Redarc BCDC1240 Install

[farqman]

I'm looking for people who specifically have this unit as I have some questions.

I purchased the 1240 last week with plans to run it as a Dual Battery system in my 2013 Patrol.
I went to my local battery world and asked a few questions in regards to batteries and was quite suprised.

He tried swinging me towards a "ultimate" brand battery, once I Told him it was going in a patrol he said it wouldn't be covered under warranty due to heat issues with the GU i.e. Being too close to turbo.

He rang the guys at century battery to see if they would accept the 40amp charge from the Redarc and was told that they would (information online says only 20amp though??). Said I could get a Marine 730, but if it was to swell I would have to remove it, bring it in and claim it was installed in a boat as Century will not warrant a marine battery in a Car.

Basically I see my options as using a Optima D27, which is only 66ah, or spend big an get a Lifeline battery. Not sure if the lifeline will fit in the ARB tray though as the tray is on back order.

99% of the information I can find regarding the BCDC1240 is people using it in trailer setups or using multiple batteries.
Trying to work out if it's suitable to use on ONE battery under the hood, and what my battery options are.

Or, do I throw it in the cupboard and buy a standard SBi solenoid setup, and use the BCDC1240 in the cargo area with 2 batteries if I decide to go that way?

Desperately trying to get answers. Thanks

[the evil twin]

Devices like the BCDC1240 are designed to compensate for voltage drop over long cable runs so, no, you don't need one under the bonnet and an SBI is fine if you want to go that way.

The SBI won't do Solar like the BCDC will however the BCDC can't charge at 40 amps on Solar so if you go SBI then you need a Solar Reg but will get the same charging current out of the panel array.

Any battery under the bonnet needs to be able to tolerate high temps and a lot of deep cycles won't so you need to check manuf spec.

A lot of deep cycle batteries also cannot handle high charge current so again check the manuf spec

99% of the info is about trailers/caravans because that is what the DC DC chargers were designed for and the application that most people use.
Because the battery bank in Trailers/Vans/Motorhomes are often a long run from the charge source and large capacity of severalk hundred AH but situated in ambient temp (IE not next to an engine/turbo) so the issues you have 'under bonnet' aren't a factor.

[the evil twin]

... forgot to mention.

The BCDC should be as close as practical to the aux battery however under bonnet temps will cause the internal sensors to reduce the available charging current so I would take that into account.

Bottom line IMHO is this... unless you are running Ca batteries and/or Solar then you don't really get much advantage in an under bonnet install from DC DC chargers over VSR devices like the SBI

[Cuppa]

The bloke at your local BatteryWorld needs to go back to battery school. If a single battery can be charged by a, say, 80amp alternator, why on earth would he even think that a 40amp DC to DC charger might not suit. I would be wary of any other ‘advice’ he offered.

Whether you should use the BCDC1240 depends upon where you want to mount it & what sort of use you want to put it to. It will not bring your aux battery under the bonnet to 70 to 80% charged any quicker than the alternator alone (via an SBI12 or similar) but it will ensure that you get the battery to full charge which the alternator generally won’t. Mounting the BCDC under the bonnet where it gets very hot will see it derating it’s ouput & possibly shutting down at pre-set temperatures so probably isn’t a good idea. (The manual says “The unit will operate optimally below 55 deg.C with good airflow. At higher temperatures the unit will derate output current”). In the specifications it also gives a maximum ambient temperature of 80 degrees C.

It’s also a bit of a waste if you are not planning to use it’s solar capability too.
I have one & like it, but have it mounted (together with the aux batteries) in the rear canopy charging batteries via solar & when driving. Another reason folk like them in caravans, camper trailers etc is that they will boost voltage, compensating for voltage drop. If your late model Patrol has one of those new fangled low voltage alternators, it would be useful, but not under the bonnet.

General consensus is that all AGM batteries dislike under bonnet heat & I don’t reckon Lifeline would be any different. However I’ve never had an AGM under the bonnet but would suggest that no battery likes extreme temperatures. Wet battery fans claim they are better under the bonnet, but my experience is that when fully charged by a smart charger (dc to dc, solar reg or mains) they will gas & lose fluid, the excessive temperatures would only exacerbate this. Regular monitoring & topping up would be essential, something many folk fail to keep up. Result is short lived batteries.

As you have purchased the BCDC I would suggest using an AGM battery or batteries of your choice mounted inside the vehicle the BCDC close by. Another thing that using it allows for is charging of aux battery(ies) of a different chemistry to the crank battery.

All of what I’ve said is based upon the assumption that you want the aux battery or batteries to be deep cycle item(s). These cost more than crank batteries & can last for many years more if treated well. This is a primary reason for using a BCDC1240 & battery mounted inside the vehicle. If you decide to put the aux battery under the bonnet I’d suggest that you use a SBI12 or similar & use another crank type battery, with the expectation that you will need to replace the battery more often. Of course by doing this you will have less ‘useable capacity’ when you get to camp (although you could fully charge the aux battery with a mains smart charger before leaving home). This would be a useful strategy for weekends away, but less so for extended touring, hence my earlier comment about what you do should be determined by the intended use.

I am hoping that this thread might draw comments from folk who have used AGM’s under the bonnet, because to date there is this common perception that it’s not a good thing to do, but I can’t recall hearing of first hand reports.

[BigRAWesty]

A simple shield around the battery would aid in any heat issues your battery might see. But in all honesty plenty of blokes been running the exact same thing as you want to do for many a years.

I'd go back to that "battery bloke" and tell him to shove his bs advice.

As cuppa said the unit may not like the temps. So if your set up allows it may be best to mount a gell in the read with the redarc next to it.

[farqman]

Mounting the unit isn't a huge issue. A member on another forum mounted his between the radiator and grill. Being in this position would allow for plenty of air flow.

http://i272.photobucket.com/albums/jj200/benwilson1/aef13e11be392221aa576412f0c34950.jpg

I had planned on using the solar function later on down the track hence why I went for the DCDC charger. Might have to shelve it and go the solenoid path. Just pissed I spent so much. Was a special order so not sure the auto elec would offer a refund.

[Cuppa]

however the BCDC can't charge at 40 amps on Solar

Ummmm, yes it can


A lot of deep cycle batteries also cannot handle high charge current so again check the manuf spec

I don’t really understand this. I know that there are recommendations of charging amps, generally around 10% of the battery’s capacity in amp hours, but if the battery is being ‘well looked after’ it will generally be getting charged before it is ‘over discharged’ & consequently the battery will only accept a lower charge rate regardless of the capability of the charger. The BCDC won’t force 40 amps into a battery any more than straight alternator charging would.

[Cuppa]

So if your set up allows it may be best to mount a gell in the read with the redarc next to it.

Just so we are clear, a gel battery & an AGM battery are not the same thing. https://www.batterywholesale.com/agm_gel.html although folk frequently (& mistakenly) use the terms interchangeably.

[macca]

Ummmm, yes it can


[/COLOR]
I don’t really understand this. I know that there are recommendations of charging amps, generally around 10% of the battery’s capacity in amp hours, but if the battery is being ‘well looked after’ it will generally be getting charged before it is ‘over discharged’ & consequently the battery will only accept a lower charge rate regardless of the capability of the charger. The BCDC won’t force 40 amps into a battery any more than straight alternator charging would.

Was thinking the same. I have recently installed a bcdc1240 in the pod with 2 new agm batteries. It came with a separate change over relay for solar input. If I had enough panels the amps would be the maximum the bcdc would allow. I had a 40 amp cb on the circuit and it tripped after camping for a day and a half, (engine running), so the bcdc does put out or draw 40 amps. Plus the aux batteries sit at 13 volts after being charged by the car or solar. That can be a week or two later. It seems to be a great system. I used Cuppa's knowledge to set this up and he is right on the money with his advice. Good luck.

[the evil twin]

Hiya Cuppa


Ummmm, yes it can

[QUOTE]

Uummmm, no it can't, not unless you have about a 500 watt or larger solar array

The BCDC cannot make something from nothing so if the max output of the solar is say 6 ish amps from say a 100 watt nominal array then that is as good as it gets.

The BCDC will sacrifice current to raise the charge voltage IE say, 12 volts in at 5 amps (60 Watts) will give you say 14 volts out at 4 amps (approx 55 watts after internal losses).
You can't feed less power into the DC DC device than you can get out

[QUOTE=Cuppa;563137]
[/COLOR]
I don’t really understand this. I know that there are recommendations of charging amps, generally around 10% of the battery’s capacity in amp hours, but if the battery is being ‘well looked after’ it will generally be getting charged before it is ‘over discharged’ & consequently the battery will only accept a lower charge rate regardless of the capability of the charger. The BCDC won’t force 40 amps into a battery any more than straight alternator charging would.

Yep, totally agree the charge acceptance rate is determined by chemistry and SOC of the battery but not all deep cycle batteries can handle the max current at the charge acceptance and rely on voltage limited current regulated charging.
Again, a quick check of the specs will make sure all is good.

As per the prev Q as well about AGM's under bonnet.

Quite a few of the Full River deep cycle batteries are spec'd for small charging currents (in the case of mine less than 20 amps)
They are also spec'd for lower ambients than in an Engine
We got a good buy on a heap of them at our Club a while back.
Mine are still going gangbusters after nearly 4 years in the camper
A few of the guys who put them under bonnet killed them in under 12 months

Equally tho, Full River do make versions that will take higher current.
Some manuf only make one or the other and some make both

[farqman]

Ummmm, yes it can


[/COLOR]
I don’t really understand this. I know that there are recommendations of charging amps, generally around 10% of the battery’s capacity in amp hours, but if the battery is being ‘well looked after’ it will generally be getting charged before it is ‘over discharged’ & consequently the battery will only accept a lower charge rate regardless of the capability of the charger. The BCDC won’t force 40 amps into a battery any more than straight alternator charging would.


I think the problem is if the battery is flat the Redarc pumps a full 40a into the battery. A lot of manufacturers recommend 20-25amps.

I got the Redarc to fully charge an AGM battery, and to account for the different chemistry. Perhaps just got the wrong one. Maybe should have bought the BCDC1225 instead. Too late now I can't return it.

As for heat in the engine bay I was planning to mount it between the grill and radiator like a member from another forum. Will get plenty of airflow here.

http://i272.photobucket.com/albums/jj200/benwilson1/aef13e11be392221aa576412f0c34950.jpg

[farqman]

I am thinking I may end up going down this path

http://i272.photobucket.com/albums/jj200/benwilson1/d1555fa7fd3b08f915f1d6dc59e9a6f8.jpg

[threedogs]

I've spoken to they guys at Alco batteries down my way, they will sell me a sealed battery but wont install it for me.
Its all about one battery exploding and the damage it will cause. they aren't going to pay for it. not sure a heat shield is the answer.
They had no problem installing a Vulcan wet cell 115 AH AUX battery for me. Most batteries have explosion caps on them, but if it
starts to swell I'd be removing it.
You just need to look at those Pics NN put up with the turbo glowing, that a lot of underbonnet heat'

[Cuppa]

Uummmm, no it can’t, not unless you have about a 500 watt or larger solar array

Ah yes, you are of course correct. I chose the BCDC1240 because I have 425w of solar in my Patrol , (& many folk I know with rv’s have similar or more). The batteries are Ritar DC series with a max 36 amp charge rate. With the SoC I maintain I have never seen more than around 20 amps coming in, mostly far less.

I did qualify my statement about charge acceptance by saying ‘if a battery is being well looked after’, by which I meant not being discharged to the point of accepting higher than specced charge rates. As I typed it I guess I was thinking that anyone who bought good batteries & an expensive dc/dc charger to go with them would have (should have) put enough thought into what they were doing to have a balanced system resulting in never, or rarely allowing their battery(ies) to become severely discharged. I suppose this might be a rather optimistic thought & upon reflection suppose that many 4wd’ers do only have a single aux battery & don’t buy a BDCD1240 for it’s 40 amp solar charging capacity. Also that many people do not ‘treat their batteries well’ as I advocate. Therefore your advice that they ensure the compatibility of their battery with the charging rate (when severely discharged) is wise. However such use is unlikely to have the benefit of long battery life that a balanced system ensures. Alternatives are to use a lower amperage BCDC or just to rely on solar to do the topping up to full without a dc/dc charger at all. Or to have a set up which allows direct alternator charging up to a pre-set state of charge with a lower amperage dc/dc charger to ’top up’ the battery to a full state of charge. Or a mix of both. Again intended usage patterns would dictate which would suit best.

Thanks for the feedback on the early demise of the Fullriver AGM’s under the bonnet. If your Fullrivers are HGL series (max charge current 20 amps) they should still keep going gangbusters for at least another couple of years, maybe more. Fullriver DC series can take higher charge rates (up to 100amps I think) & importantly also have a construction which withstands vibration better, these if treated well will give a lifespan of 10+ years. I have only ever had DC series Fullrivers. A friend with HGL’s in his OKA was disappointed when they karked it at around 6 years old a couple of years ago (not under bonnet), prior to this he (& I) had thought all Fullrivers were much of a muchness.

[Cuppa]

I think the problem is if the battery is flat the Redarc pumps a full 40a into the battery. A lot of manufacturers recommend 20-25amps.



Will be fine if you get a battery which can accept 40 amps. (e.g.. Fullriver DC series). If you expect to be using a battery until it is ‘flat’ you are probably wasting your money whatever you install. If you intentend to (sensibly) not let your battery become discharged below 40% to 50% SoC then Ritar DC series or others similar (with charge rate of 40 amps or close to it will be ok).

[Cuppa]

I am thinking I may end up going down this path

http://i272.photobucket.com/albums/jj200/benwilson1/d1555fa7fd3b08f915f1d6dc59e9a6f8.jpg

I guess it really does depend upon what you are wanting to achieve. If, for example, you wanted to run the same loads off both aux batteries in that set up you would need a changeover switch of some sort to allow each to supply te load independently. If that was the intended usage however, then unless space dictates otherwise I can’t see any advantage over having both aux batteries in the rear of the vehicle & not needing the SBI12. However if for example, you wanted one of the aux batteries specifically to provide additional capacity for winch use (paralleled to start battery as shown) this setup would make more sense. If the latter, I would probably still utilise a changeover switch to allow use of both batteries for regular ‘camping loads’ if winch use is generally going to be a rare event.

My vehicle had an under bonnet aux battery when I bought it, set up with an SBI12 but when I installed batteries in the rear I chose to remove the under bonnet aux & instead run heavy cables between start & rear aux batteries which I can manually parallel with the start battery for winch use or in the event that I ever need a jump start. It also enables me to direct charge the aux batteries from the alternator if I were to choose to do so, & means that I can also connect a mains charger to the start battery to charge all the batteries at once (an advantage for me because the under bonnet start battery is easier to access than the rear AGM’s).

Ps. have sent you a PM

[the evil twin]

I am thinking I may end up going down this path

http://i272.photobucket.com/albums/jj200/benwilson1/d1555fa7fd3b08f915f1d6dc59e9a6f8.jpg

Cuppa has raised some good points above and further to those whilst assuming that the Aux is a Full River DC series or equiv and mounted under bonnet in that diagram...

The DC series is a Deep Cycle AGM rated for Cranking duties so to get the bets use and versatility I would suggest the following

I would use 2 B&S between the Under Bonnet Batteries and the SBI12 with 150 Amp Fuses.
I don't see any point in light gauge wire/small fuse ratings between cranker rated batteries
1. A switch or whatever in the Redarc fly lead will then allow you to start off the Aux at the flick of...
2. Whatever size cable you do end up using determines the size of the Midi Fuses
3. If you have a winch use the 200 Amp Redarc or an Intervolt/Projecta/etc that handles 150 to 200 amp continuous and up the Fuses accordingly.
4. I also prefer the SBI12D or Intervolt equivalent over the SBI12 because the dual sensing comes in handy and simplifies charging of the under bonnet batteries but again no biggee.

If you fuse the power input at the BCDC (no fuse shown on the dia) the 60A Midi at the starter for the BCDC feed should be determined on the cable size running to the BCDC normally it will be around 6 to 8 B&S or so and then a BCDC power input fuse no higher than 40.

If you don't fuse the power input then the 60 Midi should be no higher than 40 Amp.

I don't really understand why the use of the Relay in the circuit is so popular but if you want to use it then OK.
1. The BCDC will isolate the starter at 12.7 volts so it provides no extra protection in that regard.
2. If you connect a power source to the vehicle batteries, say Solar or Charger it cannot power the BCDC unless Ign is on
3. The Solar Panel pictured can't charge the Under Bonnet batteries (I favour feeding the vehicle Aux for Solar and let that power the BCDC if the 2nd Aux is also on board)
4. If you have a Solar array that is always available (hard mounted to your truck for example) it is taken out of circuit if the ignition is on and all loads are now on the Vehicle electrics
5. If you aren't hard mounted and have to deploy your array at Camp or whatever then the vehicle Ign is off anyway.
6. It is another bunch of crimps/connections etc which can fail, cause voltage drop or otherwise be a PIA.
7. If you have on board Solar it makes more sense to have the Relay control blue so it is relaxed to vehicle Ign and powered if Solar is available

None of the above is "you must".
It is just a few thoughts because I like to keep electrics as simple as possible while getting the best performance and most versatility out of any gear

[Cuppa]

I don't really understand why the use of the Relay in the circuit is so popular but if you want to use it then OK.


Just ‘automating’ the switching between solar charging of Aux batteries & alternator charging. Solar only charging if ignition is off. Redarc have a ’thing’ about not mixing charging sources. Probably more to do with simplifying fault finding with some of their other more complex electronics than necessity. The BCDC is either/or, not ‘and’. Having succesfully charged batteries through a combination of alternator charging AND solar charging concurrently for years without problem I must admit I found Redarc’s approach a tad over cautious. (Likewise their non temperature compensated 13.3v float charge on the BCDC1240 but that’s another issue).

[farqman]

Thanks Cuppa for the PM. All I can say is wow.

I purely bought the BCDC1240 because it was top of the range. Figured bigger is better. Learnt that's not so much the case.
The missus got me an ARB battery tray for Christmas (well ordered one, don't have them in stock). So I kind of need to utilise it. I didn't quite realise that charging at 40amp was such a big deal. Originally I was looking at the Optima range which doesn't have a limit, but found out they are quite small in capacity.

At the moment I will only be running a brand new Engel 40l. Plans in the future are to run another engel, inverter, possibly a water pump, and was thinking an Anderson plug in the rear, and one externally on the towbar in case I ever go down the camper trailer route. Also plan on using solar.

[the evil twin]

Just ‘automating’ the switching between solar charging of Aux batteries & alternator charging. Solar only charging if ignition is off. Redarc have a ’thing’ about not mixing charging sources. Probably more to do with simplifying fault finding with some of their other more complex electronics than necessity. The BCDC is either/or, not ‘and’. Having succesfully charged batteries through a combination of alternator charging AND solar charging concurrently for years without problem I must admit I found Redarc’s approach a tad over cautious. (Likewise their non temperature compensated 13.3v float charge on the BCDC1240 but that’s another issue).

Hi mate,

Yeah I agree with you and I guess Redarc could be concerned about bucking power supplies or frying the auto voltage sensing circuit or damaging the MPPT or somesuch.
My best guess is that it may simply be that if the voltage sensing sees a Solar panel it will think it is a 24 volt Alternator so for Solar it must be floating or grounded... who knows

What gets me is why the hell did Redarc design a +$400 bit of kit with an onboard MPPT Solar Reg and then have to rely on people wiring up external switching to select between Alternator and Solar.
1 extra connection and maybe $5 worth of solid state switching circuitry inside at point of manuf and it would have been fully automated in the device, heaps more reliable and easier to use.

It's like designing a car without any plumbing for the fuel tanks and saying "let the customer sort it out whether he wants Main, Sub or ability to switch between both".

[Cuppa]

Hi mate,

Yeah I agree with you and I guess Redarc could be concerned about bucking power supplies or frying the auto voltage sensing circuit or damaging the MPPT or somesuch.
My best guess is that it may simply be that if the voltage sensing sees a Solar panel it will think it is a 24 volt Alternator so for Solar it must be floating or grounded... who knows

What gets me is why the hell did Redarc design a +$400 bit of kit with an onboard MPPT Solar Reg and then have to rely on people wiring up external switching to select between Alternator and Solar.
1 extra connection and maybe $5 worth of solid state switching circuitry inside at point of manuf and it would have been fully automated in the device, heaps more reliable and easier to use.

It's like designing a car without any plumbing for the fuel tanks and saying "let the customer sort it out whether he wants Main, Sub or ability to switch between both".

Yep. Mind you the whole idea of a sub tank which needs to be pumped into a main tank seems like a pretty strange idea to me! I would much prefer separate pumps on each tank allowing fuel to be used directly from either tank & a dasboard switch to choose between them. :)

There has been debate recently on another forum about Redarc choosing to restrict the float voltage on the BCDC1240 to 13.3v instead of incorporating temperature compensation into the unit. (Redarc have confirmed that this is what they have done ... http://www.redarc.com.au/forum/discussion/219/bcdc1240-float-voltage#Item_2 you may need to sign in to read it) Most batteries have a specified float voltage of 13.6v to 13.8v & much as I like the BCDC1240 it does strike me as pretty ‘cheap’ to leave temperature compensation out of the package.
The other forum debate revolves around whether it is harmful to have the batteries floated at a lower voltage than the battery manufacturer specifies. One person in particular is adamant that it will reduce the battery’s lifespan whilst others suggest that as long as the float charge is above the nominally 100% SOC charged voltage all will be well. I’m hoping the latter are correct, but nevertheless feel a tad miffed that temp comp, something I consider quite important was left out of a ‘high end’ dc to dc charger. I find it a bit hard to believe that the decision to do so was simply a cost cutting measure, but cannot think of any other explanation.

[the evil twin]

Maybe they needed the money to be able to afford to buy Autron... :-)

[macca]

A bit of a review of our set up.

We have a 120 watt folding panel, an input meter, a BCDC1240 Redarc and 2 super start agm 105 amp hour batteries.

The Ute has been parked for 3 1/5 days.

The weather has been mainly overcast and cool. So the fridge has not been working hard, nor have the panels had a lot of good sun.

This morning the solar was connected in good sun, the BCDC charged on boost (4.6 amp) for about 5 minutes, next time I checked it was on float (0.2 amp).

This system is working as designed, even when overcast the system goes to float mode and keeps the batteries fully charged.

This means we can easily camp for more than a couple of days without worrying about camp power.

Very happy with this set up, and a special thanks to Cuppa for his advice.

:D I would go as far as saying this is a 5 star system, cost a bit to set up but I wasted a lot on the previous systems that we discarded. Would have been a whole lot smarter to do this the first time. We live and learn.

[Cuppa]

We are sitting at camp on the shore of Lake Burrumbeet. Fridge (60l) is running at -2 & freezer (35l) is running at -19. (Gotta keep the ice cream hard!). The laptop is charging & we are listening to music. We have no battery currently in the Tvan, so last night I utilised our solar cable to supply power to it from the Patrol. This meant that the solar didn't get plugged in until I got up at 8am. By 10am the batteries were fully charged & floating. 360ah battery capacity. 300w solar (the 125w rooftop pane is in shade). Most amperage I saw coming in was first thing at 8am - 13amps which dropped down to 5 amps after a short time, still in good sun with clear sky. Prior to connecting solar this morning, with freezer cycling on battery voltage was 12.6v. Rose to 14.5v before dropping back to float at 13.3v. This system is designed for indefinite self sufficiency & to accomodate a minimum of 1 week’s poor solar weather.
Photos would have been better with my camera but I left the transfer cable at home, so these were taken with the iPad.

[macca]

Knew yours would work faultlessly. :cool: