getting the rest of wiring completed ready for our two week break in September. On that note I will conclude for now by saying I will add more to this particular BLOG post as I move forward with the rest of the install to hopefully provide complete a guide to anybody that may be considering going down a similar route.