Charging a Fullriver 120AH in my D2, a couple of Q's

[winaje]

Hi all. I'm after a bit of advice on setting up my dual battery system. I've spent several hours/days reading the existing threads, but have not found one that represents my setup. Using 6B&S from the main battery which is a Caterpillar 115-2422 1000CCA, to a Fullriver 120AH DC battery which I'm going to mount in the right rear storage bin. Fullriver has 24A ideal charge at 25c which will run a Waeco CF-80DZ, Waeco site says: "Av. power consumption: 2.9 Ah/hr (@ 12 volt, 5 °C fridge, -15 °C (approx.) freezer, 32 °C ambient temperature)".

1. Am I correct in assuming say 5 Ah/hr for safety, in case I run the fridge at -18c and the ambient temp is higher in the car? And am I right in believing that I should not take the battery below 50%, so at 5 Ah/hr I'd get about 12hrs before needing a recharge?

2. I have a Traxide SC-80, and have had confirmation from Tim that the alternator in my D2 TD5 will charge it without issue.

3. I'd like to be able to run a solar panel on the roof of approx 80w, through a Plasmatronics solar controller, thinking of a Dingo 20A, negative switched.

4. Need to be able to charge the battery from 240vAC, so am considering permanently installing a 25A smart charger and hooking up to power when needed. Any advice on which one to use, for around $200?

5. I want to run the fridge 24/7, will be using some thermal mass fillers like water bottles etc to take up the space I'm not using for food/drink. Normally drive 22km to/from work, and park in the sun during the day.

Do I have all my bases covered? Do I need to install 1 way diodes to stop charge from one device feeding back into another? Any advice greatly appreciated.

Please don't degenerate into the whole SC-80 vs DC-DC charger argument

[warren9981]

Hi Winaje, I am currently undergoing exactly the same in my D1. I have a SC-80 under the bonnet of the D1. I have a Fullriver 105AH battery (in the camper trailer) and a Fullriver 55AH (in the rear of the Rover) both powering an Evakool 45L fridge. Issues I have found are: D1 vehicle alternator only puts out 13.7Vdc. I have been informed that the AGM batteries need 14.7Vdc to charge to maximum capacity.
My solution (just purchased today) is CTEK MXS15 battery charger to charge both batteries from 240Vac when at home or when 240Vac power is available, i.e. generator, campground etc.
Future plan is to install a CTEK D250S Dual in the Disco to fully charge both batteries when the vehicle is running and to provide capability to connect a solar panel to the same charger. No solar regulator is required with this charger.

On the issue of diodes I do not believe they will be required as the SC-80 isolates the start battery from the Aux. battery. The solar regulator you get and the 240Vac battery charger you get should have inbuilt protection to prevent back feeding. I would, however, install circuit breakers on each of the feeds to the battery so that if you have a short in any of the feeds you have some protection. (This is only my opinion though).

[drivesafe]

Hi Warren and could I ask who told you you need 14.7v to fully charge an AGM.

Who ever it was, they were either trying to sell you something you don’t need and/or they haven’t got a clew what they are talking about.

An AGM battery can be fully charged from as little as 13.0v. It would take around 30 hours to fully charge a low AGM, but you can do it.

The higher the charging voltage simply means the faster the battery will be charged to around 90-95%, but the final full charge state, for any battery, can take quite a few hours more and even when using a battery charger, the final state to get a battery to a fully charged state occurs during the float mode, when the battery charger is usually running at a lower voltage than your alternator.

The most important factor for both of you is the actual driving time.

Warren, you haven’t stated how much driving you will be doing.

Hi winaje and in your case, you are doing WAY TOO LITTLE driving to be able to do what you want with the fridge.

You would need at least a couple of hours driving time every day and that’s obviously not going to be the case.

You will need to drastically supplement the charging of your batteries with a battery charger, or make a big increase in your solar array..

To the size of the charger. If you have the time to charge the batteries, say over night, EVERY NIGHT, use a small charger, say 10 to 15 amps at most, even if you are running your fridge at the same time.

A long low current charge is way better for any lead acid battery than a short duration high current charge is.

[justinc]

thanks tim, just been through this with a defender customer today, i advised as per your advice to me ages ago, , he needs to supplement charge each night for a week to bring his pair of blue top optimas up to full, as he only drove about 5 to 10 minutes at a time after sitting for an extended time and both were very low.

worked for me, now i am sharing the lurve....

ps hope you are well and ready for another year at the coal face...


jc

[warren9981]

Drivesafe. Thanks for your information

A local battery place told me this. Also some battery sales sites have been indicating this.

My driving time is usually about an hour maximum from home.
On the odd occasion I could be travelling up to 7 hours a day if doing a long trip , usually in 2-3 hour stretches.

My requirement is as follows:
Camper trailer is parked in the garage for approx. 3-4 weeks. it is then taken out for a weekend and battery is used to run the fridge and LED lights. After the weekend the camper is put back in the garage until next trip. Battery charger 240Vac should be sufficient for this use.
From your provided information when I undertake long trips the vehicle alternator may be sufficient to charge the batteries whilst travelling. I may need to use solar if staying in 1 location for more than a few days.

I figure 105AH and 55AH should power the fridge for around 4 days (depending on other factors).

[drivesafe]

Hi again Warren and in your set up you did mention a generator. If you plan to do a lot of charging using the generator then you need a high current charger to reduce the amount of time you have to run the gen. You have no choice but to sacrifice battery longevity for charging time available.

If you are not planning on using a generator that much, then an even smaller battery charger would be better for your use.

Your driving times are a lot better and you should have no problems keeping your batteries charged.

[winaje]

Thanks to all for their replies.

Hi winaje and in your case, you are doing WAY TOO LITTLE driving to be able to do what you want with the fridge.

You would need at least a couple of hours driving time every day and that’s obviously not going to be the case.

You will need to drastically supplement the charging of your batteries with a battery charger, or make a big increase in your solar array..

To the size of the charger. If you have the time to charge the batteries, say over night, EVERY NIGHT, use a small charger, say 10 to 15 amps at most, even if you are running your fridge at the same time.

A long low current charge is way better for any lead acid battery than a short duration high current charge is.

Thanks Tim, it seems that I either need to increase my supply or decrease my demand. At this stage I'll decrease demand, and only use the fridge when I need to.

Is there any issue with the Fullriver being charged in 45 minute drives twice a day, for "the foreseeable future", but only having a load put on it every so often with the fridge?

[drivesafe]

Is there any issue with the Fullriver being charged in 45 minute drives twice a day, for "the foreseeable future", but only having a load put on it every so often with the fridge?

No mate, that should be fine, depending on how much power you draw from it when you do use it, but a 45 minute drive will keep it in a good state of charge.

[winaje]

Hi all. I'm after a bit of advice on setting up my dual battery system. I've spent several hours/days reading the existing threads, but have not found one that represents my setup. Using 6B&S from the main battery which is a Caterpillar 115-2422 1000CCA, to a Fullriver 120AH DC battery which I'm going to mount in the right rear storage bin. Fullriver has 24A ideal charge at 25c which will run a Waeco CF-80DZ, Waeco site says: "Av. power consumption: 2.9 Ah/hr (@ 12 volt, 5 °C fridge, -15 °C (approx.) freezer, 32 °C ambient temperature)".

1. Am I correct in assuming say 5 Ah/hr for safety, in case I run the fridge at -18c and the ambient temp is higher in the car? And am I right in believing that I should not take the battery below 50%, so at 5 Ah/hr I'd get about 12hrs before needing a recharge?

2. I have a Traxide SC-80, and have had confirmation from Tim that the alternator in my D2 TD5 will charge it without issue.

3. I'd like to be able to run a solar panel on the roof of approx 80w, through a Plasmatronics solar controller, thinking of a Dingo 20A, negative switched.

4. Need to be able to charge the battery from 240vAC, so am considering permanently installing a 25A smart charger and hooking up to power when needed. Any advice on which one to use, for around $200?

5. I want to run the fridge 24/7, will be using some thermal mass fillers like water bottles etc to take up the space I'm not using for food/drink. Normally drive 22km to/from work, and park in the sun during the day.

I have looked into semi flexible solar panels, and measured the roof. I can fit 330W on the roof, 3x110W connected in parallel to maintain 12V.

By my reckoning this provides 12V at 28A. Is this correct?

Considering one of these: POWERTECH 12V/24V 30A MPPT Solar Charge Controller | eBay

Am I OK to keep the solar charge and the alternator charge separate?

Will 330W charge the Fullriver enough to run the fridge full time, assuming that I get about 6-8 hours of sun a day?

Thanks