Organising the 24Vdc had me a little concerned to begin with. The plug and cable supplied with the fridge is marked as 12/24v but there is a big sticker on it saying "12V only"!
This is because here is a little green diode on it which lights up when there is power connected and inside it is a special fuse which does not work properly with 24v!
Now IMHO they should also supply an alternative fuse for 24v connection - but that would still not prevent the diode from burning out. It really is only the size of a little resistor inside there somewhere which needs to be different from one voltage to another. Surely a little switch and extra resistor could be incorporated for about 5c!
An additional concern is the socket into which the plug goes. These plugs are intended for auxiliary power sockets in cars etc. - the problem with these is that they are not designed for anything other than a hole in a piece of sheet metal! The style of plug and socket for DC components in other installations is quite different and would mean cutting the plug off the cable
and using something else - which of course means you can't then use it in a car again without getting another cable "just in case" - about $50 !!
So I decided to pay a visit to the local "12V Shop" specialists to see if anything else was available.
We can live in hope can't we???
Lo and behold - secrets are revealed !!!
It appears that the plug is actually two plugs . . . one screwed into the back of the other.
And not only that but there is a nice wall mount fitting into which the hidden plug can now be screwed to ensure it doesn't fall out with vibration. And if you want to use it in the car again you just need to screw the original top back on. Things just keep getting better and better . . . there has to be a catch somewhere . . .
And of course there is . . .
In all this low voltage DC wiring you need to use very heavy wiring to prevent resistance, heat, voltage drop etc. etc. etc....
So of course on the back of the socket are the two smallest - stupidist - useless connectors imaginable. How the hell are you supposed to make a decent connection to them??
It would appear "only with the greatest of difficulty" . . . fortunately the material for the socket is fairly heat resistant so about 30 minutes of contortion in the cupboard with a soldering iron finally sees the installation done. You will also notice the addition of a 240Vac socket "just in case something goes wrong".
I still needed to make sure the fridge did not fall off the sliding platform on which it will be mounted.
First step is to attach the "cups" for the feet. At the same time a "riv-nut" was inserted into the frame
and a hook screwed into it.
Some brackets were attached to the fridge where the handles would normally go and turnbuckles fitted into them.
The fridge is then loaded on and the turnbuckles tightened into place
I don't think that's going too far !!
While down in the corner it seemed a good idea to put a couple of labels on the 24Vdc panel.
Thank you Mr Dymo.
A bench top 240Vac socket (GPO) is handy for several cooking appliances, but apparently they must be a minimum distance from the sink ( I don't know what that distance is ) but right up in the corner is about as far away as I can get and still be useful so that's where it's going!
Of course all outlets in motorhomes etc. must be "double pole" (which means that both active and neutral wires are switched - normal switches only operate on the active wire) read "costs twice as much"!
So re-route the cable previously tucked out of the way and screw it all into the selected spot.
One of the things left to test is the generator input so an appropriate cable and junction box needs to be installed so he generator can be plugged in.
This has been an interesting point of contention with the system suppliers and myself. The system has the capability to make use of and provide quite substantial amounts of power which has meant some pretty heavy duty wiring here and there. Similarly the generator has the ability to produce substantial power - about 23amps max.. Normal extension cables and power outlets are rated at 10 amps so the generator has three outlets on the front panel (which are rated to the next size up at 15amps each). All this means that if you turn everything on and have flat batteries the system can deal with it all quickly. Provided that the cables etc can carry the power. So the suppliers want to cater for the maximum disaster possible and install cables and plugs etc capable of 20amps plus. My argument is that if you ever get in that position - something has gone wrong!! So much to their disgust I have said to put in a single 15amp connection from the generator and program the system not to draw more than that. If it doesn't work out it will only need the connections upgraded and reprogramming - I can live with that.
Similarly the system can detect whenever the batteries get low and or I am using considerable power and can start the generator automatically. This is fine for a fixed installation, like a remote farm house, but I am not sure it's appropriate for a 4WD truck lurching along a bush track. For a start you would need to leave the ignition and fuel switched on while travelling. This is not a good idea . . . normally you turn everything off while travelling . . . imagine a water pipe breaking and the pump sees that as a tap turned on and proceeds to empty your water tank onto the floor.
So again in spite of "not realising the full potential of the system" I have diverted the automatic start signal to just light up a diode to say "start the generator".
So cable, diode, resistor and heat shrink
assembled ready for installation.
The best place to put it seemed to be in the control panel mounting box so the next job was to get that installed. So mount the box on the wall just above the switch panel.
Drill a hole and pull the cables through
And fit the front panel and the diode in the top left corner
Now I think I have to go outside and do some stuff there and the temperature hasn't gone down any that I can feel . . . .
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