Installing Renogy DC-DC charger in 2018 F-150

[FJR Colorado]

Thanks for posting. Interesting. Watch those grommet cops!

In my experience, I get a LOT more daily charge out of a 100W Renogy panel. More than enough to maintain a fridge/lights scenario.

But I may do a set up like this for my FJC. I won't put a solar panel on that because it is garaged.

 

[Martinjmpr]

Thanks for posting. Interesting. Watch those grommet cops!

In my experience, I get a LOT more daily charge out of a 100W Renogy panel. More than enough to maintain a fridge/lights scenario.

But I may do a set up like this for my FJC. I won't put a solar panel on that because it is garaged.

Just to be clear I meant 5 - 6a every hour. So on a sunny mid summer day with ~ 10 hrs of good sunlight call it 50A.

 

[Martinjmpr]

NEXT STEP DONE: Interior work!

I didn't want to start tearing the truck apart until I had an entire day but I got some tools and hardware from Amazon and was anxious to get some work done.

So today's project was getting the harnesses/connections from the DC-DC charger to the portable battery pack. I had some 8AWG cable around and a brand new crimper I was itching to try out. I also had a set of Anderson connectors from a long-abandoned project. My thought was that since my setup needs to be fully removable, I didn't want to have the battery pack hard wired to the DC-DC charger.

First step was to figure out how long my wires needed to be. For obvious reasons I want them 'long enough" but no longer than neccessary. This is a mock-up of how we travel. The clear box closest to the camera is the food box. Fridge sits in the middle (so wife can reach it while I'm driving.) and the battery box sits in front of the food box, nice and tightly so nothing moves around.



The space on the other side of the fridge, i.e. the area behind the front passenger seat, is where our dog rides on her dog bed.

Obligatory dog picture:




Of course, that was when she was a puppy and at maximum cuteness but she's still pretty cute.

Next step was to make a "short" harness to attach to the battery pack, and fit it with one end of the Anderson connector:



And another one for the charger end:



I had some wire loom around so I prettied it up with wire loom and then mocked it up in the truck



When not in use the cable will be coiled up like this and the charger disconnected at the battery (by removing the fuse)



I'm pretty happy with how it looks, will do the hard work on the truck this weekend!

 

[Martinjmpr]

Well, it's done and seems to work fine. No real issues with installation, just a time consuming process.

Attention "grommet cops":



Ran the wires alongside and above the frame and secured it with zip ties wherever I could. 3/4" wire loom was kind of cumbersome, I probably COULD have gotten by with 5/8.



This is the attachment at the battery end. I was trying to figure out how I could disconnect the power when not using it and then I looked into my box of "unused crap" and found this post-mount battery disconnect switch that I bought 4 years ago for a different project and never used. Now all I have to do is unscrew the knob when I don't want the charger to be energized. I'll keep the knob in the console of the truck.





Green light on - it works!

The only issue I had was finding a fuse to connect the add-a-circuit to that was only "hot" when the ignition was on. But once I did that it was done. Took it out for a drive (with a partially discharged battery and the fridge on a warm day) to see if it charges and it seems to charge very well, measured 14.4v coming out.

 

[luthj]

Looking good. My only suggestion is that you may want to support that disconnect which is hanging off the terminal fuse. I have seen those fuses fail from vibration when there is a good moment arm attached.

 

[Martinjmpr]

Looking good. My only suggestion is that you may want to support that disconnect which is hanging off the terminal fuse. I have seen those fuses fail from vibration when there is a good moment arm attached.

OK, silly question maybe but could I not achieve the same thing by simply switching places between the disconnect and the terminal fuse? IOW bolt the disconnect onto the battery terminal and put the terminal fuse on the "far" end of the disconnect? Any reason why that wouldn't work?

EDITED TO ADD: Or another option, rotate the disconnect 90 degrees counterclockwise so it's directly above the battery casing, and then put some non-conductive supporting material in between the disconnect and the battery casing (maybe foam of some type?) Perhaps held in place with double-stick tape?

 

[luthj]

EDITED TO ADD: Or another option, rotate the disconnect 90 degrees counterclockwise so it's directly above the battery casing, and then put some non-conductive supporting material in between the disconnect and the battery casing (maybe foam of some type?) Perhaps held in place with double-stick tape?

That would be my first suggestion. HDPE cutting board, painted wood, etc.

 

[Martinjmpr]

Just thought I'd do a quick update on this. Have had the Renogy DC-DC charger/12v aux battery box setup on 3 different camping trips so far, and it's worked well. Battery has really never fallen below maybe 75% capacity because it seems like we drive somewhere for a few hours every day.

Having said that my current system works, if I was doing it today I'd be more likely to go with an all-in-one plug-and-play solution like the Rockpals 500W portable generator. With a Li-Ion battery, built in charger and even an inverter (something my current setup doesn't have) it's a nice solution to the need for extra power to run something like a fridge. Really, my current setup is overkill for what I'm doing, a portable battery like the Rockpals would be just as good, and much smaller and lighter.

The prices on these battery packs have been steadily dropping as well. The Goal Zero and similar packs were ~$800 when I started this project which is what prompted me to make my own jury-rigged version. But you can now get similar ones in the $440 range.

I would estimate my total expenses so far to be as follows:

Minnkota battery box (Amazon): $65
90ah wet cell group 27 battery (Costco): $90 + $15 core charge, $105 total
Renogy 20a DC-DC charger (Home Depot): $120
12v USB port and digital volt meter (Amazon): $15
25' of 8g double wire (Amazon): $23
Hyclat Anderson connector for battery (Amazon): $10
30a terminal fuse block and fuse (Amazon): $28
Crimping tools, grommets, etc (Amazon): $48
Terminal mount cutoff block (Amazon): $8
Assorted wire and connectors (various): $20

That totals up to $442 and doesn't take into account any of my time (probably 10 - 12 hours altogether, although I work very slow.) For that much money plus a few clicks of the mouse I could have had a ready-made solution as well and it likely wouldn't (a) require me to drill a hole in my truck (for the wire) and (b) wouldn't weigh 75lbs like my current battery box does.

On the plus side, 20a is a quite a bit more power to charge the battery with than could be pulled through a cigarette-lighter type of connection, so there's that. And of course if I ever got the inclination to do so, I could substitute a much lighter Lithium battery which would significantly reduce the size of my current setup.

Still, what I have is 'good enough for now' so I'll likely run with it for the present.

 

[MagicMtnDan]

Great thread(s), thanks!

Forever is how long I've been thinking about building a battery box. I had a dual battery system I installed on my old Chevy pickup and since then I've been hooked. Now I have a Jeep Gladiator and a Ford Raptor so I don't want to invest in 2 dual battery systems.

Having a portable house battery box I can use in both vehicles would be ideal.

Only question I think I have now is, did you consider (is it a good idea) to put the DC-to-DC Battery Charger into the battery box so it goes with the battery in one unit? I understand it makes the battery box bigger and heavier but for me it sounds better on paper anyway.

Thanks again!

 

[dstefan]

+1 on this ^

thinking the same thing, but with a RedArc 25. Thinking RedArc in the box w/ a BattleBorn 100ah with an inverter mounted on top of the box and probably a thermostat activated computer fan. Crazy?

 

[vomhorizon]

+1 on this ^

thinking the same thing, but with a RedArc 25. Thinking RedArc in the box w/ a BattleBorn 100ah with an inverter mounted on top of the box and probably a thermostat activated computer fan. Crazy?

Red Arc makes a really good DC-DC and I too was considering it for my build at one point but kind of figured that a non-engine bay application probably doesn't warrant the extra cost given other excellent choices out there (particularly the app-connected Victron DC-DC smart chargers). $ for $ that money (in my case) was better spent in buying a better battery, solar panel and other components..

 

[dstefan]

Good point! I do really like Victrons app — been using their cheapy stick on battery monitors on my dual set up. The solar combo of the RedArc is kinda persuasive though, and then use the Victron 712 w/ shunt was what I was thinking ?

 

[vomhorizon]

Good point! I do really like Victrons app — been using their cheapy stick on battery monitors on my dual set up. The solar combo of the RedArc is kinda persuasive though, and then use the Victron 712 w/ shunt was what I was thinking ?

That would be a great combination. The only problem I had with a DC-DC and an MPPT combined was the lack of flexibility in upgrading or being left in the dark when (if) something goes wrong with the device. With the victron duo you get a 30A DC-DC, and a 15A MPPT all for about $350 and both can be monitored and programmed with the app. Red Arc is the best solution for dealing with the harsh engine bay environment, but if you are mounting it inside the vehicle in a relatively benign environment then that may no longer be an area to pay a premium for. Same with coming to dealing with a sealed unit (Red Arc) which looks attractive for an engine bay but a pain to wire if you don't need that protection. Renogy has a new combined DC/DC and MPPT as well but again you are placing your bet on one device working and not dying on you killing 2 of your 3 potential charging options while you wait/deal with a warranty. I ended up going with a cheap Renogy DC-DC (the 20A standard) and it works just fine but in hindsight I would have liked to have gone for the Victron 30A.

 

[dstefan]

I like the concept, but am confused on the Victron duo. What I can find on it says it’s a PWM dual battery solar charge controller, not a dc-dc combined? Is there some new unit I’m not finding? Part of the RedArc appeal to me is that Victron systems for dc-dc seem overly complicated in my researching.

Found this on Victrons community that seems helpful. Scroll down a few posts and theres a good description of a combined system in a portable box, so were really not off topic to the portable issue!

Orion-Tr as 'solar' input of smart solar 100/20 - VictronEnergy

community.victronenergy.com

 

[vomhorizon]

I like the concept, but am confused on the Victron duo. What I can find on it says it’s a PWM dual battery solar charge controller, not a dc-dc combined? Part of the RedArc appeal to me is that Victron systems for dc-dc seem overly complicated in my researching.

The Victron units are pretty straight forward to wire up. An input side and an output side for your DC-DC and I think you can even wire up an ignition on connection just like you can on the Renogy, or the Red Arc for that matter. All connections are standard terminal crimps and no soldering required. The MPPT likewise is the same with a PV side and a Batter (output/input) side which plugs into the source you are charging. Just make sure you don't disconnect the battery connections while the PV is powered (there is a toggle in the app that allows you to shut down solar charging which is great if you want to disconnect the battery while leaving the panels still plugged in). If you use other products, like a smart shunt etc you can link up these devices within a network. All using the app which also allows you to customize (user defined) settings. The Victron app has a demo view where you can play around with settings on their products. On the DC-DC, much like their MPPT, you can set your absorption and float voltage. This is also the case with the Renogy 20A DC-DC, though there you have DIP switches and are thus limited to jut a few presets. I believe the RA BCDC has a set 14.5 v setting for LiFePO4 whereas on the Victron you can set it to 14.6 for example if that is desired for your battery.

In my setup, I picked up a Renogy 20A DC-DC charger, a Victron Smart shunt, and an MPPT and still saved around $50 on what I would have paid for the BCDC1225 so I feel that if the application doesn't involve the heat, vibration and moisture of an engine bay there are other products out there that perform well and offer better value. Conversely, if you want to mount it in the engine compartment or if you are really tight on vehicle space and one an integrated one and done system then the BCDC1225 and particularly the Manager 30 may appeal to you for that application. Regardless, they are really well made from what I have heard so you can't really go wrong.