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Who makes a 12v to 48v (56v) converter?

Dave in AZ

Solar Enthusiast
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Dec 6, 2023
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Phoenix
Victron only has 12v to 24v.

For running a powerstation in a truck bed, there is no need for a full dcdc smart charger, as the powerstation already has its own "smart input" in all cases. Rather, all that is needed is a 12v to ??? Converter, where the ??? Matches the powerstation dc input.

Most power stations have an mppt input for EITHER solar, or a 12v input from a car port. Most will accept a range of voltage, say 11v - 95V, but are limited on the amps and watts allowed. If you convert from 12v to 48v, it allows more of the allowed watts to be input.

A 12v to 48v converter, 56v actual converter, would have many uses for car charging of power stations. Would need to allow 400W power around, so 30A on the truck or car 12.8V system, which should be supportable by most alternators.
I can't find one, besides 5A cheap $15 noname on Amazon. Anyone?
 
Only 48v converter I see victron making is their 24 48 120W thing.
Just looked at this solution: Victron say their Orion TR 12 24, and 24 48 ones, can be paralleled unlimited. So the 120W ones are $64...
120w: 12v >> 24 v, 24v >> 48v for $128
Parallel 3 for $384, 360W delivered up to 60v as they are adjustable.

Or their 12 24 20A converter, $140 for 480W. Then run 4 of the 24 48 120W
 
I have this little beast:

Also used by Andy from Off-Grid-Garage on YT.
It can boost up to 60v.
Although it's a cheap Chinese device, it's pretty capable and reliable if you don't push it to it's limits.
I hope this helps.
Hmm... 20A max input, so 12v x 20A, 240W. Could parallel 3, set them for 140W, 11A or so.

Problem with this kind of thing is trusting to hook it to your expensive and delicate car electrical system. Do I trust it not to spike my system and burn out my ECU etc somehow?? Not really... When connecting to my $50k car/electrical, I kind of want an instruction sheet in English and reliable testing.

What are you doing with it? Connected to car?
 
Hmm... 20A max input, so 12v x 20A, 240W. Could parallel 3, set them for 140W, 11A or so.

Problem with this kind of thing is trusting to hook it to your expensive and delicate car electrical system. Do I trust it not to spike my system and burn out my ECU etc somehow?? Not really... When connecting to my $50k car/electrical, I kind of want an instruction sheet in English and reliable testing.

What are you doing with it? Connected to car?
I'm with you. I wouldn't trust a device like this with expensive gear on either side. Unless there's some way to protect against voltage spikes. I've already fried 10k+ of electronic gear when my alternator spiked to 16v. Also the battery BMS doesn't help as I've fried those too
 
Hmm... 20A max input, so 12v x 20A, 240W. Could parallel 3, set them for 140W, 11A or so.

Problem with this kind of thing is trusting to hook it to your expensive and delicate car electrical system. Do I trust it not to spike my system and burn out my ECU etc somehow?? Not really... When connecting to my $50k car/electrical, I kind of want an instruction sheet in English and reliable testing.

What are you doing with it? Connected to car?
First, I think it's rated at 30 amps, not 20.
Second, if you are worried about voltage spike backfeeding into your 12v system, you could add a diode on the input. It could be a standard Schottky diode, or an ideal diode (MOSFET based) but with less power losses.

I had it connected to my 12v socket in the car to charge up a 24v battery. But I limited the current because of the socket.

Other than that I have used it here and there...
 
The newest “Thang” from EcoFlow;


But I think Inwould prefer “The Orton Method”

12vdc alternator / 120vac Inverter / AIO wall charger.

The trick is to limit the power from the alternator ,,, depending upon the alternator & what it can provide. Also, a “cockpit” controllable On/Off switch to not utilize in (engine idle) stop & go traffic etc or when the truck is in need of the alternator.

The Achilles’ Heel of these AIO boxes has been their dependency on wall charging 120vac for any real kinda of decent charge rate.

Now that EcoFlow has seen the gap & has this new alternator charger, I would expect all of the AIO unit manufacturers to follow suit & build their own proprietary alternator chargers.

Still ,,, I would be using the Orton method (alternator / inverter / 120vac AIO wall charger) to setup an AIO, for several reasons, but one reason being 120vac for that charger doesn’t really care about the 120vac wire size run (the 12vdc cables to the inverter from the starter battery should be as close as possible & big).

I’m not interested in AIO units, but I do have a 12vdc to 12vdc DC2DC Kisae 1250. It is very user programable & I can dial in whatever power draw I want from about 70W to 700W in 5amp incremental current settings for my AGMs in my 220amp alternator equipped Promaster Van.


Welcome to the “Proprietary World” of AIOs 😁. We sell them “relatively cheap” & then get cha on the proprietary peripherals 😜.
 
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Pecron just introduced an alternator converter, 500W, does 12v to 42v for input to their power station solar inputs. Done deal.

Just looked that up ,,, this one ?



IMG_8908.jpeg


42v “output” voltage ,,, that works for you ?
 
I'm looking for something similar. I just bought a bluetti ac200p for my parents. I want to set it up in my Dad's vehicle for both solar and alternator charging simultaneously. The problem is that the bluetti uses the same input for solar charging and vehicle charging. It has another input for AC charging with the external AC power brick. I could potentially use that for the vehicle charging but I would need a dc to dc converter to step 12v up to 58v. Plenty of 12v - 48v options but without actually buying one I don't know if they'll out put exactly 48v or something higher more like a 48v battery.
The easiest option I can find is to buy the bluetti D050S "DC charging enhancer", use that for the solar charging through the input for the AC charger, and the do the vehicle charging through the solar/vehicle input. I was hoping not to have to spend another ~$200 though.
 
The easiest way is to buy an inverter and hook it up to your starter battery.

Set it up to turn on / off when the engine turns on / off.

Plug the power station (what ever brand that you like ) into the inverter to charge it while driving.

Set the power station to charge at a rate that matches what your vehicle can support. Usually most vehicles can support 400 - 500 watts or so. Some can support more.
 
The easiest way is to buy an inverter and hook it up to your starter battery.

Set it up to turn on / off when the engine turns on / off.

Plug the power station (what ever brand that you like ) into the inverter to charge it while driving.

Set the power station to charge at a rate that matches what your vehicle can support. Usually most vehicles can support 400 - 500 watts or so. Some can support more.
This is a dangerous approach, if you pull more than the truck can handle itll drain and cause major issues. Low voltage in vehicles cause all kinds of issues.

Plus dc to ac to dc losses. And if any issues like it somehow not turning off you just killed the starter battery and dead in the water
 
I have considered the inverter approach. I haven't seen any inverters though that are intended to be turned on and off with the ignition of a vehicle. I'm sure it can be made to work, either by killing the 12v supply with a big relay, or replacing the on/off switch with a small relay (as long as it has a proper switch and not a push button).
I don't really care about the inefficiencies (what's a few more percent loss when we're making power with an inefficient automotive alternator driven by an inefficient petrol or diesel engine?), but it seems like such an inelegant solution, and with my experience with low cost inverters, probably not super reliable.
 
This is a dangerous approach, if you pull more than the truck can handle itll drain and cause major issues. Low voltage in vehicles cause all kinds of issues.

Plus dc to ac to dc losses. And if any issues like it somehow not turning off you just killed the starter battery and dead in the water

It is actually a very common method used in conversion vans for charging house battery packs.

A common setup in a conversion van is to have solar charging and 120 vac charging from a grid connection.

The choice then becomes - what is the easiest way to pull power from the alternator (s ), or if at all.

There are BTB chargers and they work well, but they still need to be designed / selected to operate within the capabilities of the alternator, and have a way to shut off when the engine is off. An example is a low voltage disconnect. The challenge is that you can't always get a BTB charger that matches the alternator capabilities.

If instead you match the 120 vac - DC battery pack charger so that it matches the capabilities of the alternator, then you can be pretty certain that it will not over load the alternator.

Some kind of on / off charging mechanism is still needed no matter the method. On Ford Transits, they often have this already built in to the side of the seat, or have place where you can get the signals to switch on / off an inverter or relay.

It takes a decent quality inverter to make this work, but it does in fact work much better than you might think. I had some real doubts about the approach for a while, but after working with it and testing some BTB chargers vs this method - it is surprisingly consistent and decent.

it also eliminates the question of "vehicle DC voltage" vs "battery pack voltage", as it does not matter.

The goal should be to pull a reasonable amount of power from the alternator, taking into consideration the total loads and heat effects, not to max it all out to the crazy end of the scale.

It is a good solution for the 0.5 - 1.5 kW ish range, not the 3 - 5 kW range.
 
It is actually a very common method used in conversion vans for charging house battery packs.

A common setup in a conversion van is to have solar charging and 120 vac charging from a grid connection.

The choice then becomes - what is the easiest way to pull power from the alternator (s ), or if at all.

There are BTB chargers and they work well, but they still need to be designed / selected to operate within the capabilities of the alternator, and have a way to shut off when the engine is off. An example is a low voltage disconnect. The challenge is that you can't always get a BTB charger that matches the alternator capabilities.

If instead you match the 120 vac - DC battery pack charger so that it matches the capabilities of the alternator, then you can be pretty certain that it will not over load the alternator.

Some kind of on / off charging mechanism is still needed no matter the method. On Ford Transits, they often have this already built in to the side of the seat, or have place where you can get the signals to switch on / off an inverter or relay.

It takes a decent quality inverter to make this work, but it does in fact work much better than you might think. I had some real doubts about the approach for a while, but after working with it and testing some BTB chargers vs this method - it is surprisingly consistent and decent.

it also eliminates the question of "vehicle DC voltage" vs "battery pack voltage", as it does not matter.

The goal should be to pull a reasonable amount of power from the alternator, taking into consideration the total loads and heat effects, not to max it all out to the crazy end of the scale.

It is a good solution for the 0.5 - 1.5 kW ish range, not the 3 - 5 kW range.
The problem is an inverter will pull whatever the load is as long as it's below its limit, and an alternator can only pump out so much power and puts out a bunch less at idle or when not moving.

This means if you're pulling say 1500w from the inverter and stuck in traffic at night with other things pulling power from the alternator like headlights, radiator fan and such then the alternator might only have 1000w additional to put thus the inverter is draining your starter battery. Then by the time the low voltage shutoff hits at 11v or whatever on the inverter your entire van is running at or under 11v and causing all kinds of electrical problems and can easily fry equipment. If the battery voltage is low at the inverter then it's much lower all around the van as many sensors and modules use thin wiring.

On top of all this if the alternator is pumping a ton of power into the inverter then it shuts off you can easily get a voltage spike and the opposite effect where your tossing high volts and can fry the alternator or other equipment.

I wouldn't trust how conversion vans do things as many times they cut as many corners as possible to keep costs down. Even the cheap RVs don't do this because too much risk of damage or someone draining starter battery and being left stranded
 
I can understand what you are describing @justinm001

Do you have any experience with alternator charging house batteries; DC2DC / Inverter / Alternator Direct ?

DIY Van Building is a process of research, design, & build. IMO also “Experimental” somewhat like Experimental in Aviation ,,, just unregulated & the vehicle is already licensed & operational.

To research Alternator Charging of House Batteries of “Any Kind”, a DIYer should get the specification of “available” excess power from the Vehicle Manufacturer that factory alternator can provide & the parameters of that. Good Luck 😁.

I can tell you Promasters come with 180a or 220a alternators ( 220a are for RV & Ambulance ) upfitters. Thru The Promaster Forum, the manufacturer’s factory loads have been presented ( it is like pulling teeth with Ram ). The 180a barely satisfies the Promaster’s factory equipment requirement if everything is on.

Near Death Valley & other areas where extreme heat occurs or heat & steep highways I have seen highway signs telling drivers to turn off their air conditioning 😁.

Are you against Inverter Alternator Charging house batteries or all stock alternator charging house batteries ?

Internal regulators that are part of most modern alternators are typically stamped with “D, C, or S”. These are sensor (typical male spade connectors). I would assume most modern vehicle regulators are “C” which means computer controlled. A DIY would have to obtain ( very unlikely ) the manufacturer’s software parameters & design supplement alternator powered loads such as “house batteries”. Or a written document that described the allowable auxiliary load ,,, good luck with that.

A Thread for You if you are interested to in what I was referencing above;


IMG_8910.jpeg


LOL ,,, That Depends ( Ya Might Be Overloaded with Only Factory Loads ) 😁.

Final Note; @HarryN designs quite conservatively from what I typically see out there. Example; He typically design battery banks that can provide twice the amps than needed to run say an inverter’s “Max Continuous Power”.

Not the typical Vehicle Manufacturers be like (how many amp can I have from my factory alternator for aux - Ram Depends maybe “none amps”).

I have seen many DIYers loads needed @ say 100amps & their batteries specs be capable of 100amps max continuous 😳. Designed to run @ 100%, thus in Engineering speak 0% Factor of Safety. Each to Their Own I Suppose.
 
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