Redarc Trailer Charger mounted inside the Ollie for 100% lithium charge

[John E Davies]

I peeled this off another thread about the need to isolate the higher voltage of the lithium batteries from the truck to prevent “back feeding”, one owner noted a continuous 5 amps😳. I am pretty sure it would work fine with the 20 amp fused charge wire already installed in the trailer harness but I would appreciate confirmation of the Ollie fuse and wire size. This device requires a 15 amp fuse on that input, and the max draw is only 11 amps (for a 12 volt system).

This won’t flow a huge amount of amps to the batteries like other alternatives, but it should be plug and play for most tow vehicles; only a smart “variable voltage” alternator would require you to run a small sense wire up to the engine bay. All regular TVs don’t need that, it simply senses the rise in voltage when you start the engine and ten seconds later it switches itself on. Very cool, I think! It will charge lithium’s to 100% which is what I am after. Otherwise my Land Cruiser system probably won’t be able to get it over 70%. During sunny weather the rooftop solar should be enough, but I don’t want to completely rely on that in night time or gloomy weather.

“The BCDC1212T is specifically designed for, but not limited to, applications where the input current required to charge a trailer mounted auxiliary battery is drawn through the vehicle’s towing harnesses and connectors. It limits the input current drawn to 12A which provides for safe and reliable operation when using towing harnesses, fuses and connectors that are suitably rated without the need to install additional cables and connectors between the start battery/alternator and the BCDC1212T/auxiliary battery.
The BCDC1212T is a three-stage, 12V DC-DC battery charger that operates from an alternator input of 12V or 24V. The input voltage to the BCDC1212T can be above, below or equal to the output voltage making it ideal for charging an auxiliary 12V battery where the distance from the start battery or alternator may cause a significant voltage drop. When connected to a 12V alternator the BCDC1212T will typically provide peak boost currents of 11A.
The BCDC1212T isolates the start battery from the auxiliary battery, to avoid over-discharging the start battery.“

https://redarcelectronics.com/products/trailer-battery-charger

Instruction Manual pdf

Excellent install video here at eTrailer.com:

https://www.etrailer.com/Battery-Charger/Redarc/RED96FR.html

They do caution that the lithium batteries must have a built in battery management system, which most RV batteries do (home brewed battery banks may not). I emailed the dealer I ordered my new Victron batteries from to confirm it would be OK to use this.

So, are there any reasons this would not be a good choice? The fact that it is mounted on the trailer is really good in case you change TVs, or if you sell the trailer it will be useable by the next guy with little or no fuss. I think the 11 amp charging limit is acceptable for most people if it allows them to get close to a full charge during a typical drive. If you have 400 amp hours of batteries (the factory setup) that are severely depleted, there is no way it will bring them up to 100% on a single days drive; that is why you carry a generator so you can use the high charge rate of your standard converter. I plan for just two 100 amp hour batteries, using 80%, so I think this would be quite helpful. At the very least, it provides an easy fix for the isolation problem some owners have.

Comments please.

John Davies

Spokane WA

Edited December 1, 2020 by John E Davies

[NCeagle]

I think DC to DC chargers are one of the best options if feasible.  Do you have a way to get back to the Oliver batteries with 8 gauge wire already?

[mjrendon]

Hopefully this link will answer some of the questions raised and likely raise others. 

 

Edited December 1, 2020 by mjrendon

[John E Davies]

1 hour ago, NCeagle said:

I think DC to DC chargers are one of the best options if feasible.  Do you have a way to get back to the Oliver batteries with 8 gauge wire already?

I agree that is "best" in terms of being able to handle 30 or 40 amps DC continuously, but not at all best in that you have to modify your existing tow vehicle, run huge wires with huge fuses and connections, which is always a major hassle, and then do the same for the Ollie. You could punch a hole in the hull below the propane bottles next to the factory wires and then run the new cables under the vanity and along the waste system to the battery area. Doable, but hardly an easy solution. Big cables, big connectors and big fuses are expensive and require special tools to fabricate. Then you trade in the truck and you have to do it all over again for the new one. And when you sell the Ollie the new buyer looks at that extra cable on the tongue and says "What the heck?". You either take a loss on the cost of all the installed equipment, or you yank out the electronics, leaving all the cables in place, to reuse on the new truck installation. You will always have the extra hassle of a large cable pair carrying a high current on the trailer tongue, and you need some safe location to plug it into near your back bumper. 

If you can provide your own tools and skilled labor, it may be a good approach, but if you have to pay for 5 or 10 hours of shop labor, probably not. They won’t quote you a price, it will be “time and materials”, and you just have to hope they don’t work slow or run into bottlenecks.

OTH it should charge the factory Ollie lithium package very well. So, I guess “best” is determined by your purse size, battery bank size, solar conditions, and your priorities.

I think the really big advantage of this Redarc unit, other than ease of installation, is that you can say to a buyer, “Sure, it only gives you 11 amps, but it is a high quality charger, it protects your truck’s electrical systems, and you probably won’t even need to a small sense wire to the engine bay. If you do, it might cost $100 including labor.” It is better than telling them, “To get this to work you need to install a whole bunch of expensive specialty equipment on your TV.”

John Davies

Spokane WA

 

Edited December 1, 2020 by John E Davies

[mjrendon]

How about a $50 300 watt pure sine wave inverter from the truck to the generator port on the front of the Oliver?  

Edited December 1, 2020 by mjrendon

[John E Davies]

1 hour ago, mjrendon said:

How about a $50 300 watt pure sine wave inverter from the truck to the generator port on the front of the Oliver?  

My onboard Progressive Dynamics charge converter itself draws 725 watts, around 6 amps AC. If you flipped off all the other circuit breakers you might be able to get by with a 1000 watt inverter. But if any other circuit was live and drawing power, like the microwave, then it would not carry the load. Regardless, going from DC to AC and back to DC to charge batteries is really inefficient. And that 1000 watt inverter would need a 6 AWG supply cable.

John Davies

Spokane WA

Edited December 1, 2020 by John E Davies

[bhncb]

47 minutes ago, mjrendon said:

How about a $50 300 watt pure sine wave inverter from the truck to the generator port on the front of the Oliver?  

https://www.airforums.com/forums/f449/charging-lithium-batteries-from-our-tv-217112.html

[John E Davies]

On 12/1/2020 at 11:06 AM, bhncb said:

https://www.airforums.com/forums/f449/charging-lithium-batteries-from-our-tv-217112.html

Edit 10/16/22, in case that link disappears.

Yikes!

He mounted a 2000 watt (surge) inverter in the engine compartment; these units will shut down at temps above around 150 degrees F. The heat is really bad for them. And no way is that unit OK for a wet environment like that. Zap!

He ran a 120 VAC 16 AWG live household extension cord past the engine, exhaust and under the truck chassis!

The first is just poor planning, the second is super dangerous and against all kinds of codes and logic. I did not read any further, this is criminal. Please do not do this.

John Davies

Spokane WA

 

[bhncb]

2 hours ago, John E Davies said:

The first is just poor planning, the second is super dangerous and against all kinds of codes and logic

When I first started reading this I though it was a joke. Then the pictures downloaded.

[Overland]

2 hours ago, John E Davies said:

He ran a 120 VAC 16 AWG live AC household extension cord past the engine, exhaust and under the truck chassis!

Makes me wonder about those Airstream owners.  He even got complimented for having 'thought everything through'.  If I run into that particular Darwin Award applicant at a campground, I'll have to remember not to touch his truck or trailer - that could be a nasty shock.  

[bhncb]

18 minutes ago, Overland said:

 He even got complimented for having 'thought everything through'.

I read that as more of a facetious response. In spite of their choice, most riveters are capable of seeing the dangers of  this setup.

[John E Davies]

1 hour ago, Overland said:

Makes me wonder about those Airstream owners.  He even got complimented for having 'thought everything through'.  If I run into that particular Darwin Award applicant at a campground, I'll have to remember not to touch his truck or trailer - that could be a nasty shock.  

OTH, there was a thread here about how to add extra security to your Ollie when boondocking. I think this would qualify, as long as the owners remembered to wear non conducting gloves and shoes. Keeping the frame and steps juiced up with 120 volts AC might deter a bad guy or even a bear.... 😜

John Davies

Spokane WA

Edited December 1, 2020 by John E Davies

[BackofBeyond]

Ok, a question - Why is the new Li Oliver system not designed such that this issue is not - an issue. Seems like an engineering error - omission. The Dc to DC is a cheap - simple solution - similar to what I did on my last van conversion. 

[John E Davies]

52 minutes ago, BackofBeyond said:

Ok, a question - Why is the new Li Oliver system not designed such that this issue is not - an issue. Seems like an engineering error - omission. The Dc to DC is a cheap - simple solution - similar to what I did on my last van conversion. 

That is a very good question, why don’t you ask the Mother Ship about it? I think it deserves its own thread. Their lithium packages seems to be a work in progress at this time. Way WAY big battery capacity, but the other side of the equation- how to recharge all those amp hours once it gets depleted - has not been figured out yet. I see no point in a huge battery bank if you can’t get it recharged without plugging into shore power or running the generator every other day. 

I do think that something like this Redarc charger, an onboard unit that has the ability to take the batteries to 100%, not 70%,, should be a fundamental part of the lithium package. As should be a more efficient solar charge controller. Every little improvement helps the overall package..

John Davies

Spokane WA

[mjrendon]

58 minutes ago, BackofBeyond said:

Ok, a question - Why is the new Li Oliver system not designed such that this issue is not - an issue. Seems like an engineering error - omission. The Dc to DC is a cheap - simple solution - similar to what I did on my last van conversion. 

I think that most of the existing lithium based Oliver trailers were not designed by Oliver engineering.  Should there be accountability on Oliver's part if the owner changes battery chemistry? 

I believe there is at least one Oliver lithium based system out now.  Do the same issues exist on any systems designed/released by Oliver?  

[SeaDawg]

3 hours ago, John E Davies said:

Keeping the frame and steps juiced up with 120 volts AC might deter a bad guy or even a bear.... 😜

Reminds me of one campground we stayed at in the Yukon. They had an electrified bear fence around the tent camping area...

(Congdon creek, yt. Free firewood. $12 a night, Canadian. Beautiful spot, but keep your campsite clean and clear.)

Edited December 2, 2020 by SeaDawg

[SeaDawg]

2 hours ago, BackofBeyond said:

Ok, a question - Why is the new Li Oliver system not designed such that this issue is not - an issue. Seems like an engineering error - omission. The Dc to DC is a cheap - simple solution - similar to what I did on my last van conversion. 

I suspect it's a bit more complicated  to do b2b/ dc to dc, as it requires modification to the tow vehicle as well? Oliver can warrant their own production, but modifying your truck, with current electronics,  is another story. (My costco store won't even install batteries, anymore. Just sells them in the automotive store. Probably for the same reason.)

In a van conversion,  it's all in one. Short distance,  one vehicle involved?

Just for more reading material, I  found this great article about adding dc to dc/ b2b capability to a 2016 Ford f150, employing an aussie version of the redarc uniy John Davies discovered.  Comes with this warning: 

Disclaimer: Mistakes in the electrical system can cause fire, injury or even death. If you have any doubts about working with electricity in your RV, consult with a professional electrician.

https://www.adventurousway.com/blog/rv-electrical-upgrade-part-3-dc-charger-truck-12v-socket

 

Since I understand about 85 per cent of it on the first read, I'll let you guys poke holes. Especially in light of newer vehicles. 😁😁😁

 

 

 

Edited December 2, 2020 by SeaDawg
Multiple typos... it's late, and I've had a glass (or two) of wine.

[John E Davies]

44 minutes ago, SeaDawg said:

I suspect it's a bit more complicated  to do b2b/ dc to dc, as it requires modification to the tow vehicle as well? Oliver can warrant their own production, but modifying your truck, with current electronics,  is another story. (My costco store won't even install batteries, anymore. Just sells them in the automotive store. Probably for the same reason.)

In a van conversion,  it's all in one. Short distance,  one vehicle involved?

Just for more reading material, I  found this great article about adding dc to dc/ b2b capability to a 2016 Ford f150, employing the redarc connector John discovered.  Comes with this warning: 

Disclaimer: Mistakes in the electrical system can cause fire, injury or even death. If you have any doubts about working with electricity in your RV, consult with a professional electrician.

https://www.adventurousway.com/blog/rv-electrical-upgrade-part-3-dc-charger-truck-12v-socket

 

Since I understand about 85 per cent of it on the first read, I'll let you guys poke holes. Especially in light of newer vehicles. 😁😁😁

 

That is a great article, I did not see anything wrong with what they did, it is just a really souped up version of the small Redarc unit I started this thread about. They just multiplied all the parts by about four times 😳. I don’t think I would do anything different, except I would run a dedicated ground wire all the way to the battery area, not just hook it to the frame in back to a bolt ... that can make problems years later from corrosion caused by stray currents moving where they are not supposed to be. I saw this and was impressed, I have never seen one of those hinged covers in the forty years I have been using Anderson connectors. I need to find a source.

Thanks very much for posting, I enjoyed the read....

EDIT: I found that cover and mount, it has to come from Oz, it isn’t sold here. “ the original version, not the rubbish from Asia.”😀 .... 

https://andersonconnect.com.au/store/index.php?main_page=product_info&products_id=58

John Davies

Spokane WA

Edited December 2, 2020 by John E Davies

[Jairon]

1 hour ago, mjrendon said:

Do the same issues exist on any systems designed/released by Oliver?  

I think most purchasers of the lithium package are interested in camping at locations without shore power and will basically always have a generator. The panels are just supplemental power. With this combo, you don't need to run your generator 24/7. You can simply run a tank of gas over 3-4 hours and then tear through your stored power with the generator off. I haven't done the math but a 2200x generator at 1800 watts and 15 amps should come close to charging a 400AH lifepo4 bank at 80% DOD in about 4 hours. Anyone that builds something like John is doing will have an additional source of power which is always nice to have.

SeaDawg pretty much nailed the reasons why Oliver doesn't offer something like this.

[SeaDawg]

JED, it gets really interesting if you read all the articles in the series,  and the comments.  

If you really want the Aussie version, it's attainable. 

I'm really sad that our Aussie camping trip was not possible this year. Our friends in Tasmania only got out a few months ago. First year they'd spent the winter in Tassie in almost 20 years.

2020, is what it is. 

[SeaDawg]

59 minutes ago, Jairon said:

think most purchasers of the lithium package are interested in camping at locations without shore power and will basically always have a generator. The panels are just supplemental power.

Probably true..

Not for us. We pretty much live on solar everywhere--home, Ollie, boat.  But, we've learned to manage power and water.  Second nature,  now.

We don't have lithium yet. That would really expand our parameters. I  keep studying.

We probably have another 3 to 4 years on our Agm batteries.  

Edited December 2, 2020 by SeaDawg

[Jairon]

14 minutes ago, SeaDawg said:

We don't have lithium yet. That would really expand our parameters. I  keep studying.

We probably have another 3 to 4 years on our Agm batteries.  

If you can sip power, AGM makes a ton of sense. Slow drain and solar can actually keep up with your usage. Keep studying and wait for some price drops! 😀

Some buyers/users might think of the lithium option as a "solar system" where I think of it more of a silent energy bank to beat up while the generator is off. The panels are just a small perk.

Edited December 2, 2020 by Jairon

[Jim_Oker]

I look at the Lithium option as a way to gradually wear away at the charge level while boondocking, topped off by solar or if necessary (I do live in the PNW...) generator now and then between opportunities to plug in. Based on our van battery usage w/o solar, I'm hoping we can still be sipping off the battery many days between plugging in to shore power or generator especially if we can get some sun on the solar panels. I am not thinking about it in the "must be back at 100% nightly" frame. It seems that between usable charge and lifespan even if this is somewhat harder on the batteries they should still last a decent while. edited to add: I don't mind running a generator now and then kinda like I don't mind doing laundry now and then but I don't want to be doing it daily for the most part.

As for the main thrust of the thread, I thought the concern was that merely plugging the trailer 7-pin to the TV was at least for one person (who maybe had a non-Oliver Lithium implementation?) was draining trailer battery charge out toward the TV. Given that I have chosen the Lithium/solar package for a unit that should be built any hour now I think I'll check to see what the fine service folks know about this with respect to the factory setup for the 2021 models (which is what's currently being built).

Edited December 2, 2020 by Jim_Oker

[John E Davies]

Well, I decided to order one. They don’t ever seem to discount the price, but eTrailer.com has it for $250, free shipping and a cool free Redarc hat. As a follically challenged older male, that cinched the sale.

My Land Cruiser puts out 14.0 volts, max, so I need this if I want any usable amount of charging from the truck while towing. The lithium batteries require 14.5 volts.

John Davies

Spokane WA

Edited December 6, 2020 by John E Davies

[mjrendon]

John, 

Are you going to use the 12v source from the 7 pin connector and place this Redarc unit inside the trailer?  

I have been pondering the Victron Orion  12-12-18, but  I can't make that work with the power available from the 7 pin connector.