Any recommendations re what setup you would use for my requirements below? Basically I'm building (slowly) a small DIY caravan and just getting into the power/solar/appliances aspects now. I'm not so much after the specific sizing of say batteries/panels etc, but more so the setup concept such as: - need an inverter or not - charging approach (charge caravan battery when driving?, or only need to charge with solar panel or when plugged into 240V mains?) - given what I'm doing is there some battery management type system that does multiple roles? - maybe what I need is given my devices (listed below), and the fact I will have (a) 240V plug into caravan, (b) solar panel and (c) towing car can provide 12V, then what device(s) do I need to integrate everything together?
Requirements:
(a) No Access to Power (e.g. camping)
* Will have Gas fitted for a cooktop (certified) * Fridge - 3-way, something like "Dometic RM2350-RB Fridge - 90 Litre - Gas / 12v / 240v. 521w x 756h" [seems that it's not too much more to get 3-way?, and given I'll have gas fitted already] * Little water pump (potentially) for sink * Lights (LEDs no doubt) * Charging outputs for iPhone/iPad etc * Charging for Laptop/MacBook (??? does this imply I need a small inverter I guess???)
(b) When at caravan park with 240V * Microwave (doesn't have to work when camping away from 240V outlet) * 240V outlets for when caravan connected to 240V mains
Notes: * Not really sure if need 240V available when off camping (no mains available), however the charging of PCs/Laptops probably means I do, however I'm thinking it would not have to be very big (i.e. assuming I'm not going to try to use it for a microwave for example)
-- Edited by mixedup on Tuesday 26th of July 2016 02:43:23 PM
We have 30 amp Morningstare reg 80 amp /3000 watt battery charger / inverter combo .with originally twin 120 watt solar with 2 X 100 AH batteries .. I have added more solar panels which helps big time on overcast days . Me reg goes into trickle charge between 10 and miday .. Where as with out the added panels .. Some days the batteries don't get fully charged..
Mixed up, Free camping use your 3 way fridge on gas and not 12 Volts, the current draw of the fridge will kill your house battery real quick. Maybe have a look at a 12/240 Volt compressor fridge.
Battery size 2 X 100 Ahr deep cycle batteries. At least 200 Watts of solar to charge batteries while free camped. A 30 Amp regulator/ solar controller to look after the house batteries. Your caravan will most likely have some sort of power supply to run your equipment and charge your house batteries while plugged in to 240 Volt mains power.
As for the rest, 12 Volt lighting, Charging for I phone's etc. As for the lap top computer, there are on the market there are 12 Volt power supplies on the market that will step up the voltage to charge or run your lap top. It's far better to use one of these than use a inverter and the lap top's power supply. The current draw would be a lot less.
Radio's, television's, and a lot of other things can now be run off 12 Volts.
Re "Maybe have a look at a 12/240 Volt compressor fridge" - do you mean this might be better than a 3-way fridge?
Re "Your caravan will most likely have some sort of power supply to run your equipment and charge your house batteries.." - no actually, well not yet, as I'm building it myself. One way to ask my question about what devices I need to integrate everything might be by asking the following:
Q - Can I connect all of the following up to my "2 X 100 Ahr deep cycle batteries", or do I need some system/devices to assist here: (i) 240V battery charger DC output to connect to battery to charge it (ii) Solar panel output (I'm assuming the solar panel comes with a specific solar regulator, so I really mean the regulator output) (iii) 12V output from Car Battery/Alternator (iv) Connection to 3-way fridge (although if I've got gas, I guess this would be just a backup in case the gas runs out?) (v) Other 12V appliances lights etc
Can I literally connect all this to the batteries, or is there some battery management system or device you need to manage this?
We have 2x100amp batteries and a large inverter to run the coffee machine & frothier in the morning. We only use the fridge on gas when free camping. The 200w solar panel on the van and the 120w folding panel keeps the battery charged, but I imagine they would struggle if there were weeks of rain or heavy cloud. Yes, on big trips we do take a generator just in case of the bad weather!
We run the fridge on 12v from the car when travelling and not the van batteries! Purchase a fridge which has auto select for its power - ie 240v or gas or 12v (in that sequence).
Occassionaly the inverter is used to run the microwave for short periods.
BTW - ensure you install LED lights - they certainly reduce your power consumption.
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Glen
A diesel Nissan Pathfinder towing a Coromal Element 542.
Hi Treecrest14 - do you just hook up these various devices directly to your van batteries (i.e. the items that charge the batteries and the items that use the batteries)?
(thanks for the pointer re a fridge with auto-selection)
Usually a heavy wire to fuse box inside ? Main or big draw current like inverter or fridge canbe direct to battery . Yes just run 3way on DC when driving . With relay which turns on when engine is running . Inverter is mainly for short runs like microwave , coffee machine . Gas will do cooking and water heating depending on battery storage .. Our TV's etc are 12v now . Even lights are LED .. A good charger with generator can boost battery charge with two or three 10 - 20 minute runs through the day ? Often we use this to boil the jug ? Depending where we are and battery / cloud condition .. We never run gene at night though !!
The inverter is direct to the batteries, while all the 12v items are to installed outlets via permanently wired fused outlets as I have the batteries under the bed. The inverter is also under the bed as the shorter wire run to it the better. Then I have a 240v power lead from the inverter down beside the bed with a remote inverter on/off switch.
Battery charger is 240v and is permanently wired to the battery and so too the solar controller - both units being not under the bed.
You can purchase a good DC voltage drop relay on ebay which will disconnect the power to the van fridge when the car battery drops less then 12.?v - ie the vehicle is off and the fridge is connected to the vehicle.
Trust this assists.
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Glen
A diesel Nissan Pathfinder towing a Coromal Element 542.
Mixedup,
There is a very good site to look up for your 12volt and 240 power questions on "Collyn's page"
check this out on google, very good in my opinion also look up the name "Collyn Rivers"
Pomme.
