DC-DC Charger Install

[MAX Burner]

After detailed discussions with @Geronimo John regarding a DC-DC Charger installation, we finally got around to making it happen.  There's a ton of posts on this mod/upgrade, so we're not going down the rabbit hole to the end - just saying that it's a worth while mod to consider.  Essentially, our concern was the 12AWG DC circuit from the 7-pin connector supplying an inadequate DC current to the OTT while towing, especially during the hours of darkness when there's no solar input to the battery bank.

So, we decided to go with the Victron 12/12 30amp Bluetooth unit to be compatible with our other Victron devices (Smart Shunt, MPPT Solar charger, and the Cerbo S-GX multiplexer).  We decided to upgrade from the OTT factory PWM solar module controller to the Victron MPPT unit.  We also added the 7" Victron Touch to monitor all our AC and DC input/output activity which has been a game changer for us.  Here's a series of pix that may satisfy the curiosity of those interested in efficiently charging the battery bank.

FYI:  We've got 3x BB's and ran 1/0 cables from the TV's smart alternator to an Anderson plug installed at the hitch, then 4 AWG cables from the Anderson through a Blue Sea Cable Clam to the Victron DC-DC charger installed under the aft dinette seat.  The cables were snaked from the forward bulkhead under the toilet to the forward dinette seat, under the dinette table, to the aft dinette seat area:

Below shows the location for the Victron Cerbo S-GX Touch Screen...

This is the location where we mounted the new Victron MPPT Smart Solar Charger, upper street side compartment where the old PWM solar charge controller was mounted:

We mounted the Victron remote solar controller monitor to the right of the Touch Screen...

Building the Anderson plug for the OTT with 4AWG cables...

Below shows the Blue Seas Cable Clam hull penetration adjacent to the 7-pin cable...

Victron DC-DC Charger mounted on the street side wheel well/aft dinette seat next to the Progressive surge protector...  Note the 50amp breaker between DC-DC Charger and the battery bank.  We installed another 50amp breaker between the TV alternator and the Anderson connection:

Pulling 4AWG cables from the hull penetration under the head sink thru the front of the toilet and to the aft dinette seat area...

Thanks to @ScubaRx - Steve gave a great suggestion for snaking wires through challenging areas using a stiff plastic strap for securing pallet loads...

One and done.  I'm going for a cold one...

Edited November 5, 2023 by MAX Burner
Fixed a typo...

[Rivernerd]

Impressive.  The documentation of your work is clear and easy to follow.  It reminds me of similar posts from John Davies, which is high praise!

[Ronbrink]

19 hours ago, MAX Burner said:

we decided to go with the Vicron 12/24 350amp

What is this referencing?

[Ronbrink]

20 hours ago, MAX Burner said:

We installed another 50amp breaker between the TV alternator and the Anderson connection:

I originally had a breaker at the battery on the cable leading the rear bumper Anderson, but excessive engine heat oftentimes would cause it to overheat and trip. Resorted to an ANL fuse, problem solved. 
 

[MAX Burner]

2 hours ago, Ronbrink said:

excessive engine heat oftentimes would cause it to overheat and trip.

FYI:  We traveled 285 interstate miles yesterday, ambient temps ranged between 50 - 75F, the breaker didn't pop.  We'll need to wait until next spring/summer for the higher temps to see if engine heat will cause it to trip.  For now, we seem to be fine with the breaker as is...

[MAX Burner]

3 hours ago, Ronbrink said:

What is this referencing?

Sorry, this was referencing the Victron DC-DC Charger model...

[Ronbrink]

12 minutes ago, MAX Burner said:

ambient temps ranged between 50 - 75F,

Right, the extreme summer heat here in Texas this summer was a bit too much! Just know the fuse option is a good fix. 

[MAX Burner]

@Ronbrink:  Good call, brother.  The Blue Sea Systems ANL fuse is on our radar screen.  TKX!

[Geronimo John]

8 hours ago, Ronbrink said:

I originally had a breaker at the battery on the cable leading the rear bumper Anderson, but excessive engine heat oftentimes would cause it to overheat and trip. Resorted to an ANL fuse, problem solved. 

 

6 hours ago, MAX Burner said:

FYI:  We traveled 285 interstate miles yesterday, ambient temps ranged between 50 - 75F, the breaker didn't pop.  We'll need to wait until next spring/summer for the higher temps to see if engine heat will cause it to trip.  For now, we seem to be fine with the breaker as is...

This past summer, we traveled in temperatures exceeding 100F.  Our breaker for the 4 AWG DC home run is located just aft of our F-150 engine bay battery.  The breaker and system worked like a champ. 

GJ 

[Ronbrink]

3 hours ago, Geronimo John said:

The breaker and system worked like a champ. 

All or part of the issue I experienced may have also been due to the quality, or lack thereof, of the breaker initially installed. To that point, I had another breaker tripping at the DC-DC after switching from a 20A to 40A charger. Upon research, I learned that this was a common occurrence with use of ‘cheap Chinese’ breakers and the remedy was installation of a ‘quality Blue Sea’ breaker, which resolved that problem. I should mention that with the 20A charger install, I took cable size into account to adequately accommodate any future upgrade in house battery amp hours and thus, a step-up in charger output. 

[Geronimo John]

15 hours ago, Ronbrink said:

we decided to go with the Vicron 12/24 350amp

I am not familiar with your unit.  For our OE trailers, many of use the Victron Orion 12/12 DC to DC units.  And NON of them can handle 350 amps.  

You must have a PeterBuilt to be working cables that size at 12 or even 24 volts.

Just having fun.  But it would be nice if you you would add your TV and Trailer info to your tag line.  See above other posts for good examples.

[Geronimo John]

1 hour ago, Ronbrink said:

I should mention that with the 20A charger install, I took cable size into account to adequately accommodate any future upgrade in house battery amp hours and thus, a step-up in charger output. 

Also interested in what size cables you used and what charger you would use to get beyond the Victron Orion 30 amp units on the market.  

BTW, great fuse unit.

GJ

[Ronbrink]

10 hours ago, Geronimo John said:

I am not familiar with your unit.

Actually, this quote “we decided to go with the Victron 12/24 350 amp” was that of MAX Burner. I too questioned this, he replied it referenced the charger model. This was obviously a typo and edited to 12/12 350 amp, but his pic shows the charger as a 12/12-30. This should ease any concerns of a “PeterBuilt” signature OTT out there! As for the “tag line”, I need to figure out how to add that, but for now: 2012 Chevy 1500 Silverado 4x4; 2020 OLEll, 579, Twin.

[Ronbrink]

10 hours ago, Geronimo John said:

Also interested in what size cables you used and what charger you would use to get beyond the Victron Orion 30 amp units on the market.  

I recently replaced my Renogy 20A DC-DC charger with a Renogy 40A model to accommodate a new 460Ah LFP house battery bank upgrade. With the original install, the recommended 4AWG cable, specified for use of a 40A charger, was used in anticipation of this charger upgrade when a switch to lithiums occurred. 

[MAX Burner]

47 minutes ago, Ronbrink said:

we decided to go with the Victron 12/24 350 amp

...yup, yet another un-caught typo.  Our's is a 30amp DC-DC charger, I'll fix it post haste...  TKX!

[Geronimo John]

5 hours ago, Ronbrink said:

I recently replaced my Renogy 20A DC-DC charger with a Renogy 40A model to accommodate a new 460Ah LFP house battery bank upgrade. With the original install, the recommended 4AWG cable, specified for use of a 40A charger, was used in anticipation of this charger upgrade when a switch to lithiums occurred. 

Impressive!   What is the actual maximum amps are you seeing to the batters with the Renogy 40 amp DC to DC unit?

GJ    

[Ronbrink]

31 minutes ago, Geronimo John said:

Impressive!   What is the actual maximum amps are you seeing to the batters with the Renogy 40 amp DC to DC unit?

GJ    

Here’s a screenshot of the Victron app showing 43.29A with the engine held slightly above idle, with some fluctuation to 40A. At idle the value settled down into a range of 33-36A. The next screenshot was taken 14 minutes later with a 1% increase in charge.

[Geronimo John]

 

Getting the full capacity of the DC - DC charger flowing to the batteries is an indication that you nailed both the installation and set-up.

I'm running #4 AWG copper welding cables full length both ways (To and From the TV and Ollie batteries.  But not getting anywhere near the 30 amp rated output of the Victron Orion to our three 100 AH BB's. Suspecting my settings are the issue.....

 

GJ

[Ronbrink]

1 hour ago, Geronimo John said:

Suspecting my settings are the issue.....

Agree, had to configure the five dip switches to charge lithiums with the Renogys, the Victron may have something similar to set in the Smart app.

[Ty J]

I purchased also the Orion dc to dc charger 30 amp , but I charge from a spare power station I have.

Victron has new DC to DC charger 50 amp that is scheduled to be released in us next month. Its 98 percent efficient compared to existing 82 percent.

Lower temperature from high efficiency. I preordered it, of course they improve it. It also will tie into my victron components .

Great Job on your install.

 

[rideadeuce]

@MAX Burner I just noticed that you installed a non-isolated DC/DC charger. The newly released Orion XS 12/12 50amp charger is only available in non-isolated version and one of the requirements is that the starter battery and house battery share a common earth ground. Did you just run your black negative from the TV battery to the negative bus bar => charger negative to negative bus bar => then from bus bar to ground. I wasn't sure about the wiring. I have the new version that is non-isolated on order and was trying to figure how to wire. 

https://www.victronenergy.com/dc-dc-converters/orion-xs-12-12-50a-dc-dc-battery-charger

Oh, and do you think it is possible to snake the 4 awg cables from the cable gland opening under the toilet to the aft dinette area without removing the bathroom shelf. Is it worth attempting? Or just remove it and proceed. 

 

Edited May 20 by rideadeuce

[rideadeuce]

@Galway Girl Did you swap out your hot bus bar for better or more connections? Could you wire ORION XS Pos output directly to the post where the (2) 4 AWG wires are already connected.

 

[Ronbrink]

16 hours ago, rideadeuce said:

Oh, and do you think it is possible to snake the 4 awg cables from the cable gland opening under the toilet to the aft dinette area without removing the bathroom shelf. Is it worth attempting? Or just remove it and proceed. 

I have successfully fished wires under the toilet; once through an existing gland for a an AC outlet at the front of the propane housing, and again when installing a double gland for the two cables leading to my DC-DC charger mounted within the aft dinette seat hatch. Using a light and mirror while leaning into the forward seat hatch, enabled viewing of the outer hull wall beneath the toilet platform to pinpoint where a hole needed to be drilled to avoid plumbing.

View of AC outlet from inside housing.

Exterior view.

 

Double gland for DC-DC cable entry.

 

 

 

 

Edited May 20 by Ronbrink

[Galway Girl]

@rideadeuce here’s how the wires looked after installation:

The dc/dc charger output wire is the one with the red heat shrink on the end.

The trick was to use the right size lug on the end to match buss bar bolts.

The run was very short , < 2ft so a 6 x1/4” lug was used. 

[jd1923]

When I was first thinking about adding one of these, I assumed I needed an isolated converter to remove electrical interference between electronics in the TV (ECM, sensors, radio) and TT (solar charger, perhaps other).

This article recommends the non-isolated merely based on cost. It does not address nor give example of possible interference. Isolated vs non Isolated DC to DC Charger - Which one to get (cleversolarpower.com)

Then I installed a Pepwave router in the TV. I connected it directly to the TV battery. At first temporarily, thinking if there was interference with the router and ECM, I would just run the router when camped and eventually add an isolated AGM battery in the truck bed. I have not needed to do so. The TV with router on driving down the road has not shown any bleep of issue. We have received clean 5G while driving down the highway and no issue in the TV. BTW, I also have an Edge Juice w/ Attitude installed which is a supplemental ECM, with multiple sensors, gauges etc. and no interference between the Juice and Pepwave, of course all sharing the same TV ground

The more I think about it, while towing/charging most everything is off in the TT (except solar charger), so what kind of interference could there be? Can anybody provide example(s) of probable relevant interference? If not, the Victron 50A non-isolated charger should be just fine, just as @MAX Burner's installation has proved.