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

RV8R said:
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;

www.promasterforum.com

180 amp Alternator with amp clamp on output

www.promasterforum.com www.promasterforum.com

View attachment 216131


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.
Click to expand...

Thanks -- that was the chart I was looking for for typical loads.
 
HarryN said:
@justinm001

A more typical charge rate for use like this is 500 - 800 watts.

Just some examples - on a promaster, the radiator fan switches on / off 50 amps routinely, and air conditioner blowers similar amounts or more.

The Ford Transit has an engineered customer connection point built in to many of their vans ( unfortunately not all ) that is all set up. It turns on / off with the engine - with some built in timer delays and manages the situation so that if the starter battery voltage goes too low, it can disconnect it.

The Ford even has a shunt built into their power system to measure what is going on with current flow and the ECU that runs the alternator field current adjusts remarkably quickly to changes.

There is even a version with dual 250 amp alternators / dual starter batteries that can support 1500 watts ( absolute max ) for ambulance use , but DIY ers have pulled close to that as well.

@RV8R has a promaster with a DC - DC converter that he has turned down to I think 50 amps for charging his battery pack. Perhaps he will put up a graph of the thing running.

Sterling makes BTB chargers up to 120 amps @ 12 volt. Not sure if those have a soft start or not, but the older models that I played with did not - it was hard on / off.

Some people will add on an aux switch to run the inverter and turn them on at highway speeds if their van does not support some of the more advanced functions. 500 watts is not a big deal in a modern van with a HD alternator.
Click to expand...
Typically they have multiple radiator fans and they're multiple speeds. So even if it's 50a/600w max when they turn on they always start/stop on low then go med then high. AC generally too it's partially why we have digital thermostats now.

But with 50a or so it's not really an issue as the starter battery will absorb those loads. Different story with 150a and just a single start battery. A good example is trucks with snow plow prep packages as they'll have dual alternators and dual batteries so they can help handle the larger rush current. I believe dual alternators is much better suited for this over a single larger one as it's easier to regulate voltage and split the load dumping.
 
Hi @justinm001

I understand your concern of overloading any given alternator, with any given load ,,, not limited to inverters. I also understand you have fried equipment even without an inverter being present.

Further, I think it really depends upon the vehicle, the equipment, & the design. In short there are failures or worse fires when the designs are not right. Somewhere something is overlooked. Inverters are not evil per se, but they require understanding & should be respected for what they are. In short, they can be a “Big Deal” & especially in 12vdc battery supply.

We went years Promaster Vanning without an inverter. Recently, as we ditched out Honda 2200 generator from our van, we purchased a $65 500W inverter from an Automotive Store & it isn’t even pure. We use it to recharge my wife’s hand blender that is battery operated ,,, that is our only typical 120vac van use (& we have a 30amp shore power 6 circuit breaker 120vac panel system that we almost NEVER use).


Our AGMs are Rolls 250Ah 12v. We use to charge them via “battery combiner” a system I call “Direct Alternator Charging” from our 220a factory Promaster alternator. I designed this system under the typical use we had for years, & our use pattern changed forcing me to look at my design as we were deeper cycling our AGMs to lower & lower SOC on a system that by design required a high SOC to keep the current under 60amps. The design “worked” until it didn’t.

One morning, after less driving & more boondocking near Lake Shasta CA, I fired up the Promaster engine & “spiked current” over my max designed allowable self imposed limit of 80amps ( slow to blow fuse fail safe ). Why would I design a system around this 🤷‍♂️ ,,, In short “I am stubborn” ,,, Ego ,,, Whatever personality flaws I have “We don’t need no stinking DC2DC with AGMs”. Here is a screenshot of that Lake Shasta morning;

IMG_8920.png

So bumping on a 90amp spike & quickly dropping, my 80 amp fuse didn’t blow. I have a spare 100amp to swap out a burnt 80, but the real fix is that Honda generator we no longer pack & out shore power 120vac & converter / 55amp charger 🤪. So you can see where this is going.

As I sit there staring at my direct charging alternator system amperage coming into my design specs range, my Wife asks me due to our changing van use pattern, “How do we fix this”. Feeling defeated, I admit by spending $500 on a DC2DC Kisae 1250 so I can program the charge voltages & amps trailered to our alternator & Rolls AGMs. It was an admission of guilt & being wrong ,,, I can sugar coat it, but it came down the the Van working for Us or Us working for the Van.

So when we arrived home (my tail between my legs), I ordered & installed the Kisae 1250 & set it up ,,, Bulk / Absorption / Float & amperage limited to a Max of 50 amps ,,, User Programed for the AGMs. Here is a lower SOC engine startup charge screenshot;

IMG_8927.png


The bulk / absorption is set @ 14.7v ,,, the amps are set to 50a Max.

I do not believe this will typically tax my 220a factory alternator.



The above is why I am not interested in a typical AIO for my van. In the past they have been designed as portables that are charged @ home thru 120vac to battery voltages typically close to 48vdc. Very proprietary !!

I am strongly against Proprietary ,,, as much as practical. My Van has;

Rolls AGMs
Kisae 1250 DC2DC
Parallax Power Center 120vac converter/charger
Victron 712 Shunt
Blue Sea misc items ( switches / fuses / etc )

Here is another screenshot of the Kisae charging;

IMG_8924.png
 
Last edited:
RV8R said:
Just looked that up ,,, this one ?

www.pecron.ca

PECRON 500W Car Charger DC1242-500 for Cars, RVs, Trucks, etc.

PECRON 500W Car Charger DC1242-500 Except for the United States, if there is a customs clearance requirement in other countries or regions, the recipient needs to cooperate with the customs to handle the customs clearance. We are not responsible for the customs clearance affairs of the...
www.pecron.ca www.pecron.ca

View attachment 215980


42v “output” voltage ,,, that works for you ?
Click to expand...
SEE UPDATE BELOW!!!!


After watching the operation and performance of the Pecron 500w DC 1242-500 And weighing the pros and cons, extra features and price difference of the Ecoflow alternator charger vs the Pecron I canceled my order for the Ecoflow and ordered the Pecron for $134 no taxes after discount Compared to the Ecoflow that was $425 after discount and taxes. Couldn't justify the cost and need of the added features.
I can still monitor power output and battery voltage and other parameters from my D2M Ecoflow app.
It is a relatively new device and hope dependability and quality is up tp par. But saving $291 I feel it might be worth the risk. I could buy two more for other uses and vehicles and still be ahead.
 
Last edited:
UPDATE ON PECRON!!

Be aware this company is selling items that are out of stock without showing this.
They will charge your credit card immediately and not disclose item is out of stock. I found this out after 5 days of waiting. Their excuse was maybe available in stock sometime in June.
Website still show available and they have received complaints and notice this is false.
Do you really want to trust this company that has shown dishonesty and deception??
Much negativity concerning their customer service also. Except for the paid for good reviews.
Avoid Pecron if your smart!!!😎
 
Dave in AZ said:
Whaaaat? Thanks!! This does not show up on Victronenergy.com, nor on any of the dc dc pdf product charts they have. AND I went to the Victron booth at Overland Expo West, and THEY said they didn't make a 12 to 48v!
I think I like this better than the Pecron offering, just a bit more $, and I can boost to higher voltage.
Click to expand...
https://productimageserver.com/literature/ownersManual/103414OM.pdf check page 2 second table. Looks like its actually adjustable 60V output as per spec (which I trust) expect 380W under normal conditions. its going to be extra hot.
 
Note that Victron has the Orion TR which runs appliances and Orion TR Smart which charges batteries. They also have isolated and non-isolated versions, though it’s not clear they actually make all four flavors in every available voltage combination.

#WeDemandRigidlyDefinedAreasOfDoubtAndUncertainty.
 
Dave in AZ said:
Whaaaat? Thanks!! This does not show up on Victronenergy.com, nor on any of the dc dc pdf product charts they have. AND I went to the Victron booth at Overland Expo West, and THEY said they didn't make a 12 to 48v!
I think I like this better than the Pecron offering, just a bit more $, and I can boost to higher voltage.
Click to expand...
I needed one for my mobile build and found this one. They did have it listed in their pdf on the website it’s like the last Orion listed on the spec sheet. But I just rechecked and I don’t think they make them anymore? Or it’s just buried on their website somewhere? I’ve always found it alittle frustrating trying to navigate their website for info. But all the same, you’re welcome!
 
have any of you considered a mechman alternator? these are alternators used in ambulances and vehicles with huge DC loads, i know for a fact they make models from 180 up to a whopping350 amps at 14.7 volts. If you basic load from your vehicle is say 100 amps that leaves 250 on the table to charge batteries that are powering a inverter to then charge your power bank or whatever 48 volt bank you want to charge.
 
MrNatural22 said:
UPDATE ON PECRON!!

Be aware this company is selling items that are out of stock without showing this.
They will charge your credit card immediately and not disclose item is out of stock. I found this out after 5 days of waiting. Their excuse was maybe available in stock sometime in June.
Website still show available and they have received complaints and notice this is false.
Do you really want to trust this company that has shown dishonesty and deception??
Much negativity concerning their customer service also. Except for the paid for good reviews.
Avoid Pecron if your smart!!!😎
Click to expand...
Didn't you receive their notification email? I received this email on the 24th of May.
Similar to this one:

A note for 500W car charger​
We are very sorry! 500W car chargers are very popular. Orders placed in mid-May need to be queued for delivery. They are expected to arrive at the CA warehouse next week and will be shipped one after another.
Orders starting from May 26th need to wait for the third batch of 500W car chargers to arrive at the warehouse before delivery. The third batch is expected to arrive at the warehouse at the end of June.

(Sorry that due to system reasons, the notification email we automatically sent to customers seems to have failed to be sent, apologize!)
Therefore, we will still maintain the lowest promotional price during this period, and we will end the promotional price after the normal inventory is restored. Thank you so much for your support!​
 
pollenface said:
Use the link i provided, i only know them as "1200w boost converter"

Punch that into Google, you'll get about 100 results of the same thing
Click to expand...
Ahh, I didn't see you made the words a link, didn't see the link, thanks!
So, that device at 12v input will only do 20A, 240W total. Not a great amount of power to pull off alternator. But it's very cheap. However, reading the almost nonsensical instructions provided, I basically wouldn't trust hooking this to my car's electrical system, battery/alternator. I'm gonna want something a bit more tested and reliable than an exposed circuit board with uninterpretable Chinese-English instructions... one bad hickup when attached to my car's electrical and I fry ECU and chips that I can't replace these days, not gonna trust that thing...
 
Well I have used my 12v system to charge my 48v batteries for my house's 48v system.

The way I did it was using a socket I had purchased at the hardware store to allow me to plug my chargeverter 2 into the 12v systems inverter :)

It didn't like it but it ran it. Its a 12v 3kw inverter and it ran the chargeverter 2. Was something I wanted to see if it would work and it did.

Horribly inefficient to say the least but it worked...
 
pollenface said:
I've seen that a few times in other people's cars.

Inefficient but gets the job done
Click to expand...
That's what I'm using right now, my Tacoma 400W inverter. But it puts out a Modified Sine Wave which power ststions with an onboard charger won't recognize or use. So I have to plug in a 480W variable power supply to convert the MSW 120V to 50v dc, and feed that into the solar mppt on power station. I'm using a Drok power supply from Amazon, it's not reliable and is just one small step above the one pollenface referenced... mine has a cover, that's about it more. Instructions to set constant amps and volts all in Chinese-englush, can't be understood. Fuse already burned out twice, at 7A and 55V, 385W, well below its rated 60v and 8A. So I totally dont trust it, which is why I'm looking for a tested, reputable 12>>48v converter. ;)

I ordered the 500W Pecron.
 
RobertoJJJ said:
Didn't you receive their notification email? I received this email on the 24th of May.
Similar to this one:

​
​
A note for 500W car charger​

​
​
We are very sorry! 500W car chargers are very popular. Orders placed in mid-May need to be queued for delivery. They are expected to arrive at the CA warehouse next week and will be shipped one after another.
Orders starting from May 26th need to wait for the third batch of 500W car chargers to arrive at the warehouse before delivery. The third batch is expected to arrive at the warehouse at the end of June.

(Sorry that due to system reasons, the notification email we automatically sent to customers seems to have failed to be sent, apologize!)
Therefore, we will still maintain the lowest promotional price during this period, and we will end the promotional price after the normal inventory is restored. Thank you so much for your support!​
Click to expand...
That was done AFTER canceled orders, several complaints were lodged to Pecron and the paid youtube hawkers. buyers only found out after watching no progress on the shipping and complaining. Then they changed the web site to denote preorder. This was not on the web site previously and ZERO notices were sent out to those expecting the productTHEN they grab you by saying buy now for promotional price!! Then raising the price if you don't act now!! LOL
Yep some fools fall for that all the time.

You can toss your cash where you like but good luck if you ever need customer service or warranty problems You will be greatly disappointed.
Pecron is not an honest company. And the biased YouTube paid reviewers are pushing this inferior product.

I went with Victron instead. Better all around and never had issues with a reputable company.
 
Last edited:
MrNatural22 said:
That was done AFTER canceled orders, several complaints were lodged to Pecron and the paid youtube hawkers. buyers only found out after watching no progress on the shipping and complaining. Then they changed the web site to denote preorder. This was not on the web site previously and ZERO notices were sent out to those expecting the productTHEN they grab you by saying buy now for promotional price!! Then raising the price if you don't act now!! LOL
Yep some fools fall for that all the time.

You can toss your cash where you like but good luck if you ever need customer service or warranty problems You will be greatly disappointed.
Pecron is not an honest company. And the biased YouTube paid reviewers are pushing this inferior product.

I went with Victron instead. Better all around and never had issues with a reputable company.
Click to expand...
I received this email on the 24th, they seem to be out of stock since the 23rd, the email I received was not delayed, in fact I have owned Pecron products since last year and so far the service I have received has been very good, Anyway, I hope we all have the best experience, I loved bluetti before but the high prices put me off!
 
Sterling makes this 12v to 48v b2b controller. 1500w, Powerful with great reviews.

sterling-power.com

12V/24V to 48V Battery to Battery Charger w/ reverse charging feature

12V / 24V to 48V DC to DC Chargers 115A input and 26A output model (1600W input and 1500W output) - E-Marking | BB1248120 5 Years Warranty - From 1st November 2024 If you need 24V input and 48V - click here BB124865 - a smaller / lower powered derivative of the BB1248120. 12V and 24V input to...
sterling-power.com sterling-power.com
 
chicagoandy said:
Sterling makes this 12v to 48v b2b controller. 1500w, Powerful with great reviews.

sterling-power.com

12V/24V to 48V Battery to Battery Charger w/ reverse charging feature

12V / 24V to 48V DC to DC Chargers 115A input and 26A output model (1600W input and 1500W output) - E-Marking | BB1248120 5 Years Warranty - From 1st November 2024 If you need 24V input and 48V - click here BB124865 - a smaller / lower powered derivative of the BB1248120. 12V and 24V input to...
sterling-power.com sterling-power.com
Click to expand...
Nice. Wow, $709 though. Lotta coin for that 1500W. Makes sense, Victron is $200 for 400W, it would be $800 for them.
 
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