Skip to main content ↑ ↓
Topic: 12 volt only in my coach, (Read 879 times) previous topic - next topic

12 volt only in my coach,

Away for the weekend,  I have noticed that my coach only runs on shore power or generator,
It is not set up for totally off grid with out a generator attached to it,
I have removed the generator, It was cactus, The electric side of it,  and the gas bottle would not be approved here,
I have gone 4 x 8 Lb bottles of BBQ gas for stove and fridge, ,
So I have to redesign the power system in my coach,
I have plenty of power with 675 Amphrs of AGM batterys, 600 amhr plus a 75 amp start battery, 900 CCA,
700 Watts of solar on the roof, 40 amp solar controller,
I need to put a circuit breaker in from the house batterys to the start battery so I can charge it when its just sitting there unused,
A new 240 volt x 3000 Watt invertor to run the 110 volt systems I have still in the Coach,
Which I will run off a transformer from the invertor, 240 volt to 110 volt,
That will allow me to plug in 240 volt bits that I might use, Laptop, Etc,
I am totally a free camper,  So I have to be totally off grid in my power useage,

Im not sure about the OEM charger that charges the house bank from the shore power,
But I think I will pull that out as I no longer will have shore power,
And I dont think its connected any way,
Currently, I have 240 volt power in from the shore power into a transformer to the switch board,
But the 110 volt wires are just sitting there under the bed unconnected, ??????????

Re: 12 volt only in my coach,

Reply #1 –
Kinda complicates things having to work with two different voltages...

I'm sure our electrical gurus will come with a number of suggestions to separate you from your money.  They've helped me do that many times.

The OEM charger that charges the batteries from shore power is probably not worth saving.  An upgrade there would be kind to your batteries.

Normally on our (stateside) coaches, the combination inverter/charger is used to charge the house batteries when on shore power.  You just need a 240 volt inverter/charger plus a manual switch to connect the house batteries to the start battery.

What purpose would the 110 wiring serve, assuming you got it hooked back up?  Could you use the old 110V wiring to circulate 240 volt power by just changing the duplex outlets to Aussie style?

Lots of questions...

Re: 12 volt only in my coach,

Reply #2 –
Yes, get a smart charger that operates on your 240 VAC.

And several options for keeping both battery banks charged.

Both solar and your new smart charger should be connected to the house battery bank.

Options to charge the chassis batteries are several.  As a boater, the simplest is a marine ON-OFF switch with cable to chassis battery on one side and cable to house battery on the other.  ON, chassis batteries are charged from the house.  OFF, they are separated.

Re: 12 volt only in my coach,

Reply #3 –
Quote from: Chuck & Jeannie –
Kinda complicates things having to work with two different voltages...

I'm sure our electrical gurus will come with a number of suggestions to separate you from your money.  They've helped me do that many times.

The OEM charger that charges the batteries from shore power is probably not worth saving.  An upgrade there would be kind to your batteries.

Normally on our (stateside) coaches, the combination inverter/charger is used to charge the house batteries when on shore power.  You just need a 240 volt inverter/charger plus a manual switch to connect the house batteries to the start battery.

What purpose would the 110 wiring serve, assuming you got it hooked back up?  Could you use the old 110V wiring to circulate 240 volt power by just changing the duplex outlets to Aussie style?

Lots of questions...



The 110 wiring still has the microwave and food processor in the bench that I would like to use,
The food processor and all its various bits was the only thing not stolen on the way over here,
The vaccuum cleaner, The garbage squasher, I dont need, Its now just a rubbish bin,  the ice maker has been removed,
A transformer will run these two from a new 3000 watt invertor,

As part of the conversion in California, They ran 240 volt wiring thru the coach, Replacing the 110 wiring, This 240 volt wiring is all new wiring,
Its seperate from the 110 volt wiring, And it has 240 volt GPO's,

The OEM charger I will remove, It serves no purpose to keep it,

Re: 12 volt only in my coach,

Reply #4 –
The same wire is used for 110 and for 240 volts. The size of the wire dictates how many
amps can run through it.

Re: 12 volt only in my coach,

Reply #5 –
Quote from: wolfe10 –
Yes, get a smart charger that operates on your 240 VAC.

And several options for keeping both battery banks charged.

Both solar and your new smart charger should be connected to the house battery bank.

Options to charge the chassis batteries are several.  As a boater, the simplest is a marine ON-OFF switch with cable to chassis battery on one side and cable to house battery on the other.  ON, chassis batteries are charged from the house.  OFF, they are separated.

I have a smart charger that plugs into the 240 mains or a generator, If I need it,
But the solar panels are more than enough to keep the batterys charged,
Plus the diesel charges the start battery as Im driving along,
Im not sure if the diesel alternator charges the house batterys or not, But they are fully charged off the solar panels any way, So not an issue, 

The solar panels are permanently connected to the house batterys thru a 40 amp solar controller,
It has all sorts of inbuilt protection,  Under power, Over power, back flow at night, Cant over charge the batterys, Etc Etc,  Its the same system I have on my boat, and it all works perfectly,

The on off switch, I have a circuit breaker that I will use instead to connect the house batterys to the start battery, Just to keep it charged when the coach is not in use,

I used the start battery, 75 amhr AGM on my boat just in case the batterys got flat after about four days with out sun, It just sat in the cockpit, unconnected, Jumper leads I carried to give the house batterys a bit of extra charge if they got down,  to start the diesel to charge the batterys,
It held its charge very well over 12 months on the boat, , A yellow 900 CCA Optima, It starts the diesel in the coach instantly,

So basically, I just need a new 3000 watt invertor, and a new Transformer, And Im all set to be totally off grid, and fully self sufficient,

The Dometic fridge on my boat I ran on gas, As on 110 volts, It would flatten the batterys over night, It sucked power,
8 Lb bottle of gas lasts about 3 weeks using fridge and oven for cooking, I carry 3 spare bottles,
My Laptop sucks huge power also, 

Bottom Piccy, where we atayed last weekend before I ripped the filter off, Is 30 Klms from the top of Mt Buller where I go skiing in winter, Its just before the gate house where they charge entrances fees,
Its a great spot right beside the river,


 

Re: 12 volt only in my coach,

Reply #6 –
REPLIES IN SOLID LETTER CAPS

Quote from: Mr B3 –

Im not sure if the diesel alternator charges the house batterys or not, YES, THE ALTERNATOR THROUGH THE BATTERY ISOLATOR SHOULD CHARGE BOTH BATTERY BANKS.

The on off switch, I have a circuit breaker that I will use instead to connect the house batterys to the start battery, Just to keep it charged when the coach is not in use,  SO IT IS A HIGH AMP CIRCUIT BREAKER THAT YOU CAN TURN ON/OFF?  NEEDS TO BE ABLE TO HANDLE FAIRLY HIGH LOADS IF ONE BANK IS DEEPLY DISCHARGED.
 

Re: 12 volt only in my coach,

Reply #7 –
Quote from: wolfe10 –
REPLIES IN SOLID LETTER CAPS


Yes, Brett,  it is a high amp circuit Breaker, 50 amps, Its very small in size, I can fit it any where, easily,
I just bought another two off Ebay,  $24-00 for two,
They are what I had on the boat for the solar panels and Wind Generator, I also have one on the desel motor as a main power switch,
They are a very solid and well built switch, Chinese of course, Hahaha
The marine, on off switches are very large, 4 inches or so in diametre, Too big for what I want,

Re: 12 volt only in my coach,

Reply #8 –
Should work just fine "with your supervision".  With your knowledge of 12 VDC you will not let one battery bank completely discharge and then connect it through that 50 amp breaker to a fully charged bank.  The in-rush current could well exceed 50 amps.

That would be a time for "Plan B"-- use jumper cables or other connections that could accommodate the in-rush current until "transfer" amps is less than 50.

Some owners require "fool-proofing".  Others know how to manage mechanical/electrical issues for themselves.  The same plan does not necessarily work for both!

Re: 12 volt only in my coach,

Reply #9 –
Quote from: wolfe10 –
Should work just fine "with your supervision".  With your knowledge of 12 VDC you will not let one battery bank completely discharge and then connect it through that 50 amp breaker to a fully charged bank.  The in-rush current could well exceed 50 amps.

That would be a time for "Plan B"-- use jumper cables or other connections that could accommodate the in-rush current until "transfer" amps is less than 50.

Some owners require "fool-proofing".  Others know how to manage mechanical/electrical issues for themselves.  The same plan does not necessarily work for both!

My solar Panels keep the house batterys at 13.4 Volts, Im happy with that,
12.4 volts is when I do some thing about low battery power, Either start the diesel to recharge, Or go looking for what is causing the low power in the batterys,
Also turn everything off,
No sun is knowing the batterys are getting down,
House bank to Start battery is only a trickle charge at the best of times, Its only to maintain a full start battery,
I need a full 12 volts to open the fuel solenoid on the motor to get the motor to start,
The new circuit breakers I bought are slightly different to the piccys I posted up above, They are still 50 amp but have a different configuration, The wires go on the front instead of behind, Easier to fit,

My new 500 watt Transformer, 240 to110 volts was $32-00, Delivered,
My new 12 volt to 240 volt pure sine invertor, 3500 watts with a 6000 watt surge and remote with 4 outlets, Will be around the $300-00 mark,  or just above,
Solar power in OZ is very cheap as it is in very high demand and very very competitive,

Re: 12 volt only in my coach,

Reply #10 –
And your gov't hasn't figured out how to tax you for the solar power--------YET!!!

Re: 12 volt only in my coach,

Reply #11 –
Quote from: nitehawk –
And your gov't hasn't figured out how to tax you for the solar power--------YET!!!
Yes they already do, You get almost nothing back for putting it back into the grid if your connected to it,
Electric cars, so much per Klm, hahahaha
 

Re: 12 volt only in my coach,

Reply #12 –
Thanks to the info I got on here and the knowledge I learnt setting up my boats 12 volt solar system,

I have finally figured out my Coachs weird wiring, Hahahaha
Not being a sparky, I had no idea on it all,
Firstly. I pulled the charger out of the Coach, Its redundant any way, Thanks, Brett,

I plugged it into the 240 volt mains power and turned every thing on, on the power boards,
Making sure nothing was getting hot or smoking, Hahahaha,

It comes into the coach, then thru a circuit breaker mains board, 240 volt, This is all new and not OEM,
Then it goes into the wiring for 240 volt thru the Coach,
It also goes into the new 240 volt transformer and then into the 110 volt system on board, All OEM,

Zip, Nada, Zilch. Nothing, Then I noticed a small switch under the bed, Just an off on switch,
What does that do, I flicked it on, I have power in the coach after checking the AC units, They work,
I went round and plugged my drill into all the outlets,  They all work,
The OEM micro wave will only run for a few seconds and trips out, No idea there, ????????
The food processor on the bench works, Thats great,

My new set up, system for 12 volt only,
I have decided to keep the 240 volt mains inlet just in case I ever need it,
It will be plug in only as needed,
700 Watts of Solar Panels direct to the 600 amphr AGM battery bank via a 40 amp Solar Controller, and a fifty amp circuit breaker,
Batterys are in Parrellal,
Solar panels are in Parrellal,
Then into a 12 volt to 240 volt,  Pure Sine wave,  3500 watt invertor, Then into the 240 volt wiring in the coach,
The 240 volt to 110 volt,  500 Watt Transformer will plug into the Invertor, Then into the OEM 110 Volt wiring into the switchboard under the bed,

What it has cost me to be totally 12 volt off grid,
3500 - 7000 Watt invertor,                        $287-00
2 x 350 Watt Solar panels,                          $270-00 Total,
50 Amp circuit Breakers,  x 2                      $25-00
500 Watt Transformer,                                $32-00
600 Amphr AGM batterys,  3 x 200,          $900-00  S/H,  Came out of a Computer Back up system,
Solar Controller, 40 Amp                            $60-00

Yep, its all Chinese, but sourced from local suppliers, All came off Ebay,

Still got a bit of work to do on it, But I am slowly getting there,
Most of it has been tried and tested on my Boat over the last 12 months of full time live aboard,

Bottom two piccys is the OEM Charger I pulled out of the coach,