General Bus electrics-Solar

[Kappy]

I'm quite new in RV game and quite a novice in when it come to Solar electrics etc.

Recently I embarked on making some cosmetic changes to my Bus and trailer and like always things seem to expand.

Having a few power issue and just scratching the surface in learning about electrics and my future needs on the road, plan to embark around January 2017.

Discovered some the than average issue with the fit out of my rig.

The other day inspected the junction box on my roof for the panel only to discover consideration water and corrosion on the terminals.

Appears my panels are set up so all the positive from the 3 panel are connected same with the negatives.

Researched pros and cons of parallel and series and now totally confused as to what is better.

So from what I heard started me looking at my batteries , I have 4 12V 100ah AGM, me thinks I have 400 ah, but I have 24V system so maybe the batteries are connected so I have 24 V and 200ah . once again series or parallel.

If batteries connected to get 400ah then I would have 48V Yes?

So nect week must source some 4 gauge cable connectors and some new terminals.

Cheers
Kappy

[BruceS]

I think you really need to get an expert, or at least someone who has done some installs, to take a good look at your complete electric setup Kappy.
It's probably correct connecting the pos & neg if you're running 12v or 24v if you have 12 or 24v (nom) panels.
We don't know which you have?
MC4 connectors are water proof and don't need a junction box. (that fills with water!)
http://www.ebay.com.au/itm/1Pairs-x-MC4 ... Swu1VW4lkV
Consider using proper solar panel cable too........... double insulated and a good fit in the connectors.

[SteveW]

Agree. Would hate to see a fire start as a result of varying size cables in the mix - it can happen easily with 12v spaghetti.

[bagmaker]

Hi Kappy
if the house batteries are connected in series you would have 100Ah @48v
in parellel you would have 400Ah @ 12v
or a mix of series and parellel will get you 200Ah @24v.
Its most likely your bus system (the cranking and running of the bus, not the RV house) is 24v. What usually happens is we get a hash up of 12v, 24v and 240v but its best to stay away from the 12v if you can, minimising wire sizes.
Few of us do

[Kappy]

Thanks guys,

Yes the bus/vehicle electrics is 24V with the exception around the cab area where a 12V converter has been fitted for stereo etc.

The house system is definitely 24V ,multimeter says so, voltage coming out of batteries is 24V (around 27 actually)

The panel wiring, is positives all go one terminal and all the negative go to another terminal then down inside the bus.

Panels are http://www.solardesigntool.com/componen ... sheet.html

Seems as if the house batteries are in mix of series and parellel @ 200Ah 24V

Still getting my head around this series and parallel and whats the better way to go, one site I went to stated the end result is the same which is confusing.

[JohnM]

When I first set up my bus I set it up as 24v house and motor, however many of the electric fittings I used were 12v (radio, TV, range hood, Toilet, hot water system ignition etc) I originally set up using a 30a 24v to 12v converter, (Dick Smith branded) however after having problems with flat batteries, I started off with insufficient Solar as well, I found out that the converter was using 0.8 amps at idle which didn't take long to flatten the batteries.
I quickly changed the house back to 12v converted the lights back to 12v LEDs used the 12 / 24 converter under the dash to run the radio, GPS etc Run of the ignition switch, so was left with 12v house and 24v motor run as two fully independent systems, even went so far as connecting 2 50w panels and a 24v regulator to manage the Motor batteries when the bus is sitting and the alternator while driving, the house batteries are charged via a Dc/Dc Redarc12/20 battery charger which will handle up to 30v input. as well as that I have both 12v and 24v battery chargers that can be run off shore power and the 24v one can be run off the house batteries, via the inverter, if I have flat motor batteries which has happened on the odd case when the door switch is left in the open position, accidentally, I have eliminated this now by placing an amber clearance light on the dash wired in parallel with the door switch. Shows up like the proverbial dog's appendages, when the switch is left on.

[SteveW]

It would be surprising to find the house on 24v.

[Wilbor]

It would be surprising to find the house on 24v.

Wilbors house is 24v. (Wilbor 1 that is)

[SteveW]

That's a surprise, then.

[dapope]

Our old winniebago had 24v house...