48v System Alternator Charging

[steves_ambo]

Hello,
I have a 2003 F450 ambulance that I'm converting into a camper. While designing and dreaming of how I want to do it, I started learning more about running a 48v house system vs 12v which I'm a little more familiar with. After Will's recent videos describing the benefits of going 48v, I think I'm convinced that's the way to go.
I understand the shore power and pv side well enough, but where I'm running into issues is charging from the car.
I did what any nerd would do and went to google and started searching for 48v alternators for a 6.0 powerstroke. I figured the truck already has two alternators, I could replace one with a 48v and I'd be set!
But, either my google foo is poor, or they don't really exist.

So, I guess I've got a couple of questions:
Does anyone know of a 48v alternator for a 6.0 powerstroke?
Is there some sort of device I can place in line between the 12v alternator and the dc/dc charger to "ramp" the voltage up to 48v?
Is there something I'm completely unaware of that is causing you to smack your forehead and utter I'm dumb under your breath?!

Thanks in advance!
Steve

 

[justinm001]

You want 1 or more Victron Orion DC to DC converters 12/48. You should have large enough alternators to have 100a+ (1200w)

48 volt alternators don't really exist. Balmar makes a 70a and 100a but they're a few grand. Newer jeeps and such have 48v alt but regardless you need to make it fit and even the you need a wakewpeed ws500 or Zeus or Balmar regulator that can regulate for LFP batteries.

 

[Bop]

Hello,
I have a 2003 F450 ambulance that I'm converting into a camper. While designing and dreaming of how I want to do it, I started learning more about running a 48v house system vs 12v which I'm a little more familiar with. After Will's recent videos describing the benefits of going 48v, I think I'm convinced that's the way to go.
I understand the shore power and pv side well enough, but where I'm running into issues is charging from the car.
I did what any nerd would do and went to google and started searching for 48v alternators for a 6.0 powerstroke. I figured the truck already has two alternators, I could replace one with a 48v and I'd be set!
But, either my google foo is poor, or they don't really exist.

So, I guess I've got a couple of questions:
Does anyone know of a 48v alternator for a 6.0 powerstroke?
Is there some sort of device I can place in line between the 12v alternator and the dc/dc charger to "ramp" the voltage up to 48v?
Is there something I'm completely unaware of that is causing you to smack your forehead and utter I'm dumb under your breath?!

Thanks in advance!
Steve

12v high capacity and 24v high capacity alternators are both extremely common, and quite cheap with 12v from cars, 24v from trucks making it worthwhile manufacturing them
48v- VERY rare and mega $$$ practically nobody uses 48v mobile- so why set up a manufacturing plant for them???
And running multiple voltages in the one vehicle- urgh- it's a nightmare...

My advice is simply stick to the voltage the vehicle original charging system is at- LFP can be directly charged from an alternator via a dual battery setup- you won't get a full charge on them, but you will get to 80% charge while driving around, any solar can take care of that last 20%, and in an emergency, you can always start the motor up and use it as an emergency 'generator'
It is unlikely that you will need power levels that can't be taken care of with a 12 or 24v system and be in a mobile situation...

I'm still on 12v- and I cook on all electric, run the shed and caravan (which was why I stayed with 12v at this point- for the vans lights, inbuilt TV and waterpumps) and run the welder and plasma cutter off a 8kw 12v inverter... somethin I doubt you'll be doing from a mobile vehicle so heavy loads can be accommodated with proper selection of battery bank and cabling...

 

[justinm001]

12v high capacity and 24v high capacity alternators are both extremely common, and quite cheap with 12v from cars, 24v from trucks making it worthwhile manufacturing them
48v- VERY rare and mega $$$ practically nobody uses 48v mobile- so why set up a manufacturing plant for them???
And running multiple voltages in the one vehicle- urgh- it's a nightmare...

My advice is simply stick to the voltage the vehicle original charging system is at- LFP can be directly charged from an alternator via a dual battery setup- you won't get a full charge on them, but you will get to 80% charge while driving around, any solar can take care of that last 20%, and in an emergency, you can always start the motor up and use it as an emergency 'generator'
It is unlikely that you will need power levels that can't be taken care of with a 12 or 24v system and be in a mobile situation...

I'm still on 12v- and I cook on all electric, run the shed and caravan (which was why I stayed with 12v at this point- for the vans lights, inbuilt TV and waterpumps) and run the welder and plasma cutter off a 8kw 12v inverter... somethin I doubt you'll be doing from a mobile vehicle so heavy loads can be accommodated with proper selection of battery bank and cabling...

You have to be careful running LFP directly off an alternator and more so of dual alternators.

8kw at 12v is over 600amps. What wiring, fuses and shunts are you using that handles over 600a safely? I know my lynx shunt and distributor can handle 1000a but damn.

In comparison the same 8kw load on 48v is like 160a which is easy to manage on 2/0 wiring and almost everything can easily handle that

 

[Bop]

You have to be careful running LFP directly off an alternator and more so of dual alternators.

8kw at 12v is over 600amps. What wiring, fuses and shunts are you using that handles over 600a safely? I know my lynx shunt and distributor can handle 1000a but damn.

In comparison the same 8kw load on 48v is like 160a which is easy to manage on 2/0 wiring and almost everything can easily handle that

Dual heavy duty truck starter motor cables in parallel for everything from the inverter to the 20kwh battery bank- this is one of my spare fuses (half a century old now lol) left over from my days as an apprentice elec fitter in the railways...

Quite handy really- the fuse has dual holes (one for each cable), the inverter has dual positive and negative posts on it and the battery bank (16x 400Ah LYP lithiums currently in 4S4P) has two sets of paralleled series cells feeding to each of those dual cables (I had to wire brush the one thats in use, 50 years of age and rolling around in the bottom of one of my toolboxes hadn't done them any favours as you can see)

No shunts, I just use voltage as a guide for 'rough' battery SOC (I know everyone says you can't do it with lithiums, but I can tell the SOC from the voltage even under load at night from experience- I know my 'usual' nightime load and what voltage corresponds to what SOC at that load...)
It's all just 'temporary' to run the shed and caravan until the house is finished, then it will be going to a 48v 16s bank at the house
It's all a bit 'play toy' level compared to my days at the railways- 1600vdc at 20kA, makes this setup look like a toy lol

 

[justinm001]

Dual heavy duty truck starter motor cables in parallel for everything from the inverter to the 20kwh battery bank- this is one of my spare fuses (half a century old now lol) left over from my days as an apprentice elec fitter in the railways...
View attachment 197142
Quite handy really- the fuse has dual holes (one for each cable), the inverter has dual positive and negative posts on it and the battery bank (16x 400Ah LYP lithiums currently in 4S4P) has two sets of paralleled series cells feeding to each of those dual cables (I had to wire brush the one thats in use, 50 years of age and rolling around in the bottom of one of my toolboxes hadn't done them any favours as you can see)

No shunts, I just use voltage as a guide for 'rough' battery SOC (I know everyone says you can't do it with lithiums, but I can tell the SOC from the voltage even under load at night from experience- I know my 'usual' nightime load and what voltage corresponds to what SOC at that load...)
It's all just 'temporary' to run the shed and caravan until the house is finished, then it will be going to a 48v 16s bank at the house
It's all a bit 'play toy' level compared to my days at the railways- 1600vdc at 20kA, makes this setup look like a toy lol

Not a chance I'd consider anything like that in a moving vehicle like OP. Theres just too much vibration and movement with limited space.

 

[Bop]

Not a chance I'd consider anything like that in a moving vehicle like OP. Theres just too much vibration and movement with limited space.

Funnily enough- Ive had the inverter in the ute since 2014, going offroading in it- I actually pulled it out of the ute to run the shed temporarily hence the battered appearance- it lived until 2020 in the bed of the ute running off its house batteries...

 

[mikefitz]

recent videos describing the benefits of going 48v

For a RV with modest power requirements, inverter under 3000 watts, there is little advantage.

 

[justinm001]

For a RV with modest power requirements, inverter under 3000 watts, there is little advantage.

3000w is still 250a vs 62a. There's no disadvantage for OP, he still needs DC to DC converters although he could get the new ORION XS 50a ones. I'd kinda suggest going 24v if under 5000w as the Orion 12/24 are 70 and boost to 85a for like the same price of a 30a 12/12 or 12/48.

 

[steves_ambo]

Thanks for the info and discussion, guys!

I'm wondering if I wouldn't be better served just sticking with 12v. My demands, at least as I'm listing them off in my head, aren't going to be that crazy. Largest draws would probably be induction cooktop, microwave and maybe a toaster oven.
I don't plan on running a welder or anything.

For a RV with modest power requirements, inverter under 3000 watts, there is little advantage.

I think I'm in this boat (or camper ).
The idea of 48v is pretty cool, but like you said, for the size of system I will have, probably not worth it.

In my poking around, I did come across this thing which is pretty neat.
Looks like you can only order it from the UK.
Might be helpful for someone looking to do what I am.

Sterling Power - 12V (ONLY) TO 48V BATTERY TO BATTERY CHARGER


ETA: I forgot to mention that I will likely have an AC unit at some point.
I have not decided if I will go 12v or 120v minisplit style.
I'm sure there is a thread or two discussing those somewhere on this forum that I haven't found yet.

 

[Bop]

Thanks for the info and discussion, guys!

I'm wondering if I wouldn't be better served just sticking with 12v. My demands, at least as I'm listing them off in my head, aren't going to be that crazy. Largest draws would probably be induction cooktop, microwave and maybe a toaster oven.
I don't plan on running a welder or anything.



I think I'm in this boat (or camper ).
The idea of 48v is pretty cool, but like you said, for the size of system I will have, probably not worth it.

In my poking around, I did come across this thing which is pretty neat.
Looks like you can only order it from the UK.
Might be helpful for someone looking to do what I am.

Sterling Power - 12V (ONLY) TO 48V BATTERY TO BATTERY CHARGER


ETA: I forgot to mention that I will likely have an AC unit at some point.
I have not decided if I will go 12v or 120v minisplit style.
I'm sure there is a thread or two discussing those somewhere on this forum that I haven't found yet.

None of those are particularly high draw and can all be run on a 12v system with ease... (apart from the A/C of course)
Sterling is a well known brand here in Australia (mostly for their 24v to 12v converters used in trucks to run 12v stuff)
Obviously my inverter has no issues with running such stuff (lol- I can run all at once even) but a 2400w 12v inverter will handle any of them with ease (its better to have a bigger inverter running 'lazy' than a smaller one running 'flat out' for reliability) and thats only 200A, which is less than most cars draw on starting- use premade 'heavy duty starter cables', keep 'em short and you will have no issues at all... (you can get premade starter cables at any auto store, in a variety of lengths and thicknesses, with either a battery terminal at one end, and a lug at the other, or lugs both ends... saves trying to crimp or solder them yourself...)

iik

 

[mikefitz]

Looks like you can only order it from the UK.
Might be helpful for someone looking to do what I am.

Sterling Power USA

battery charger, marine battery charger, 12v marine battery charger, DC to DC battery charger, smart charger, bassboat charger, agm battery charger, optima battery charger, sterling pro charge ultra, multistage charge while driving, pfc battery charger, sterling power, waterproof battery...

www.sterling-power-usa.com

 

[RV8R]

Thanks for the info and discussion, guys!

I'm wondering if I wouldn't be better served just sticking with 12v. My demands, at least as I'm listing them off in my head, aren't going to be that crazy. Largest draws would probably be induction cooktop, microwave and maybe a toaster oven.
I don't plan on running a welder or anything.



I think I'm in this boat (or camper ).
The idea of 48v is pretty cool, but like you said, for the size of system I will have, probably not worth it.

In my poking around, I did come across this thing which is pretty neat.
Looks like you can only order it from the UK.
Might be helpful for someone looking to do what I am.

Sterling Power - 12V (ONLY) TO 48V BATTERY TO BATTERY CHARGER


ETA: I forgot to mention that I will likely have an AC unit at some point.
I have not decided if I will go 12v or 120v minisplit style.
I'm sure there is a thread or two discussing those somewhere on this forum that I haven't found yet.

Hi @steves_ambo

IMO, these decisions can only be made after you know your needs / wants, “load calculations”, preliminary design, etc.

But, that being said, the equation you are boils down to harvesting as much energy outta whatever alternator you will use while not burning out your alternator. I am more of an electrical minimalist, but if I were to look at this for myself I would look at the big RV rigs out there & sort out what they do & why ,,, My ignorant self believes without research it is an onboard Gen Set.

I floundered with my van wanting 100% electric. All things heat takes energy ( so does A/C ). I finally looked @ the RV Industry for energy , I carry propane & charge up my efficient 12vdc electrical system with the 220a factory alternator harvesting 50a or about 700w max when needed.

1 20lb propane tank has the same energy stored in it as 116 - 100Ah 12vdc lithiums.

 

[Bop]

Hi @steves_ambo

IMO, these decisions can only be made after you know your needs / wants, “load calculations”, preliminary design, etc.

But, that being said, the equation you are boils down to harvesting as much energy outta whatever alternator you will use while not burning out your alternator. I am more of an electrical minimalist, but if I were to look at this for myself I would look at the big RV rigs out there & sort out what they do & why ,,, My ignorant self believes without research it is an onboard Gen Set.

I floundered with my van wanting 100% electric. All things heat takes energy ( so does A/C ). I finally looked @ the RV Industry for energy , I carry propane & charge up my efficient 12vdc electrical system with the 220a factory alternator harvesting 50a or about 700w max when needed.

1 20lb propane tank has the same energy stored in it as 116 - 100Ah 12vdc lithiums.

Many US RV's use a genset- they really haven't been a 'thing' outside the US for decades...
(mostly because in many places their use is either banned outright or limited to specific hours of the day only- noone wants to go to a nice camping spot and have to listen to some bloody genpack droning away 24/7- urgh- here you would be 'politely' asked to bugga off with it- or have your mechanic do the next oil change with a glove and lots of lube...)

Motorhomes (and 4wds towing caravans, which is more common here) use battery packs (these days lithiums are standard new from the factory in many caravans) use slightly modified alternators- there's nothing needs doing internally to them in most cases (with many having 120A-150A alternators straight from the factory these days), but most alternators cooling fans are c..p which is why they fail when fitted with large capacity second 'house banks'- it is common to fit decent cooling fans to them (which can often be done without even removing it from the engine bay...)

Take off the factory piece of bent tin and fit a diecast or milled high volume fan like this...

LPG (propane/butane) has fallen out of favour in the industry here, with onboard solar and lithiums batteries taking over simply because of the cost of LPG to begin with (my caravan from the early 70's had provision for twin 7kg bottles- first thing I did was cut the brackets off and the metal hoses off- that halved the yearly rego straight away (lpg fitted caravans have a much more expensive rego than 'habitable trailers' ie identical but no LPG fitted) and meant I no longer had to have an annual inspection done on it either (close to $100 a year and meant having to take the annex down and tow it into town to an LPG inspection station, none did a 'come to you' one, they all wanted you to take it to them) plus each 7kg bottle is currently about $30-35 each to fill...

 

[justinm001]

Hi @steves_ambo

IMO, these decisions can only be made after you know your needs / wants, “load calculations”, preliminary design, etc.

But, that being said, the equation you are boils down to harvesting as much energy outta whatever alternator you will use while not burning out your alternator. I am more of an electrical minimalist, but if I were to look at this for myself I would look at the big RV rigs out there & sort out what they do & why ,,, My ignorant self believes without research it is an onboard Gen Set.

I floundered with my van wanting 100% electric. All things heat takes energy ( so does A/C ). I finally looked @ the RV Industry for energy , I carry propane & charge up my efficient 12vdc electrical system with the 220a factory alternator harvesting 50a or about 700w max when needed.

1 20lb propane tank has the same energy stored in it as 116 - 100Ah 12vdc lithiums.

You're spot on propane is much better at energy storage. High end large coaches are usually all electric but thats because its easier to maintain and use, plus almost all are configured to be on 50a shore 24/7 and/or genset 24/7. My prevost has a 20kw genset and has a sticker on the engine saying hourmeter to subtract 22,000 hours and on the control panel to add 12,000 hours as both have been replaced and its just easier to run genset the entire time. I even looked at entertainer (tour bus) coaches and many of them have 2 20kw gensets, just incase one dies.

 

[steves_ambo]

Hi @steves_ambo

IMO, these decisions can only be made after you know your needs / wants, “load calculations”, preliminary design, etc.
...

1 20lb propane tank has the same energy stored in it as 116 - 100Ah 12vdc lithiums.

Thanks for the reply.

I'm wondering if I should do a brain dump of my current plans for the electrical, equipment, loads etc and have the crowd do a sanity check.
Wondering if I should do that here or start a proper intro thread in this sub-forum.

Many US RV's use a genset- they really haven't been a 'thing' outside the US for decades...
(mostly because in many places their use is either banned outright or limited to specific hours of the day only- noone wants to go to a nice camping spot and have to listen to some bloody genpack droning away 24/7- urgh- here you would be 'politely' asked to bugga off with it- or have your mechanic do the next oil change with a glove and lots of lube...)

The type of camping I do is to 100% get away from people running gensets (is that the plural? We call them generators here, lol)
If I'm desperate, I have a generator in the form of my diesel motor! Goal is to not be desperate.

You're spot on propane is much better at energy storage. High end large coaches are usually all electric but thats because its easier to maintain and use, plus almost all are configured to be on 50a shore 24/7 and/or genset 24/7. My prevost has a 20kw genset and has a sticker on the engine saying hourmeter to subtract 22,000 hours and on the control panel to add 12,000 hours as both have been replaced and its just easier to run genset the entire time. I even looked at entertainer (tour bus) coaches and many of them have 2 20kw gensets, just incase one dies.

I feel like the "enlightened" vanlife people want to go all electric for everything.
But, propane does have it's uses. For me, hot water for washing dishes and especially showers is a no brainer for propane.
In the US, we all kind of agreed on a 20# standard propane cylinder. They are ubiquitous at nearly every gas (petrol) station. You just empty your cylinder, and then you exchange it for a new one for $20-25. You can also refill your propane tanks, but there aren't as many places that do that.

 

[justinm001]

Thanks for the reply.

I'm wondering if I should do a brain dump of my current plans for the electrical, equipment, loads etc and have the crowd do a sanity check.
Wondering if I should do that here or start a proper intro thread in this sub-forum.


The type of camping I do is to 100% get away from people running gensets (is that the plural? We call them generators here, lol)
If I'm desperate, I have a generator in the form of my diesel motor! Goal is to not be desperate.



I feel like the "enlightened" vanlife people want to go all electric for everything.
But, propane does have it's uses. For me, hot water for washing dishes and especially showers is a no brainer for propane.
In the US, we all kind of agreed on a 20# standard propane cylinder. They are ubiquitous at nearly every gas (petrol) station. You just empty your cylinder, and then you exchange it for a new one for $20-25. You can also refill your propane tanks, but there aren't as many places that do that.

Technically a genset is an engine and a generator. A generator is just the part that creates energy, so larger systems are called genset as usually they're 2 separate pieces just combined.

 

[RV8R]

Thanks for the reply.

I'm wondering if I should do a brain dump of my current plans for the electrical, equipment, loads etc and have the crowd do a sanity check.
Wondering if I should do that here or start a proper intro thread in this sub-forum.


The type of camping I do is to 100% get away from people running gensets (is that the plural? We call them generators here, lol)
If I'm desperate, I have a generator in the form of my diesel motor! Goal is to not be desperate.



I feel like the "enlightened" vanlife people want to go all electric for everything.
But, propane does have it's uses. For me, hot water for washing dishes and especially showers is a no brainer for propane.
In the US, we all kind of agreed on a 20# standard propane cylinder. They are ubiquitous at nearly every gas (petrol) station. You just empty your cylinder, and then you exchange it for a new one for $20-25. You can also refill your propane tanks, but there aren't as many places that do that.

You are welcome @steves_ambo

“The Enlightened” ,,, Ya maybe. My 1st van build in 2018 I wanted to go 100% electric, until I did the math. I didn’t want my wallet to be “Enlightened”

In Canada, we buy propane at an honest “fill” rate @ Costco which changes as the cost if propane changes, but usually $14 to $17 CAN for a fill from totally empty.

If you do a “load calculation & daily estimated energy spreadsheet”, I can show you how propane can help with “All Things Heat”.

1 - 20lb BBQ Tank
vs
116 - 100Ah 12vdc LFP Batteries

Your Choice


Here are some spreadsheets I have done calculations / estimates for energy use to give you some examples;







Some of the information in the above examples is incomplete ( so rough idea only for you to help you with your unique situation / build ).

 

[RV8R]

IMO;

A used Ambulance size converted into an RV should be maximum 24vdc, or stick with your “ship’s power of 12vdc.

It should use propane for “All Things Heat”

But the above would be based upon “My” use which is “Travel” & never really hooked up to “Shore Power” & basically “Boondocking”. No solar on our “Travel Van”.

To give you better recommendations, I would have to know more about your intended use.


In 2018, when I had intentions to go 100% electric ( because all the cool kids had it ), I floundered about. Finally I looked at the RV industry ,,, I estimate a large majority of RVs out there have propane. At home we cook with natural gas , & we are tied into the grid & heat via electricity “heat pump”.

Now I do not understand why Van DIYers don’t use propane more often. For me it is an equation of efficiency & economics.

Depending upon the wind resistance or “ slipperiness” of the van; I burn less gasoline charging by alternator then by roof mount Solar Panels that disturb the laminar airflow of my van ( solar panels are always degrading my highway MPG ,,, Alternator Charging only uses gasoline when charging up my house batteries ) ,,, & we are not Slaves to The Sun. On hot days, we can park in the shade .

Your Intended Use ,,, Really Matters to “The Equation”.

 

[Built.Vns]

48V alternators are absolutely available and are becoming more and more popular. Winnebago and Storyteller Overland are going 48V. I just installed a 48V electrical system in a clients Sprinter van with a 48V alternator for charging. I will be doing the same system in my personal van. Check out Nations Starter alternator.