Triple battery setup run down.

[Cuppa]

O.k so I keep my SBI12 and buy a dc to dc charger and mount this in the trailer or in the rear of the car? Any recommendations on what charger?

What capacity trailer battery?
What is the average daily power usage (amp hours) of your fridge, plus any other power usage (lighting, music, water pump etc)
How often do you intend to drive?
Is this for weekends away, a couple of weeks away or longer?

The two name brands are Ctek & Redarc.
I have no experience of the Ctek, but others who have them are happy with their purchase.
I have a Redarc & am happy with my purchase.

Here is the Redarc range (ignore the prices, they can be bought a lot cheaper). The size which would suit you best depends upon the answers to the questions above.

A larger amperage unit will bring the charge of a depleted battery up to around 70% more quickly (less driving time) than a smaller amperage unit, but to get that all important top 30% into the battery will take the same amount of time regardless of the amperage of the charger, so choice is dependent upon how much you expect to take out of your trailer battery between (percentage of battery capacity) driving with the trailer attached.

eg. if driving (with trailer attached) all day most days it is likely that a smaller unit would do just as well as a larger one, but if stopping for a couple of nights at a time & taking more out of your battery, & then only driving (with trailer attached) for half a day a larger unit may be better.

In my case my batteries being charged by the Redarc 40 amp charger are 3 x 120Ah, possibly being taken down to 50% capacity over several days. In my case it makes sense to have a larger unit because the batteries would be able to accept the full 40 amps for 3 hours plus in such circumstances, & a reduced charge until full for the rest of the driving day. Most of the time my batteries would not be taken down to 50% (using solar) & the full capacity of the charger not used, but the set up takes into account worst case scenarios, much more important if full time on the road.

Cuppa

[Winnie]

I have the standard setup in my car. Cranking and Auxilary battery. Our Camper that we have bought will have its own battery aswell. Which will run my 75L combi and a couple of strip lights. I ran my combi for fours days plus two lights on my current 110AH AGM I have, no solar charging too. Was quite impressed really.

Hugely depends on the weather, I've only got a cranking battery in mine and in winter my 40L fridge can run for a week and I can still start the car, but in warmer season it will be flat after 3 days.

[threedogs]

Some nights like last time we went away we didn't need camp lighting , only stars and campfire.
In the desert you can nearly read a book when the moon is full,
Some say during winter to turn your fridge off and leave lid open.
Never tried it but makes a little bit of sense

[mudski]

What capacity trailer battery?
What is the average daily power usage (amp hours) of your fridge, plus any other power usage (lighting, music, water pump etc)
How often do you intend to drive?
Is this for weekends away, a couple of weeks away or longer?

The two name brands are Ctek & Redarc.
I have no experience of the Ctek, but others who have them are happy with their purchase.
I have a Redarc & am happy with my purchase.

Here is the Redarc range (ignore the prices, they can be bought a lot cheaper). The size which would suit you best depends upon the answers to the questions above.

A larger amperage unit will bring the charge of a depleted battery up to around 70% more quickly (less driving time) than a smaller amperage unit, but to get that all important top 30% into the battery will take the same amount of time regardless of the amperage of the charger, so choice is dependent upon how much you expect to take out of your trailer battery between (percentage of battery capacity) driving with the trailer attached.

eg. if driving (with trailer attached) all day most days it is likely that a smaller unit would do just as well as a larger one, but if stopping for a couple of nights at a time & taking more out of your battery, & then only driving (with trailer attached) for half a day a larger unit may be better.

In my case my batteries being charged by the Redarc 40 amp charger are 3 x 120Ah, possibly being taken down to 50% capacity over several days. In my case it makes sense to have a larger unit because the batteries would be able to accept the full 40 amps for 3 hours plus in such circumstances, & a reduced charge until full for the rest of the driving day. Most of the time my batteries would not be taken down to 50% (using solar) & the full capacity of the charger not used, but the set up takes into account worst case scenarios, much more important if full time on the road.

Cuppa

Hmm O.k Trailer battery is said to be a 100AH.
Uses will be a fridge 75L Combi, specs say it draws 4.2amps maximum. Also running a small water pump for the kitchen tap and a couple of led strip lights (Which we don't leave on at night, only turn them on when we need to)
Music via my car...
Usage would be weekends and longer stays...
I do have the portable solar setup too but like I said I am considering selling it as its bloody massive, 3 panels hinged together, and heavy and getting something smaller and easier to carry. Either that or I will separate the panels so I can move them around individually. dunno yet...

Hugely depends on the weather, I've only got a cranking battery in mine and in winter my 40L fridge can run for a week and I can still start the car, but in warmer season it will be flat after 3 days.

My cranking battery is just that, a cranking battery. Apart from the radio everything else runs of my second aux battery.
Its funny how say ten years back I had everything running off a 9KG gas bottle. Now I only use a 2.5kg bottle and that lasts me all year... How times have changed.

[mudski]

I just got off the phone with the guys at Redarc. As I had my eye on the BDCD1220. He asked if I had solar panels. I do, so he advised I go for the BCDC1225 which is 25A and has a built in MPPT solar regulator. So the hunting begins....

[Cuppa]

I just got off the phone with the guys at Redarc. As I had my eye on the BDCD1220. He asked if I had solar panels. I do, so he advised I go for the BCDC1225 which is 25A and has a built in MPPT solar regulator. So the hunting begins....

Here ya go.
http://www.ebay.com.au/itm/REDARC-BC...fe02e03&_uhb=1

Seller is an authorised Redarc reseller. beware of others on ebay who are not. Redarc will only honour their warranty if the item is purchased from an authorised reseller. If an ebayer says 'return it to me if a warranty claim is required" forget it & look elsewhere. If purchased from an authorised reseller you deal directly with Redarc if there is any problem.

Cuppa
Ps. make sure you don't get a BCDC1225LV

[BigRAWesty]

I just got off the phone with the guys at Redarc. As I had my eye on the BDCD1220. He asked if I had solar panels. I do, so he advised I go for the BCDC1225 which is 25A and has a built in MPPT solar regulator. So the hunting begins....

Do your panels have a built in reg? If so there is no need for the 1225. Just connect your panels to the battery..
Father in-law has just gone threw the same thing now thinking about it..
He was looking at the c-tech equivalent of the 1225 A's he has an 80W pannel, but went the standard as the panel is regulated. He decided against cutting the reg Off as it is handy for the car when the trailer is not in tow.

[mudski]

Here ya go.
http://www.ebay.com.au/itm/REDARC-BCDC1225-DUAL-BATTERY-ISOLATOR-SYSTEM-DC-TO-DC-MPPT-SOLAR-4X4-4WD-AGM-/300914060803?pt=AU_Car_Parts_Accessories&hash=item 460fe02e03&_uhb=1

Seller is an authorised Redarc reseller. beware of others on ebay who are not. Redarc will only honour their warranty if the item is purchased from an authorised reseller. If an ebayer says 'return it to me if a warranty claim is required" forget it & look elsewhere. If purchased from an authorised reseller you deal directly with Redarc if there is any problem.

Cuppa
Ps. make sure you don't get a BCDC1225LV

I can get Redarc products direct from a wholesaler cheaper than any Ebay seller so I'm right there...

Do your panels have a built in reg? If so there is no need for the 1225. Just connect your panels to the battery..
Father in-law has just gone threw the same thing now thinking about it..
He was looking at the c-tech equivalent of the 1225 A's he has an 80W pannel, but went the standard as the panel is regulated. He decided against cutting the reg Off as it is handy for the car when the trailer is not in tow.

Yes my panels now have a Suntrans 20A regulator on the back of the panels....This is where I am stuck now. The trailer we are buying comes with a kit supplied and fitted which has the Anderson plug and lead running into a charger of some sort. It's a Repco branded charger, and I don't know of the specs but I think it wont be much chop. But the charger supplied also has a 240V connection on it which maybe be for charging from 240V???
My two options here...

1. Too remove the already installed Repco charger and buy a Redarc charger BCDC1225
2. Leave the Repco charger in, and move my Suntrans reg from the panel and mount it in the trailer and somehow connect it into or along side the Repco charger...I'm not sure how this will all work though...

[BigRAWesty]

First up, details on the repco charger.. You may not need to spend a cent..
But why remove the reg?? Why limit your panels to only charging the trailer. I'd leave reg on panels to allow solar charging of any battery me matter where it lays..

[mudski]

First up, details on the repco charger.. You may not need to spend a cent..
But why remove the reg?? Why limit your panels to only charging the trailer. I'd leave reg on panels to allow solar charging of any battery me matter where it lays..

Having the reg as far away from the battery isnt ideal. Plus having the reg under the panel it gets hot quicker and therefor will cut out earlier. So I have told anyway... as for specs on the Repco charger, I have failed to find anything on their website. I might have to just wait until I get the trailer, then worry about it. Not what I want but....