[daihung]

Hi all, I'm thinking of doing the same project. Installing a DC-DC charger in a near future for a LifePo4 battery upgrade on my camper. Initially I thought maybe to make life simple, just locate and pull the fuse for the 12v 7pin and just let the (to be installed in the future) solar panel charge the battery. However, for long term, I think a DC-DC charger will work better charging. One single 175 watt panel might not be enough to top off the Lifepo4. The reason I'm thinking of upgrading to a Lifepo4, possibly a 300ah single battery, is because I have a 12v DC only 4.5 cubic foot refrigerator. It draws 6amps when running.

Anyway, I read on this form that there are several ways to run this two +- wires. Some ran it under the car behind the shield and panels and some ran it inside the car. I'm not car expert. My knowledge of wire run in cars was installing a few backup cameras for my older cars to the license plate. All the cable tucked under rubber seals and maybe popped one or two side panels

I checked Robert's video. The run is inside the car on the driver side. It seems to be a good run but look difficult to pull all the panels. Underneath the car means I have to crawl under the car. The wires might be exposed to road salt and other stuff that can damage the wire. For an amateur, what is my best option?

Also, what kind of fuse and/or breakers do I need for this run? Any Amazon links? I'm trying to better understand what I need to do before buying all the parts.

Thanks so much.

 

[critical367]

I plan to use both portable solar panel (200W) (when staying in one spot through the day(s) and DC-DC charger (when overcast or driving to next spot) to meet my needs.

I thought the inside route was going to be better and slicker but then looked at the under car route and chose that as simpler and more than adequate. I chose 6AWG wire for my length (<25 feet from car battery to Renogy combined DC-DC and MPPT controller) and 30A. Two wires side by side are about 3/4".

Here is my list of stuff from Amazon: Check out my list on Amazon

The fuse and wire sizing are based on the instructions with the Renogy unit.

The wire insulation is silicone and should not be damaged by salt or dirt. I was able to get my head and arms underneath enough without having to raise the car. I bought some conduit to protect the wire, but having seen how it runs, I will only use that on the trailer side where the wire runs along the A-frame to the Anderson connector. I hope to finish it up this week and will post more photos.

 

[Robert.Mauro]

I plan to use both portable solar panel (200W)

Which one did you decide on?

 

[critical367]

Which one did you decide on?

Renogy 200 Watt Eclipse Monocrystalline Solar Suitcase w/o Controller | Renogy Solar

 

[daihung]

Hi Critical367,

Thanks so much for the Amazon shopping list. The 6 gauge wires are expensive!!! for 30amps, do you need 6 gauge? Would 8 gauge wires be enough? Are you getting this solar/mppt from Renogy? DCC30S 12V 30A Dual Input DC-DC On-Board Battery Charger with MPPT I'm also getting t his Renogy flexible solar panel. 175 Watt 12 Volt Flexible Monocrystalline Solar Panel Do you have any heat concern with wire run underneath the car?

I'm looking forward to see more of your installation photos once it's done. Thanks so much.

 

[critical367]

Yes, I have the DCC30S. The installation instructions (you can download from the site before purchase) specify the wire gauge based on distance, and that is based on voltage drop rather than amperage. The wire was definitely the single most costly item after the controller! 25' would have been just enough to do the car and trailer but I left more extra than necessary when I cut it at the bumper. It is far enough from the exhaust that heat should not be a problem. Someone else on the forum (and this thread) also ran it underneath.

I plan to get the 200W Eclipse suitcase without controller.

 

[daihung]

Would something like this work? https://www.amazon.com/TOPDC-Jumper-Cables-1-Gauge-Booster/dp/B073VHMYGR/ref=sr_1_2_sspa?crid=3OUTNWBJVHDVK&keywords=6+gauge+jumper+cable&qid=1646672485&sprefix=6+gauge+jumper+cable,aps,68&sr=8-2-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUExODlITDdCMjRVNkI2JmVuY3J5cHRlZElkPUEwMDcyNTcyMlQxSUNRM1FXM0QzSiZlbmNyeXB0ZWRBZElkPUEwODU4NjI0VFdFQ1gzT09TNkEmd2lkZ2V0TmFtZT1zcF9hdGYmYWN0aW9uPWNsaWNrUmVkaXJlY3QmZG9Ob3RMb2dDbGljaz10cnVl Cut the clamp and just use the cable. Not sure of the quality thought.

Maybe this as well. https://www.amazon.com/TOPDC-Jumper...lja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ&th=1 These are 1 gauge. Just need to find the 6 gauge one that are long enough. Cut the clamps and just use the cable.

Amazon.com: TOPDC Jumper Cables for Car Battery 16 Feet 6 Gauge -40℉ to 167℉ Heavy Duty Booster Cable with Carry Bag (6AWG x 16Ft) : Automotive

Buy TOPDC Jumper Cables for Car Battery 16 Feet 6 Gauge -40℉ to 167℉ Heavy Duty Booster Cable with Carry Bag (6AWG x 16Ft): Battery Jumper Cables - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

 

[critical367]

Those are copper clad aluminum with plastic covering. My understanding is that aluminum is not ideal and those cables may not be as flexible. This is not my area of expertise so maybe someone else has an informed opinion.

 

[Jim_in_PA]

The price of copper is extremely high right now so larger feeder cable, even in the building trades, is typically done with Aluminum. The downside is they are thicker and yes, harder to bend. I suspect that the copper clad material is a compromise because of that.

 

[critical367]

Car part of the DC-DC charging circuit is done . I was too slick with the holes and forgot to allow for the heat shrink, so then I had to cut a notch. The Anderson is bolted on with stainless #8 and nyloc nuts. That part of the bumper is quite bendy, which was helpful as the 7-way plug is in the way of drilling and screwing. I sealed the end of the Anderson with silicone. Photo to show that the bumper cover still fits .

Other photos show chassis ground point for the negative, Renogy fuse block held to battery bracket by 3M VHB tape (I had some that came with GoPro mounts and will make a better bracket but it seems secure. As mentioned previously, the wires dive down from the battery and immediately up behind shields until they exit at rear wheel. After finishing at the bumper, I ziptied the wires to a bracket with a bit of slack then pulled the rest of the slack to the engine compartment.

My other boo-boo was not reading reviews carefully on Amazon as the crimper I bought was not very good. But I measured 14.6V at the Anderson pins and nothing exploded .

Car needs a wash, but hard to keep it clean during a BC winter and I had to get this done before we start heading east in 1 month. Hope this helps others as I got lots of insights from reading this forum.

 

[daihung]

Critical367, thank you for all the photos. I'm sure I'll have lots of question when the time comes for me to do it myself. I'm exiting to hear how your trailer part installation goes. Thanks for sharing the knowledge.

 

[critical367]

Critical367, thank you for all the photos. I'm sure I'll have lots of question when the time comes for me to do it myself. I'm exiting to hear how your trailer part installation goes. Thanks for sharing the knowledge.

Trailer side done now. The Anderson plugs are really solid. As mentioned above, I sealed the back end with silicone. I switched over to a hydraulic crimper, made in the USA, but the dies still seem to be metric although labelled with AWG as well. The only "perfect" crimp (to my non-professional eye) was with the Anderson lugs. So possibly the lugs from Amazon for the other terminals are thinner walls and I had to go down one size with the crimper.

For the Renogy DC-DC/MPPT combo, I took the black 12V charging line from the 7-way off the positive bus and connected it to the Renogy IGN+ line (small red wire). The rest is specific to my Airstream Caravel 16RB; I tidied up the original rats nest, got rid of an oversized junction box, and added 2 12V accessory outlets as this set up is under the dinette bench seat. When I fired it all up, I was showing about 26-27A flowing to the 2 100Ah lithium batteries. Let me know if you have any questions!

 

[daihung]

Hi Critical367,

Do you know if the Ascent use a regular alternator or a smart alternator? If later, how do you wire that to your trailer to the car? If the Ascent have regular alternator, I guess you don't need to use the IGN port is that right? Thanks.

BTW, great work wiring everything. I'm starting to order parts hopefully I can start the same project soon.

 

[critical367]

Hi Critical367,

Do you know if the Ascent use a regular alternator or a smart alternator? If later, how do you wire that to your trailer to the car? If the Ascent have regular alternator, I guess you don't need to use the IGN port is that right? Thanks.

BTW, great work wiring everything. I'm starting to order parts hopefully I can start the same project soon.

It is a smart alternator from what I could find. The black wire from the 7-way connector (pin 4) is auxiliary power. In my Airstream, the trailer side wire was connected to the positive bus and provided a measly 4-5A for charging. It is only live when the ignition is on, so it serves perfectly for the Renogy IGN connection. I removed it from the bus and spliced it to the IGN wire that comes with the Renogy.

 

[critical367]

It is a smart alternator from what I could find. The black wire from the 7-way connector (pin 4) is auxiliary power. In my Airstream, the trailer side wire was connected to the positive bus and provided a measly 4-5A for charging. It is only live when the ignition is on, so it serves perfectly for the Renogy IGN connection. I removed it from the bus and spliced it to the IGN wire that comes with the Renogy.

Followup - the black wire in the connector is not keyed to the ignition as I thought but always live. For my travel trailer, I just have to remember to disconnect when parked for the night.

 

[daihung]

Followup - the black wire in the connector is not keyed to the ignition as I thought but always live. For my travel trailer, I just have to remember to disconnect when parked for the night.

I ended up not tapping any wires for the ignition 12v source because I have a bluetooth volt meter installed on the battery and for an hour of driving, the voltage remained at 14.3v. I don't think my 2020 Ascent has a smart alternator.

 

[critical367]

I ended up not tapping any wires for the ignition 12v source because I have a bluetooth volt meter installed on the battery and for an hour of driving, the voltage remained at 14.3v. I don't think my 2020 Ascent has a smart alternator.

I noted the same with voltmeter while running the engine in driveway for maybe 15 minutes. But the sensor on the battery negative terminal is supposedly another sign for presence of a smart alternator. Definitely not my area, and I thought someone would know. I do not think there is any downside to having ignition wire connected to the Renogy unit.