diy solar

diy solar

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

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;


View attachment 216131


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

Currently I'm running 6x dc dc converters from 24v to 12v and 24v to 48v. 3kw total, well under the 270a/24v 100% duty rated industrial 50dn alternator. Originally when setting up it had a 12v regulator setup to run 12v FLA 8d batteries. They make the 50dn in 12v and 24v so I assumed it's 12v as plate was scratched off. I used a wakespeed ws500 to charge my 12v system and it couldn't always keep the voltage down and would spike then shutdown. Eventually frying both battery bms and a bunch of 12v stuff.

Currently my 50dn alternator doesn't always work, the field wire is damaged. I have a 2nd one but haven't got around to installing as it's oil cooled and over 100lbs. So I'm using 1 or 2 DC converters while driving and on the 70a/24v chassis alternator. I combined the 50dn with the chassis alt all to the chassis batteries to help absorb any dc spikes, set the 50dn voltage higher than the smaller one so it overpowers and handles all the load. When running all 3kw converters my voltage doesn't drop. 1v regardless if idling or full throttle but now with just the small one I can only run 1000w or so and more if on freeway. I can watch the voltage drop and pickup depending on RPM and load
 
Currently I'm running 6x dc dc converters from 24v to 12v and 24v to 48v. 3kw total, well under the 270a/24v 100% duty rated industrial 50dn alternator. Originally when setting up it had a 12v regulator setup to run 12v FLA 8d batteries. They make the 50dn in 12v and 24v so I assumed it's 12v as plate was scratched off. I used a wakespeed ws500 to charge my 12v system and it couldn't always keep the voltage down and would spike then shutdown. Eventually frying both battery bms and a bunch of 12v stuff.

Currently my 50dn alternator doesn't always work, the field wire is damaged. I have a 2nd one but haven't got around to installing as it's oil cooled and over 100lbs. So I'm using 1 or 2 DC converters while driving and on the 70a/24v chassis alternator. I combined the 50dn with the chassis alt all to the chassis batteries to help absorb any dc spikes, set the 50dn voltage higher than the smaller one so it overpowers and handles all the load. When running all 3kw converters my voltage doesn't drop. 1v regardless if idling or full throttle but now with just the small one I can only run 1000w or so and more if on freeway. I can watch the voltage drop and pickup depending on RPM and load

I’m a bit confused here. You obviously have experience, but I am not clear what you are against.

Are you just against charging from a factory alternator via an inverter ? It is Dangerous ?

Reading the above, sounds like you fried a bunch of stuff without an inverter being in the mix ?
 
I’m a bit confused here. You obviously have experience, but I am not clear what you are against.

Are you just against charging from a factory alternator via an inverter ? It is Dangerous ?

Reading the above, sounds like you fried a bunch of stuff without an inverter being in the mix ?
I'm against using an inverter on a starter battery or any other massive load that turns on/off instantly, or one's that don't have voltage protection. Dumping 100a instantly is going to cause issues. Inverters have huge capacitors that need charged and they also dump quickly when off. Now lead acid start batteries help this but if the van only has 1 start battery it's not going to help much. For example I have 4 massive start batteries.

The only high power device in a normal vehicle is the starter and this isn't running when the alternator is running. Even vehicles with large fans will stagger start/stop the fans to minimize power dump.
 
I'm against using an inverter on a starter battery or any other massive load that turns on/off instantly, or one's that don't have voltage protection. Dumping 100a instantly is going to cause issues. Inverters have huge capacitors that need charged and they also dump quickly when off. Now lead acid start batteries help this but if the van only has 1 start battery it's not going to help much. For example I have 4 massive start batteries.

The only high power device in a normal vehicle is the starter and this isn't running when the alternator is running. Even vehicles with large fans will stagger start/stop the fans to minimize power dump.

That clarified your opinion & fair enough ,,, thanks @justinm001

An Inverter or Any Other Massive Load

I guess another way of putting it would be “Any Massive Load”

I wonder if a 500W or 750W inverter would work ok?

Technically my Kisae 1250 can provide 14.7vdc @ 50 Amps = 735W / efficiency 90% = 817W
 
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@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.
 
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;


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.

Thanks -- that was the chart I was looking for for typical loads.
 
@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.
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
 
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Just looked that up ,,, this one ?


View attachment 215980


42v “output” voltage ,,, that works for you ?
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.
 
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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!!!😎
 
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.
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.
 
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.
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.
 
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!!!😎
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!​
 
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