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Old 04-20-2021, 09:22 PM   #21
carlrx7
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Quote:
Originally Posted by hemiallen View Post
That's a new one , so the trucks batteries will run the inverter, you'll feed power while driving through the Gen prep's box and use the RV converter to charge your batteries. Seems less potential to cause harm to the truck's recharge system.
Is this the inverter you purchased
https://www.aliexpress.com/item/4000...8%2315607%2378

Will what you purchased max the converter-charger's charging rate?

Hope it works good for you, changing to 120v seems like a good option.

Allen
It should, assuming its max is 50A using the boost wizard button.

Here is the inverter I ordered.

https://www.aliexpress.com/item/2054...257f4c4dYgQGjM

I liked the remote switch and the battery terminals seem more secure... Also had some favorable brand reviews on youtube.
 
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Old 04-20-2021, 10:24 PM   #22
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Thank you

Allen
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Old 09-23-2021, 08:58 AM   #23
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Did you just tighten the screws back up against your J channel conduit? Are you concerned it will get wet inside while driving in wet weather?

I'm in the middle of the same project and stumped at a clean way to bring the wire out "weathertight". I have my fiberglass fish rod already thru the gap to the battery locker.
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Old 05-07-2023, 10:09 PM   #24
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I would love to hear more on how this is working for you and see some pictures.
Appreciate your help.
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Old 05-08-2023, 06:12 AM   #25
Lee-CI
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The link below from Daryles is one of the best I've read and the one I used for my installation. Worked flawlessly.
https://www.montanaowners.com/forums...hlight=charger
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Old 05-08-2023, 08:21 AM   #26
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Quote:
Originally Posted by Majorpolk View Post
I would love to hear more on how this is working for you and see some pictures.
Appreciate your help.

First, just to address the question regarding waterproofing at the pin box. I used Gorilla tape to seal around the vinyl and pin box. Use alcohol to clean the surface first for best adhesion results.


Well, last March 2022 we were once again on Ocracoke Island OBX NC. I did not bring the generator because this was the only place we're were going that year that we wouldn't be on shore power. We spent 10 days there. It was a cold spring. We started with 1 & 1/2 tanks of propane. We ran out the last 3 days. There is no refill stations on the island. We had to buy a 20lb BBQ tank to get us by the last 3 days. The solar system worked perfectly.
FYI regarding the suggestions for putting the panels in series versus parallel. I experimented with both connections. I found putting them in series (higher voltage) got better results for me. Last month (2023) I added two more 200W panels (800w total) in parallel to the existing 200W panels. So now I have 2S2P configuration. I do need to upgrade the MPPT. I'll probably go 150/75 for future expansion. I tweaked the MPPT absorption and float settings to optimize output, however the last three days we were there it was cloudy and rained. No solar.
I connected the DC-DC charger, started the truck and ran it twice a day for an hour to charge the batteries. It was cold enough outside not to worry about the alternator overheating so I didn't have to put a fan blowing on it. I did open the hood for extra air circulation.
BTW, when the truck is NOT hitched you need to run a battery jumper cable from the trailer frame to the truck frame for the Renogy DC-DC charger to turn on. I'm guessing they need to be on the same ground plane to operate (circuit loop).
Something else I have also found out since I wrote this, for the 2016 F350 super duty with dual 200a alternators, only ONE alternator actually works until it reaches 80% before the other one starts picking up the load. Yours may be different.
This year we are heading west. We had to cut the first month off our trip (NM, UT Moab). We are still planning on Tetons, Yellowstone, Glacier then on up into Canada to Banff and Jasper. We will be there for about two months (NO hook ups, dry camping the entire time). This time we brought two Harbor Freight 2000W generators and a 30A parallel kit. In most Canadian Provincial and NP they have VERY limited generator hours, so the solar and DC-DC charger will be a good backup.

First picture, wiring from pin box.
Second picture, battery compartment wall. The DC-DC charger is not in the picture. It's on the wall to the left of the inverter.
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Old 10-07-2023, 11:34 AM   #27
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Daryles, sorry to post in an old thread, but do you have a photo of how you brought the cables through your truck bed sidewall and how you mounted the Anderson connector. I'm getting ready to do this; will be using dual 30A Victron Orion-TR Smart non-isolated chargers.
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Old 10-07-2023, 11:54 AM   #28
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Won't exactly help in your exact situation per se, but should give you general idea
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Old 10-07-2023, 01:24 PM   #29
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Thanks, that helps. Also found this example. Just trying to plan the install.
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Old 10-07-2023, 04:34 PM   #30
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Scott here you go.
I followed existing wire bundles under the truck frame to the back of the bed. There was an existing hole in the left and right side of the bed. I put a PVC valve gromet in the hole to prevent chaffing and ran the cables through.
I just hung the Anderson connector with a Velcro strap.
The cables are long enough to reach the other side in in case you are parallel parked next to the rig. The rig has 8' coiled up in the pin box for the same reason.
First picture is the truck bed right side showing the existing bed hole I used in the left side.
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Old 10-07-2023, 10:53 PM   #31
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Thanks. Is that boot an Anderson product?
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Old 10-08-2023, 06:26 AM   #32
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Yes, the parts list is in the original post at the top.
I got them through Powerwerx
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Old 10-28-2023, 07:23 PM   #33
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I just finished my install. The first test, with my batteries at 80%, provided 32A of charge. That's a lot better than the 4A I was getting with the OEM set up which was not enough to make up for the 12A draw of my refrigerator. It will be interesting to see if it increases when the batteries have less of a charge.
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Old 10-28-2023, 07:25 PM   #34
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Installed dual Victron 30 DC-DC chargers and made a 10' extension cord in case I need to charge off the truck without hooking up. I pulled the cables to the battery compartment on the same path as the existing cables from the pin box.
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Old 10-29-2023, 08:13 AM   #35
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Nice job!!
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Old 10-29-2023, 09:02 AM   #36
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Nice! I know very little about this subject but want to improve my overnighting off grid while traveling. Just yesterday received a Victron 712 shunt to install so I can get a handle on what’s going on. I’m thinking a couple hundred amps of lithium and a dc-dc charger may be all I need for what I want to do. I’ll probably have questions when the time comes.
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Old 10-29-2023, 04:01 PM   #37
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My Ram 3500 only has a single alternator so I am using a Victron 30 amp dc to dc converter. In the truck I installed a contractor and circuit breaker that I can turn on the dc to dc converter with one of the dash mounted switches. This last summer I typically waited until we were on our way before turning it on giving the truck a chance to recharge the battery from starting reducing the load on the single alternator. It has worked really well. In the truck bed I have a dealer anderson plug (120amp) for quick plugging in. I went with that large of a connector due to voltage drop from the front of the truck all the way to the garage where the dc to dc converter is. One of the wire sized calculators I used stated for 12vdc, running 25’ and 30 amps you need #1 wire due voltage drop.
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Old 10-29-2023, 07:29 PM   #38
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Quote:
Originally Posted by Greg10yes View Post
I typically waited until we were on our way before turning it on giving the truck a chance to recharge the battery from starting reducing the load on the single alternator.
Your Victron DC-DC charger has a "delayed start" setting to allow the truck battery to recharge before starting to charge the RV batteries. Default is 2 minutes.

From the manual:

"Delayed start voltage delay (tstart delay): Recharge time for the starter battery during start level (delayed). Example: If the starter
draws 150A for 5sec to start the engine, about ~0.2Ah is drawn from the starter battery. If, during engine idling, the alternator can
only generate 20A, it takes 150A/20A x 5sec =37.5sec to recharge the starter battery. Default: 2 minutes."
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Old 01-24-2024, 02:46 PM   #39
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Originally Posted by Daryles View Post
I just finished installing a Renogy 60A DC-DC charger in my 5th wheel.
The purpose of this is to be able to charge your RV batteries from your truck "safely" whether parked or driving. The 7 way cable from the truck to the RV does provide some charging. The most I have measured is about 7A. It would take all day and then some to recharge your batteries if they were low.
This gives you alternatives if you dont want to haul a generator on a short boondocking trip BUT you want backups to your solar power system (400W and expanding) if you have cloudy days.
By "safely" charging, I mean without draining the truck batteries to where you cannot start the truck AND where you dont fry your alternators. I have lithium batteries and when drained they can pull 100A charging.
Look up the YouTube video on burning out an alternator when charging a lithium battery.
In an emergency you CAN just use jumper cables from the truck to the RV to recharge them. Just ask the people in Texas who went through that record breaking deep freeze without shore power or a generator. They used their trucks and jumper cables to keep their RV batteries charged so they could run their furnaces.
Anyway the details...
I have an F350 Super Duty with dual 200A alternators and dual batteries. So the truck is more than capable of handling the load.
In the RV, 552Ah of lithium batteries and 400W of solar panels and a Victron 100/30 Smart Solar MPPT. I also kept the original 100Ah FLA battery as a backup. I have a 250A three way switch to control what is connected.

FYI, DC-DC chargers can come in two forms.
Isolated: you run + & - cables from the source battery to the charger then run + & - cables from the charger to the RV battery.
This installation I believe is best if you have separate source and RV vehicles.
Non-isolated: you run a + cable from the source battery to the charger then a + cable from the charger to the RV battery. A single - cable goes from the charger to the chassis. This installation I believe is best suited for a boat, class A, B, or C RV where all components share the same chassis.

The Renogy charger I chose is an Isolated version. Running copper wire has less losses than using the chassis. The steel frame is 33% less conductive than copper.

RV work.
I loosened the vinyl cover under the overhang covering the pin box by removing the 4 screws next to the pin box. I put the vinyl siding "J" channel face to face to make a conduit. Then I pushed the 4 gauge wire through the J channel. I did this so if I needed to add any future wiring I already had a conduit from the pin box to the battery compartment. I pushed a yard stick carefully between the vinyl and the insulation then turn it vertical to open a gap. I sharpened one end of the J channel and carefully pushed it through the gap between the vinyl and the insulation to the battery compartment.
I made these cables (+ and -) long enough (8' pin box to Anderson plug end, 17' total) to be able to reach the truck plug in from either side if the truck was parallel parked beside the RV.
I mounted the charger and 70A circuit breaker. All my equipment is mounted labeling upside down. This is due to the cooling fans of the equipment. I did not want them blowing hot air into each other. In this position the hot air is blowing away from each other. Other considerations was the position of the inverter 120vac outlets.

Truck work.
Routed the cables, installed the 90A circuit breaker. Put anti chaff cable wrap where necessary and secured all the cabling tight.
In the truck bed I used a PVC valve gromet in the truck bed sidewall hole as a gromet to prevent wire chaffing. Pay close attention to what goes on first when assembling the Anderson connectors. Slide weather boot onto cables, crimp on connector contacts, insert contacts into Anderson connectors.
I am fortunate the guys at my local auto parts store have giant cable crimpers (like bolt cutters). Once I had the cables pulled through the truck and secured and the RV cables cut to the lenght I wanted, I removed the cables from the RV and I drove to the auto parts store with all the cables. Once there the guys crimped all the connectors on the ends of the cables in the truck and for the RV cables. I had to grind down the sides of the Anderson contacts because when they crimped them onto the 4 gauge cable it flattened them a bit so they were too fat to go into the connectors easily. After grinding them down a tiny bit they fit comfortablely.
Took everything home and put the RV cables through the J channel conduit, assembled the Anderson connectors and connected the other end to the charger.
The charger requires a 12vdc on signal. I just put a wire with a switch from the charger to the 12vdc buss bar.
Testing...
Connected the truck to the RV via the Anderson connectors, started the truck, closed the circuit breakers in the truck and RV. Turned on the switch and "voila"!!
Green light on the charger.
I had already ran down my batteries to 40% (13vdc in my case). My Victron BMV-712 battery monitor measured 54A input current into my batteries. I think that’s pretty good for a 60A DC-DC charger. The battery state of charge (SOC) was up to 45% in 15 minutes. Truck was at idle speed.

When we left the house a few days later on our latest road trip, the RV batteries were at 39%. I decided to see how much they would charge with the tow cable + 400W solar panels. After 5 hours of travel time batteries were at 43%. Cloudy day. We had 1 hour to go before our overnight stop. I plugged in the Anderson connectors and turned on the DC-DC charger. It read 57A charging on my BMV. When we reached our overnight stop an hour later the batteries were 100%. Im really happy with that. The real test will be in a few days. We will be in the OBX boondocking for 5 days. No generator. Just solar and the DC-DC charger.

Parts
Renogy 60A DC to DC charger
Anderson 175A connectors
Anderson
SB175 Environmental Boot with Cover, Source Side
SB175 Environmental Boot with Cover, Load Side
(Anderson products from Powerwerx)
90' 4 gauge copper welders cable (flexible)
4 gauge copper lugs
Buss 90A circuit breaker
Buss 70A circuit breaker
12vdc switch, lighted
Scrap vinyl siding "J" channel

DC-DC charger, Isolated vs Non-isolated operation
https://alenconsystems.com/learning/...cdc-converter/

Another aspect of this is being able to run one air conditioning (A/C) unit while driving.
You install a SoftStartRv (Mike Sokol has talked about this)
https://www.rvtravel.com/rv-electric...-hrdl-testing/
If you don't already have a transfer switch installed, wire one A/C unit to a transfer switch where you can run it from your inverter while driving. Your DC-DC charger will keep the batteries topped off while driving. You arrive at your destination with the RV already cooled down.
won't the amp gauge in the vehicleshow high amps when charging
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Old 01-24-2024, 03:08 PM   #40
Daryles
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won't the amp gauge in the vehicleshow high amps when charging
To be honest I never noticed.
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