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Cargo Trailer Conversion - Electrical Build out (And any other suggestions)

bedpan

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I have had a couple of travel trailers over the last few years. The family and I have put somewhere around 30,000Mi on. I have had some major frame issues with my last one so I sold it and plan to build my own. I just ordered an 18' all aluminum trailer that comes in about 6 weeks or so. Initially its just going to be a tent and kitchen on wheels. As time allows I will build it out.

Electrically just like the trailer will be a work in progress. Just enough to get by until I can get by with buying some more.
I have access to a few Renogy 100AH batteries that I can use for trips for the next while.
I also have a 1000W inverter that I used last year to run a small fridge.

For our first trip I would like to get the inverter installed in the trailer with 2x100AH Renogy batteries... Further I was planning on ordering a 50A DC2DC Renogy charger. To facilitate charging for this first trip I figured I would just wire up the DC2DC charger and run/idle my truck to charge up the batteries every couple of days.

I have a chicken scratch wire diagram on my desk here...
PXL_20220525_003325023_2.jpg

To walk through it.. Left side is the truck. Off the battery a 75A fuse (as per renogy manual for the 50A charger). aprox. 20' of 4 AWG cable to the bumper. Anderson connector at the bumper.
Into the trailer is an Anderson Connector to the truck. The plan was for the Electrical gear to be at the rear of the trailer. So banking on another 20' of 4 AWG to the DC2DC Charger. Out of the DC Charger into a 65A fuse (again as per Renogy guide)

Now for the first trip drifting away from my diagram, we will skip the terminal blocks. Diagram shows a 2000W inverter.. I actually only have a 1000W for now

Off the house batteries I will start with a 100A fuse running on 2 AWG (overkill for now but if I upgrade the inverter likely needed). THis connects to the 65A fuse from the DC2DC Charger and to the Inverter.

DC Load wise for now will be nothing but an water pump and maybe a couple 12V fans we have and maybe a USB charger.
AC Load will be my small fridge. Last summer a full 100AH battery would run the fridge for about 60 hours. (Fridge draws around 1.7AH).

Sooooo here comes the question part.

  1. The truck is a 19 F150 with a 5L in it. The alternator is 240A. I think (read hope) that should be good to idle and charge at 50A's. Any concerns running at full hit 50A while idling?
  2. Further to this I have read the new Renogy DC2DC chargers can be throttled. Anyone know how to do this? I see nothing in the manual about it but I guess its an app setting via bluetooth? (https://renogy.com/blog/so-many-dc-...little-timewhich-one-is-best-for-your-system/)
  3. Cable sizes.. Thoughts? Will 4AWG be large enough for this long of a run? If we relocate the electrical to the front we could probable get down to 25' (one way).
  4. Cable Sizes.. Will the 2AWG be large enough for a 2000W inverter. Cable run from the battery to the inverter would likely be less then 2' (one way)
  5. Fuse sizes.. Thoughts..
  6. Fuse types... What fuse types/breakers would you guys recommend? Trying to keep prices reasonable but I also don't want to waste money and have to replace a bunch of times.

Well.. thats a lot. Thanks kindly for taking the time to read!

Mike
 
I'll answer what I can.

3. Cable sizes.. Thoughts? Will 4AWG be large enough for this long of a run? If we relocate the electrical to the front we could probable get down to 25' (one way).
You have 12V 50A with an 80' roundtrip between the alternator and the DC2DC converter. Using 4AWG wire will result in a 10% voltage drop. To keep it down to 3% you need 2/0AWG. If you can get it down to 50' roundtrip then 1AWG would work for keeping the voltage drop at 3%. If you can accept 10% then 6AWG will work for 50'.

4. Cable Sizes.. Will the 2AWG be large enough for a 2000W inverter. Cable run from the battery to the inverter would likely be less then 2' (one way)
A 12V 2000W inverter can pull up to 200A from the battery. You want at least 2/0AWG (much larger than 2AWG) to the inverter.

You also show DC loads. How many amps will that need to handle? The wires from the batteries to the bus bars needs to handle the 200A inverter load plus the max DC loads. This likely means you need 4/0AWG wires between the batteries and bus bars.

For the 50A DC2DC converter, the wires from the converter to the bus bars can be 6AWG if those wires are short. 4AWG works fine too. It's the long run from the alternator to the converter that needs to be larger due to the length.

5. Fuse sizes.. Thoughts..
With a 2000W inverter pulling 200A you would want a 250A main battery fuse assuming you went with 2/0AWG (or bigger). You can get by with a 125A fuse with the 1000W inverter.

But that doesn't take into account the DC loads. So take the 200A inverter loads plus the max DC loads. That gives the total amps the battery may have to provide. Multiply that by 125% to get the main battery fuse size.

You will want a fuse for the DC fuse box. That depends on the chosen wire size which depends on the max DC loads you need to support.

Do make sure that your bus bars are rated higher than the largest fuse you end up using in your system. You do not want the bus bars to be the weak point in the wiring.

Once you have the 2000W inverter and a 200A load possible from the batteries then no one battery can handle those loads. Assuming your 100Ah batteries can provide 100A of discharge current then you need at least 2 in parallel to run the inverter at full power. Since each battery can provide that full amount you should also fuse each parallel battery with a 125A fuse. This is in addition to the 250A (or higher once you adjust for the DC loads) main battery fuse.

6. Fuse types... What fuse types/breakers would you guys recommend?
The main battery fuse should be a Class T fuse for LiFePO₄ batteries. If your batteries a lead based then ANL would be fine.

The inverter fuse should be a MEGA fuse. A MAXI fuse might be a good choice for the DC fuse block.

I have no experience with alternator charging and DC2DC converters so I can't help with those.
 
Thanks for the reply!

You have 12V 50A with an 80' roundtrip between the alternator and the DC2DC converter. Using 4AWG wire will result in a 10% voltage drop. To keep it down to 3% you need 2/0AWG. If you can get it down to 50' roundtrip then 1AWG would work for keeping the voltage drop at 3%. If you can accept 10% then 6AWG will work for 50'.
I went with 4AWG as that's what the Renogy manual specifies for longer runs. Anyone know what the Renogy DC2DC Charger can accept for input to be successful charging? I suspect it would be fairly wide input range it can accept? The Battery Range in the manual says 9-16V......


A 12V 2000W inverter can pull up to 200A from the battery. You want at least 2/0AWG (much larger than 2AWG) to the inverter.
What wire size calculator do you recommend? I have different results but not sure which one I used. Is there a standard one most forum members use?

You also show DC loads. How many amps will that need to handle? The wires from the batteries to the bus bars needs to handle the 200A inverter load plus the max DC loads. This likely means you need 4/0AWG wires between the batteries and bus bars.
The DC loads will be minimal for now but could grow as time goes one. Right now it will be a small on demand water pump, some small fans, usb charger and some lights. All in maybe 30A on the very high side. This could grow if I swap out the fridge for a DC fridge at some point.

For the 50A DC2DC converter, the wires from the converter to the bus bars can be 6AWG if those wires are short. 4AWG works fine too. It's the long run from the alternator to the converter that needs to be larger due to the length.


With a 2000W inverter pulling 200A you would want a 250A main battery fuse assuming you went with 2/0AWG (or bigger). You can get by with a 125A fuse with the 1000W inverter.

But that doesn't take into account the DC loads. So take the 200A inverter loads plus the max DC loads. That gives the total amps the battery may have to provide. Multiply that by 125% to get the main battery fuse size.

You will want a fuse for the DC fuse box. That depends on the chosen wire size which depends on the max DC loads you need to support.

Do make sure that your bus bars are rated higher than the largest fuse you end up using in your system. You do not want the bus bars to be the weak point in the wiring.

Once you have the 2000W inverter and a 200A load possible from the batteries then no one battery can handle those loads. Assuming your 100Ah batteries can provide 100A of discharge current then you need at least 2 in parallel to run the inverter at full power. Since each battery can provide that full amount you should also fuse each parallel battery with a 125A fuse. This is in addition to the 250A (or higher once you adjust for the DC loads) main battery fuse.


The main battery fuse should be a Class T fuse for LiFePO₄ batteries. If your batteries a lead based then ANL would be fine.
Can you link to a Class T fuse you would recommend?


The inverter fuse should be a MEGA fuse. A MAXI fuse might be a good choice for the DC fuse block.
The Mega and Maxi fuses; are they Victron? I ones link to by Will are USA based only. I am trying to find a comparable I can get in Canada.

I have no experience with alternator charging and DC2DC converters so I can't help with those.

Much thanks again!
 
What wire size calculator do you recommend?
The ones from Blue Sea Systems is really good. You want one that takes into account ampacity and voltage drop, among other factors. They have a chart you can download as well as a phone app and online calculator.

The online calculator can be found at the following (which also has links to the phone apps):


The chart can be found at (scroll down and look for the wire size chart):


The DC loads will be minimal for now but could grow as time goes one. Right now it will be a small on demand water pump, some small fans, usb charger and some lights. All in maybe 30A on the very high side.
So plan on 200A from the inverter and 40A from the DC loads. 240A requires 4/0AWG (3/0AWG but that's hard to find). With the batteries wired with 4/0 for 240A you would want a 300A main battery fuse and 400A bus bars.

Can you link to a Class T fuse you would recommend?
Not sure you can get this in Canada but try Don Rowe:


The nice things about that place is you can get the fuse and a holder as a kit so you know you are getting the correct size holder for the fuse. Class T fuses are different sizes depending on the amperage.

If that site doesn't work for you, Blue Sea Systems sells Class T fuses and holders that you might be able to get on Amazon. They are not cheap. Just be sure to get the correct sized holder for the fuse.

The Mega and Maxi fuses; are they Victron?
No, they are generic fuses sold by lots of places. I got Blue Sea Systems versions on Amazon.
 
went with 4AWG as that's what the Renogy manual specifies for longer runs.
4AWG wire will result in a 10% voltage drop. To keep it down to 3% you need 2/0AWG.
I’d decide roughly how much solar charging you will likely eventually use, and select readily available panels (so they can be matched when added to later) to create a minimal ’starter’ solar array and SCC.
I am 24/7/365 on currently 800W and can use 1000W, 1200W, or 2000W pure sine inverters that I have on hand. Currently using this unit successfully but I am growing to prefer separate components. Which is why I say this:

Three 200- 250W panels will probably keep you charged minimally but effectively day to day with an Epever or Victron SCC.
The cost of DC2DC charger plus adequate cabling is how many $$$? This if not spent will offset quite a bit of a few panels and an Epever, leave opportunity for growth, and be autonomous without running the gasoline truck.

That’s what I would do.
 
I’d decide roughly how much solar charging you will likely eventually use, and select readily available panels (so they can be matched when added to later) to create a minimal ’starter’ solar array and SCC.
I am 24/7/365 on currently 800W and can use 1000W, 1200W, or 2000W pure sine inverters that I have on hand. Currently using this unit successfully but I am growing to prefer separate components. Which is why I say this:

Three 200- 250W panels will probably keep you charged minimally but effectively day to day with an Epever or Victron SCC.
The cost of DC2DC charger plus adequate cabling is how many $$$? This if not spent will offset quite a bit of a few panels and an Epever, leave opportunity for growth, and be autonomous without running the gasoline truck.

That’s what I would do.


Thanks for the suggestion. I had to ponder things for a few minutes and look at our usage. The reason I gravitated to DC2DC charger is that we tend to drive a fair bit. And if we are not driving we are usually in the woods...

I do plan on adding solar and long term I would love to get enough on top of the trailer to run the whole thing and maybe even run an AC unit for a couple hours at night. The DC2DC is just a sure thing though and insures for this year anyways that we always have juice.

I agree on the separate components. It makes troubleshooting and fixing things on the fly much easier. I did order the Renogy 50A DC2DC charger with MPPT. I figure I can start with it and its limitation but add a better MPPT charger once I have enough panels to justify it.

We only camp in the trailer 5 or 6 weeks a year right now. So this is a part time project with a part time budget. Its going to take me a few years to get to my final build.

Much thanks for the idea!
 
agree on the separate components. It makes troubleshooting and fixing things on the fly much easier.
Well, yes. However my seat-of-the-pants having played around with various things the last couple of years is that I get less ‘idle’ consumption out of components than the AIO unit. At first I was going with the idea my batteries are aging (lead acid) but the batteries seem to be as expected from past experience on sunny days. Cloudy days, though, and the idle draw- though small in relative terms- seems to take a toll.
Separate components didn’t affect me on cloudy days as much in my subjective observations.
 
Well, yes. However my seat-of-the-pants having played around with various things the last couple of years is that I get less ‘idle’ consumption out of components than the AIO unit. At first I was going with the idea my batteries are aging (lead acid) but the batteries seem to be as expected from past experience on sunny days. Cloudy days, though, and the idle draw- though small in relative terms- seems to take a toll.
Separate components didn’t affect me on cloudy days as much in my subjective observations.
Interesting observation.

I will be going Lithium from the get go. Borrowing to start and then buying when a deal comes up.

As I said we tend to drive a lot and have road trip. We have been coast to coast in Canada. Newfoundland to BC. Done several trips to the Gulf Coast. In Covid years we spent a lot of time on Crown land in Northern Ontario driving from site to site and fishing in between. We don't tend to spend more then a couple days at any single site. I am hoping the DC2DC will keep us mostly topped up. Idling my Truck for an hour is about .5 Gallons (based on a quick search). So although not cheap right now its an easy top up!.
 
Welp...

I got the Renogy DC-DC charger out of the box.. It seems to be working fine. For testing purposes I have it on the bench. 20' leads out to my F150 Battery. Then onwards to my Battery bank, 2xRenogy 100AH 12V. It works good. No ignition wire hooked up but its doing what its suppose to and cranking 50A out of the truck into my bank when I start it.

I also bought one of the renogy 20A AC-DC chargers. It worked for one battery. The second one it said no to.. Now it does not work at all. Green light turns on but no charge at all for the batteries. Tried on 3 separate batteries.

Renogy (Canada) has not responded to the cases, or emails I have sent them. Its been 3 days now with zero response out of them. I tried the USA support number today. 3 times on hold for 10-12 minutes and the line goes to dead air..

Maybe there is a reason for the hate on Renogy.. ugh...
 
Well been working away on the system.. I have just built it right now on some 3/4" ply. When the trailer shows up in a week or two we will be camping in it pretty much right away. The first few trips its going to be a tent on wheels. Then we will start building it out as time allows.

Here is how she looks so far.
PXL_20220627_002207567.jpg

Borrowing the three Renogy batteries for now and 4x100W solar panels..I will likely lay this down on its side and attach it to the trailer wall. The large cord up in the top right goes to an Andersen connector on the bumper of the truck..

This cable is undersized for right now.. I will monitor thought and see how it goes. It does deliver 50A thought. You can drop the charge rate so I may pull it down to 20-30A. We will see.

I need to add some sort of kill switch on lines for the DC2DC charger and the AC Chargers to the bus bar. I noticed I killed the battery main and the inverter was still running as I had the AC Chargers plugged in.

Thoughts and suggestions?
 
Is that a pure sine inverter?
Nope...

But its what I got. Only used to run a fridge right now that has been running on it for 5 weeks or so problem free... Hopefully temporary for a few trips this year until I go to a 2k or 3k inverter.

I did buy a cheap Canadian Tire 1500W inverter that was pure sine wave but it was drawing a constant 6W compared to this one at about 2W... So I returned it.. Just seems like a lot of power to give up with my limited generation options.
 
Only used to run a fridge right now that has been running on it for 5 weeks or so problem free..
I’ve killed way more dollars in a short time on modsine than my first pure sine cost and I knew better. Just can’t do that.
Somewhere I still have a 400W modsine that killed a brand computer monitor in 45 mins. I wish I knew where it was- I want the cord off of it :)
 
I’ve killed way more dollars in a short time on modsine than my first pure sine cost and I knew better. Just can’t do that.
Somewhere I still have a 400W modsine that killed a brand computer monitor in 45 mins. I wish I knew where it was- I want the cord off of it :)
Right now its just running a $100 walmart bar fridge... As I read more about it I did not realize how shitty they can be.. So thats all that will be plugged in for now.

Watching the used ads for something better but the dollars are tight right now.
 
Watching the used ads for something better but the dollars are tight right now.
Sell it as soon as you can, then.

I used a 1200W Giandel pure sine near four years reliably and for over a year of that it was on 24/7 for my fridge. Probably still only about $200 but I see them marked down to $150 on amazonian occasionally
 
Sell it as soon as you can, then.

I used a 1200W Giandel pure sine near four years reliably and for over a year of that it was on 24/7 for my fridge. Probably still only about $200 but I see them marked down to $150 on amazonian occasionally
I appreciate the advise. I will do just that!

I struggle a little bit.. Ideally I would like to go 24V... But then I have to change everything. If I buy an Inverter as a interim option its kinda wasted as it will be until I do bigger better things.. Maybe I will find another cheap one from Canadian Tire..
 
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