Modification : Fitting a custom electrical panel
When we bought our camper it was already almost 20 years old. The fridge blew the truck fuse if you tried to run it on 12v, the converter produced 17v DC output that was incredibly noisy, and itself hummed and got hot, the battery was shot, the wire to the truck alternator was far too thin and the charging off AC hook-up was via a budget brand battery charger which boiled batteries dry.
Clearly this was a situation that I could not endure for long and bit by bit I have been tackling these problems.
The fridge failed altogether and was replaced with a compressor fridge.
The roof had to be replaced and along with that the opportunity to add solar power:
Initially, not wanting to splash out a lot of cash until I was happy with the way it worked, I bought the cheapo solar controller (with its amusing translated-badly-from-Chinese instructions):
This worked pretty well.
Here it is fitted, but it also shows two other components that need tackling - the malfunctioning converter (not actually used, but not isolated since all the electrics go through it) and the offending budget brand battery charger:
The brown cylinder was a make-shift isolator - I realised that during daylight hours there was no way of isolating the voltage from the solar panels, so this was a battery isolator fitted to the cap of a plastic jar that used to contain hot chocolate drink powder.
Moving on to the battery bay (under the step up to the overcab area) the electrics from the truck came into this disaster of a box:
Further more the battery was a spaghetti of poorly connected wires powering all manor of things (not a fuse in sight). The battery itself, to clear the water tank drain valve, was balanced precariously on a couple of differently sized pieces of wood - held down only with its own weight. No vent for battery gasses was installed.
The solar panels had improved themselves but with space for only one battery I wanted to optimise the charging of that battery. The wiring run from the truck alternator was pretty long too. The solution last August was to purchase a CTEK D250S Dual DC-to-DC battery charger - this takes inputs from the alternator and the solar panels (replacing the cheap Chinese solar controller) and uses MPPT (max power point tracker) technology and a multi-stage charging program to trade off amps versus volts to give the optimum charge possible from both combined voltage sources - or that is the theory at least:
Another benefit is that you take out the relay between the truck battery and the camper battery (the D250 handles that function) - and if the D250 decides the camper battery is full it will redirect charge back to the truck battery to top that up too.
Over the winter I worked out what I needed from a replacement charging panel. This was my list of requirements:
Obtaining the various components required took many hours on eBay. There are so many components available, but finding the exact one that will work (e.g. battery isolators that are flush mounted and covered) took ages.
Always one to re-use spare stuff in my garage I found a piece of 6mm marine ply left over from the roof rebuild (actually a bit cut out to make way for the escape hatch). I succeeded in buying circular components for the most part, but some were unfortunately rectangular and required a lot of work with the chisel and sand paper to cut out.
Here are the various components test fitted:
I found some left over antique-pine colored floor varnish and use that to coat the panel, and printed labels with a Dymo label printer (the modern type IT departments use, not the old ones that press letters into colored plastic strip that you had as a child - I may be cheap, but I'm not that cheap).
Everything else now had to wait until we had a period when the camper would be unused. That period came after New Year this year when we took the camper off the truck and I could settle down to the longer-than-I-expected task of wiring this new panel in.
The first step was to hunt around for the wiring diagram I had prepared - I tried finding some software to do a neat job of this, but I didn't fancy paying for a package that would only be used once, and all the downloadable ones seemed to prevent you from saving the diagram you had painstakingly drawn:
The camper was then transformed into a little workshop:
The first real hands-on step was to remove the battery and do something about the lack of fuses - having un-fused high-amperage cable snaking around the camper didn't make me feel comfortable:
The removed battery revealed the battery bay - you can see the drain valve that the pieces of wood kept the battery from fouling:
I took one of the two pieces of wood and sawed it into 4 with the circular saw, then located yet another spare piece of roof marine-ply and cut it to make a little platform to clear the valve. I screwed the wood to the floor from underneath the camper, then screwed the plywood to the 4 pieces of wood from above:
To tackle the lack of vent pipe I found an old piece of plastic piping and part of a high pressure air fitting that just fitted into the vent hole in the battery. I jubilee clipped the two together:
The battery could then be fitted in place and held there using an old mini-ratchet-strap handle with an off-cut of webbing taken around the battery and both ends fed into the ratchet strap spool - seems to work well (and again cost nothing):
Now the evil converter could be removed. Stupidly I failed to make a note of the wire colors, and only later did I realise I couldn't 100% guarantee that green was +ve. Though looking at this picture later showed green was indeed connected to the blue +12v output from the converter:
When built Shadow Cruiser had labelled many of the wires - with Biro on masking tape - not a particularly long-lived, but luckily most were still in place, so I was able to re-label them in indelible ink on plastic table-ties - the type with little tags on the end for writing on.
So with all the wires labelled I could get out the wire cutters - no turning back now :E
I had carefully measured the cut-out the converter was in and used that to specify the dimensions I had available in the new panel to fit components into. Of course, to measure this last August I just slipped the converter out an inch and measured the top and side of the hole. What I didn't see because I hadn't remove the pane entirely was the the front edge of the hole was angled. So when I offered the new panel up it wouldn't fit in :S
The quickest solution was to take the hole-saw and use it in a way its instructions probably explicitly forbid for safety reasons - that is using it like a sort of aggressively serrated angle-grinder to trim the offending timber, hoping not to trim any important electrics or indeed body parts in the process:
I decided that first off I needed to tackle the 240v AC wires. These are solid copper cores so have to be twisted into place. Plus I wanted to be able to wire them into place out of the way to achieve a degree of separation from the 12v electrics. The area under the wardrobe (behind where the converter used to be) was now a mass of jumbled wires, so I suspended the 12v wires from the coat hangers at the top of the wardrobe to give me room to work:
First I screwed the DC-to-DC converter into place. Then screwed a terminal block into place behind it for the 240v and fitted the wires between that and the control panel - with the 12v wires hanging out of the way it looks quite neat:
With the 240v wired I could cross my fingers and switch it on, check that the indicator light illuminated, and that the power sockets and fridge were then live - yep, all working. I then unplugged the hook-up again to avoid any nasty accidents while working in that area.
Next was the high-amperage part of the circuit. Again, these are awkward because they are thick cables (16mm sq). This involved the cables from the battery to the isolator, solar through another in-line fuse to its isolator, isolators to D250S and another distribution block (this one dedicated to 12v) and charging output from the D250S to the distribution block.
Next I completed the wiring of the control panel - wiring in all the smaller 12v wires - this was quite a lot of work:
This left a pair of wires I couldn't identify. I recalled they were connected to another wire from the truck that I had previously labelled as "not connected". I tried to trace the wires - the went to the back of the camper, but to no avail. I therefore terminated them and coiled them neatly out of the way. Then I found another matching pair of wires, this time coming from the front of the camper. Again they had the same shade of green (different from the green of all the other internal wires). It suddenly occurred to me what these green wires heading for the top front and top rear of the camper were - clearance lights! Of course when I tested the wire it was dead - it would only have been live when the truck lights were on. So I had to re-wire these.
The new panel could then be screwed in place and the wires tied together using cable ties into neat-ish bundles, designed to allow the panel to be removed or other components to be moved:
The last thing I wired in was the -ve 12v wires. I cable-tied them all together so I could then trim them to the correct length, and then wired them into the 12v terminal block.
I then carefully tested all the electrics - hooray - everything worked first time - no bangs, no flashes, no nasty burning insulation smells:
I'm pleased with the outcome - it was a lot more work than I expected, but I am really glad the camper is usable again. I hate having things in pieces so I can't use them.
Steve.
Clearly this was a situation that I could not endure for long and bit by bit I have been tackling these problems.
The fridge failed altogether and was replaced with a compressor fridge.
The roof had to be replaced and along with that the opportunity to add solar power:
Initially, not wanting to splash out a lot of cash until I was happy with the way it worked, I bought the cheapo solar controller (with its amusing translated-badly-from-Chinese instructions):
This worked pretty well.
Here it is fitted, but it also shows two other components that need tackling - the malfunctioning converter (not actually used, but not isolated since all the electrics go through it) and the offending budget brand battery charger:
The brown cylinder was a make-shift isolator - I realised that during daylight hours there was no way of isolating the voltage from the solar panels, so this was a battery isolator fitted to the cap of a plastic jar that used to contain hot chocolate drink powder.
Moving on to the battery bay (under the step up to the overcab area) the electrics from the truck came into this disaster of a box:
Further more the battery was a spaghetti of poorly connected wires powering all manor of things (not a fuse in sight). The battery itself, to clear the water tank drain valve, was balanced precariously on a couple of differently sized pieces of wood - held down only with its own weight. No vent for battery gasses was installed.
The solar panels had improved themselves but with space for only one battery I wanted to optimise the charging of that battery. The wiring run from the truck alternator was pretty long too. The solution last August was to purchase a CTEK D250S Dual DC-to-DC battery charger - this takes inputs from the alternator and the solar panels (replacing the cheap Chinese solar controller) and uses MPPT (max power point tracker) technology and a multi-stage charging program to trade off amps versus volts to give the optimum charge possible from both combined voltage sources - or that is the theory at least:
Another benefit is that you take out the relay between the truck battery and the camper battery (the D250 handles that function) - and if the D250 decides the camper battery is full it will redirect charge back to the truck battery to top that up too.
Over the winter I worked out what I needed from a replacement charging panel. This was my list of requirements:
- A digital volt / ammeter so I could monitor battery state and how much current is going into or coming out of the battery.
- An isolator so I could easily isolate the input from the solar panels
- Another isolator to isolate the battery
- Yet another isolator to allow me to turn off all AC hook-up power without having to go out in the rain and wrestle with 240v electric cables
- Fuses
- A set of switches for future use, e.g. for controlling external flood lights
- Another accessory socket
Obtaining the various components required took many hours on eBay. There are so many components available, but finding the exact one that will work (e.g. battery isolators that are flush mounted and covered) took ages.
Always one to re-use spare stuff in my garage I found a piece of 6mm marine ply left over from the roof rebuild (actually a bit cut out to make way for the escape hatch). I succeeded in buying circular components for the most part, but some were unfortunately rectangular and required a lot of work with the chisel and sand paper to cut out.
Here are the various components test fitted:
I found some left over antique-pine colored floor varnish and use that to coat the panel, and printed labels with a Dymo label printer (the modern type IT departments use, not the old ones that press letters into colored plastic strip that you had as a child - I may be cheap, but I'm not that cheap).
Everything else now had to wait until we had a period when the camper would be unused. That period came after New Year this year when we took the camper off the truck and I could settle down to the longer-than-I-expected task of wiring this new panel in.
The first step was to hunt around for the wiring diagram I had prepared - I tried finding some software to do a neat job of this, but I didn't fancy paying for a package that would only be used once, and all the downloadable ones seemed to prevent you from saving the diagram you had painstakingly drawn:
The camper was then transformed into a little workshop:
The first real hands-on step was to remove the battery and do something about the lack of fuses - having un-fused high-amperage cable snaking around the camper didn't make me feel comfortable:
The removed battery revealed the battery bay - you can see the drain valve that the pieces of wood kept the battery from fouling:
I took one of the two pieces of wood and sawed it into 4 with the circular saw, then located yet another spare piece of roof marine-ply and cut it to make a little platform to clear the valve. I screwed the wood to the floor from underneath the camper, then screwed the plywood to the 4 pieces of wood from above:
To tackle the lack of vent pipe I found an old piece of plastic piping and part of a high pressure air fitting that just fitted into the vent hole in the battery. I jubilee clipped the two together:
The battery could then be fitted in place and held there using an old mini-ratchet-strap handle with an off-cut of webbing taken around the battery and both ends fed into the ratchet strap spool - seems to work well (and again cost nothing):
Now the evil converter could be removed. Stupidly I failed to make a note of the wire colors, and only later did I realise I couldn't 100% guarantee that green was +ve. Though looking at this picture later showed green was indeed connected to the blue +12v output from the converter:
When built Shadow Cruiser had labelled many of the wires - with Biro on masking tape - not a particularly long-lived, but luckily most were still in place, so I was able to re-label them in indelible ink on plastic table-ties - the type with little tags on the end for writing on.
So with all the wires labelled I could get out the wire cutters - no turning back now :E
I had carefully measured the cut-out the converter was in and used that to specify the dimensions I had available in the new panel to fit components into. Of course, to measure this last August I just slipped the converter out an inch and measured the top and side of the hole. What I didn't see because I hadn't remove the pane entirely was the the front edge of the hole was angled. So when I offered the new panel up it wouldn't fit in :S
The quickest solution was to take the hole-saw and use it in a way its instructions probably explicitly forbid for safety reasons - that is using it like a sort of aggressively serrated angle-grinder to trim the offending timber, hoping not to trim any important electrics or indeed body parts in the process:
I decided that first off I needed to tackle the 240v AC wires. These are solid copper cores so have to be twisted into place. Plus I wanted to be able to wire them into place out of the way to achieve a degree of separation from the 12v electrics. The area under the wardrobe (behind where the converter used to be) was now a mass of jumbled wires, so I suspended the 12v wires from the coat hangers at the top of the wardrobe to give me room to work:
First I screwed the DC-to-DC converter into place. Then screwed a terminal block into place behind it for the 240v and fitted the wires between that and the control panel - with the 12v wires hanging out of the way it looks quite neat:
With the 240v wired I could cross my fingers and switch it on, check that the indicator light illuminated, and that the power sockets and fridge were then live - yep, all working. I then unplugged the hook-up again to avoid any nasty accidents while working in that area.
Next was the high-amperage part of the circuit. Again, these are awkward because they are thick cables (16mm sq). This involved the cables from the battery to the isolator, solar through another in-line fuse to its isolator, isolators to D250S and another distribution block (this one dedicated to 12v) and charging output from the D250S to the distribution block.
Next I completed the wiring of the control panel - wiring in all the smaller 12v wires - this was quite a lot of work:
This left a pair of wires I couldn't identify. I recalled they were connected to another wire from the truck that I had previously labelled as "not connected". I tried to trace the wires - the went to the back of the camper, but to no avail. I therefore terminated them and coiled them neatly out of the way. Then I found another matching pair of wires, this time coming from the front of the camper. Again they had the same shade of green (different from the green of all the other internal wires). It suddenly occurred to me what these green wires heading for the top front and top rear of the camper were - clearance lights! Of course when I tested the wire it was dead - it would only have been live when the truck lights were on. So I had to re-wire these.
The new panel could then be screwed in place and the wires tied together using cable ties into neat-ish bundles, designed to allow the panel to be removed or other components to be moved:
The last thing I wired in was the -ve 12v wires. I cable-tied them all together so I could then trim them to the correct length, and then wired them into the 12v terminal block.
I then carefully tested all the electrics - hooray - everything worked first time - no bangs, no flashes, no nasty burning insulation smells:
I'm pleased with the outcome - it was a lot more work than I expected, but I am really glad the camper is usable again. I hate having things in pieces so I can't use them.
Steve.
