dc/dc charger

[4everlooking]

Looking for the expertise from the group. I would like to put in the Orion xs 50 DC/DC. For my 2022 Ram LB CC I am about 22'. I'm estimating needing about 55' of wire including ground all the way back. I believe that 4 gauge will suffice, what say you experts?

Next question, The Orion can be put in parallel with more than one charger, effectively doubling the capacity from 50 to 100 amps. Will the 4 gauge be sufficient or would a larger wire be needed from the trucks battery to the charger? I've seen you tube video's showing the addition of the charger but haven't heard anything about needing larger wire. I would like to do the truck wiring once and have the capability to expand.

I should also note that the truck has twin 225 amp chargers so I should have enough to power the 2 orions without doing any damage.

Thanks for any and all knowledge.
Larry

[d23haynes57]

Why does your truck have 2–225-amp alternators? Wow!
What is the size of the battery pack and what connected loads in the trailer do you need to run while charging the batteries? How fast do you want to charge the batteries? Are you looking to quick charge a large bank in place of having a generator?

[TravelSolo]

Originally Posted by d23haynes57

Why does your truck have 2–225-amp alternators? Wow!
What is the size of the battery pack and what connected loads in the trailer do you need to run while charging the batteries? How fast do you want to charge the batteries? Are you looking to quick charge a large bank in place of having a generator?

All of this. I have a 40A DC-DC and between it and the solar, I am usually fully charged by the time I am done driving the next leg. But I also am rarely below 40% capacity (out of 400Ah) so 4-5 hours of driving in daylight gets me topped off.

[4everlooking]

Originally Posted by d23haynes57

Why does your truck have 2–225-amp alternators? Wow!
What is the size of the battery pack and what connected loads in the trailer do you need to run while charging the batteries? How fast do you want to charge the batteries? Are you looking to quick charge a large bank in place of having a generator?

I ordered the truck from the factory with the 2-225 alternators. I wanted to be able to power anything in the future, therefore maybe some overkill. For instance the truck is a 1 ton pulling a 600# +/- trailer, but I wanted to be able to get bigger if I wanted to. My next one will likely be an Outdoors trailer, weighing in at 11,000 max gross. I'm rated for 27,000# + for towing, again overkill, but I like the safety involved with that. Just me.

I'm looking at 900-1200 AH of battery, 2000 watts rooftop solar, up to 600 watts portable solar & a 3600 watt propane generator. Did I mention that I like overkill and redundancy. The dc/dc is just another way to make sure I am powered up no matter what.

Larry

[4everlooking]

Originally Posted by TravelSolo

All of this. I have a 40A DC-DC and between it and the solar, I am usually fully charged by the time I am done driving the next leg. But I also am rarely below 40% capacity (out of 400Ah) so 4-5 hours of driving in daylight gets me topped off.

The real life situations you speak of are of great value to me. Thanks. I am only thinking of the dual orions for those rare times where something went wrong and the batteries are really low, emergency charging or the annihilations of the grid system causing all solar activity to cease. I want to be there with the lights on I guess.

I wasn't sure if thicker wiring on the truck side was needed to add on the additional amperage.

Larry

[d23haynes57]

Originally Posted by 4everlooking

I ordered the truck from the factory with the 2-225 alternators. I wanted to be able to power anything in the future, therefore maybe some overkill. For instance the truck is a 1 ton pulling a 600# +/- trailer, but I wanted to be able to get bigger if I wanted to. My next one will likely be an Outdoors trailer, weighing in at 11,000 max gross. I'm rated for 27,000# + for towing, again overkill, but I like the safety involved with that. Just me.

I'm looking at 900-1200 AH of battery, 2000 watts rooftop solar, up to 600 watts portable solar & a 3600 watt propane generator. Did I mention that I like overkill and redundancy. The dc/dc is just another way to make sure I am powered up no matter what.

Larry

So, how are those alternators wired, being utilized? Are they both in parallel or are they feeding different systems? Maybe one for the truck and the other for trailer or other defined loads?
Are you looking to charge depleted batteries while traveling or just topping off and maybe running some appliances like a refrigerator while driving? For 1,200 A/H battery bank 50 amps puts you at a 24-hour rate. With all that alternator capacity a voltage-controlled isolator relay or diode block could be a better solution.

For my Nimbus I upgraded from 600 A/H AGM to now 880 A/H lithium. No mods for engine alternator charging. I have 270 A/H alternator, and a diode set up is used for isolating chassis and house batteries. The alternator has remote sensing on the chassis batteries only. This works out perfectly. Starting the engine, I see just over 14 volts on the chassis batteries and ~13.8 on the Lithium hose bank pulling about 160 amps. This tapers down after a few minutes to 130-140 amps and voltage rises. After a few hours as the batteries approach full charge, the battery BMS tapers down the current and voltage rises further to match the chassis batteries. If I drive long enough the batteries BMS will turn charging off and they will then only use current to maintain the BMS, about .045 amps for the 3 batteries. If I want faster charging, I can also start the generator and the 150 A/H charger in the inverter charger will add almost another 100 A/H to the charge rate taking some load off the alternator.

[SafariBen]

With 55' of 4g, I'd skip the DC to DC. If you draw 100A the voltage drop will limit the current just fine. Probably be lucky to get over 50A. The DC to DC stepping up the amps will cause 25% voltage drop if it can pull that much power at 10v?

[B-Man]

Originally Posted by 4everlooking

Looking for the expertise from the group. I would like to put in the Orion xs 50 DC/DC. For my 2022 Ram LB CC I am about 22'. I'm estimating needing about 55' of wire including ground all the way back. I believe that 4 gauge will suffice, what say you experts?

Next question, The Orion can be put in parallel with more than one charger, effectively doubling the capacity from 50 to 100 amps. Will the 4 gauge be sufficient or would a larger wire be needed from the trucks battery to the charger? I've seen you tube video's showing the addition of the charger but haven't heard anything about needing larger wire. I would like to do the truck wiring once and have the capability to expand.

I should also note that the truck has twin 225 amp chargers so I should have enough to power the 2 orions without doing any damage.

Thanks for any and all knowledge.
Larry

To answer your question about the wire gauge:

1. At 50 amps draw you will realize about 5.1% voltage drop. Your truck will likely output 14.7 volts so the voltage at the DC/DC charger will be roughly
13.95 volts.

2. At 100 amps draw the voltage drop is double - about 10.2% so the voltage at the DC/DC charger will be roughly 13.2 volts.

You need to measure the voltage at the batteries with the engine running, headlights on, AC on, etc. With a load on the electrical system you will get a better feel for how the alternators behave. You can use a high-idle to test the output to better simulate what you will get when driving.

I ran a 1/0 cable for my setup. I use the truck frame for the negative connection though. I power a winch, jump start vehicles, charge my RV, etc. with this setup. I installed a Trailer Vision mount for the Anderson connectors I use for quick connections. One in the front of the truck and the other at the rear. No alligator clamps on battery terminals for me.

https://www.amazon.com/Trailer-Visio...09KCGKLPM?th=1

[4everlooking]

You need to measure the voltage at the batteries with the engine running, headlights on, AC on, etc. With a load on the electrical system you will get a better feel for how the alternators behave. You can use a high-idle to test the output to better simulate what you will get when driving.

I ran a 1/0 cable for my setup. I use the truck frame for the negative connection though. I power a winch, jump start vehicles, charge my RV, etc. with this setup. I installed a Trailer Vision mount for the Anderson connectors I use for quick connections. One in the front of the truck and the other at the rear. No alligator clamps on battery terminals for me.

https://www.amazon.com/Trailer-Visio...09KCGKLPM?th=1[/QUOTE]

Are you saying to check the voltage while plugged into the trucks 7 pin cable?

If I use the truck frame for the negative connection, doesn't that length still count for total distance?

Thanks for the heads up on the Trailer Vision. I like the looks of it. I do however need to figure out if the SB50 is adequate or if I need to step up to the SB120 for future if I double the Orion's.

Larry

[hclarkx]

Mostly answered, but if it's not too late ..........

55 feet of #4 will have 0.253 x 55/1000 or 0.014 ohms (at 25C or room temp -- higher at 75C). That's one-way. Let's assume the same resistance in the return via the truck and RV frame (might be optimistic). So, 0.028 ohms. 100 amps would cause 2.8 Volts drop. Probably more with terminals and higher temp in the wire.

If the DC-DC is in the truck you will have almost 3 V less than the DC-DC output at the batteries. So, 11 volts instead of 14 volts. That won't do any charging.

If the DC-DC is at the batteries, it will cover that voltage drop and do the job. Most DC-DC will work with as low as 10 volts or less input. Keep in mind that 100 amps out would require 14/10 or 140 amps input to the DC-DC. That makes the #4 too small from a thermal standpoint.

So, it's essential that the DC-DC be close to the batteries. And #4 is on the small side voltage-drop-wise and definitely too small from a thermal standpoint if you are going for 100 amps.

Also, that 100 amps becomes 140 amps at the alternators. Will each one handle other load plus 70 amps?

[Stircrazy1]

so looking at the wire chart for a 56 foot run (there and back) rounded to 60 feet, you need 0 gauge to have a 3% loss or less, what you were looking at is a no critical circuit where a 10% drop is acceptable.

so keep in mind that your dc to dc charger should be placed at the battery so the more drop you are allowing through the wire the higher the draw is going to be on the battery and alternator. so your 50amp dc to dc charger may draw 60 to 75 amps to make the proper voltage output at 50amps for the battery.

so for this example if you are charging a Li profile with the dc to dc at 14.6V 50 amps (730watts) . and your alternator is putting out 13.2V and you have a 10% line drop that means the dc to dc is only seeing about 11.8V and has to compensate by drawing about 62 amps to make the proper output voltage and amperage. if you went with the 0 awg then with a 3% drop it sees 12.8V and only has to draw 57amps. if you size it larger you can get it down to a 1% but then its a case of weather or not your altanator can handle the draw ok and weather you want to spend more money on the wire. in fact your at that point with the 4awg anyways. if you can handle up to 70 or 75 amps now issues then ya go with it. if your worried about it go with bigger wire.

[4everlooking]

hclarkx and stircrazy1 thanks for the accurate detailed description. It allows my electrical feeble mind to read and reread to soak in the details. On my future rig where the 1 or 2 Orions would go, they will be located next to the batteries with minimal distance.

As far as the truck goes, probably will use 4awg for the run. I would check with the dealership about the twin alternators being able to handle the extra load, but the dealerships wouldn't have a clue I'm afraid. They want me to believe that my engine block heater and heated steering wheel not working till it gets below 25 is normal. Ain't buying it.

Thanks again for all the helpful comments.
Larry

[hclarkx]

Originally Posted by 4everlooking

hclarkx and stircrazy1 thanks for the accurate detailed description. It allows my electrical feeble mind to read and reread to soak in the details. On my future rig where the 1 or 2 Orions would go, they will be located next to the batteries with minimal distance.

As far as the truck goes, probably will use 4awg for the run. I would check with the dealership about the twin alternators being able to handle the extra load, but the dealerships wouldn't have a clue I'm afraid. They want me to believe that my engine block heater and heated steering wheel not working till it gets below 25 is normal. Ain't buying it.

Thanks again for all the helpful comments.
Larry

You are welcome. My inclination would be to use a DC clamp-on meter to see what the load is on the alternators. This would only be a standstill test obviously, but you could raise the idle with various loads turned on, individually or all together to get an idea of the load (A/C, headlights, etc.).

Though if you stick with #4, you are limited to a 50 amp DC-DC unit (60 or 70 amps at the alternator) and with dual alternators there's surely enough unused capacity for that.