AC200Max - Not able to charge from van using 12V/24V to 56V 20A 1120W DC DC Step Up Converter Voltage Regulator Charger

I’m trying to charge my AC200Max using [12V/24V to 56V 20A 1120W DC DC Step Up Converter Voltage Regulator Charger - CN] and/or 1. 12V/24V to 56V 10A 560W DC DC Step Up Converter Voltage Regulator Charger

The Bluetti charging display keeps changing from 830watts to a 0watts while the engine is idling.

I measured a 56VDC output with 12vdc input.
I tried the setting to both PV and Car/Other … no luck
Are there any work arounds?
I’m trying to charge the Bluetti as close as possible to the maximum of 1400watts, while I’m driving.
PS - I’m also using the DC Enhancer for the Adapter Input port.
Thank you for your help in advance

My first thought is “Is your wiring heavy enough to carry the amperage load” and is the voltage dropping off too much under load due to insufficient wire size which is cycling the step up converter.

I am using four gauge jumper cable wire. I cut the alligator clips off the jumper cables. I’m using that wire it’s about 15 feet long from the front to the back.

You are probably pulling in the neighborhood of 75 to 80 amps. You want the shortest wires from the battery to your step up converter and then the longer run and thinner ga. wiring can be from the step up converter to the load. I am showing 1 ga wire if you are talking about a 15’ run at 12 VDC from the battery to the step up converter. If you made some temporary very short run cable and had improved results this would indicate your wire size is insufficient.

First thing I’d check is the van’s alternator output. What the maximum amperage output for your alternator? If you’re pulling anything like 75 to 80 amps, you had better be running an alternator well north of
150 amps. And that’s not including the very important cabling advice from the moderator. A lot of that battery charger cable stuff is copper-clad aluminum. My opinion for high voltage high amperage automotive power transmission is to to use pure copper. It’s expensive, but it’s still a lot cheaper than replacing alternators (which you might have to do anyway), electrical systems, or dealing with fire hazards.

I changed to factory alternator (75amps output), to a heavy duty alternator (135 amps output).
I have a 12vdc switch-box that has 4 toggle switches that turn on 3 separate 12vdc outputs, that turn on and off the 3 voltage step up regulators, (along with a switch that passes the 12vdc battery source to the back of the van).
So when I just add in the 56vdc/20amp regulator by itself, it does not work on the Bluetti AC200Max 10 - 145 DC 15A (PV/Car) Input

I also tried the [56vdc/10amp regulator] by itself, it does not work on the Bluetti AC200Max 10 - 145 DC 15A (PV/Car) Input
I also have a DC-DC 12V Step Up to 36V 20A Car Power Supply Converter Regulator that I use to charge my portable heat pump (EcoFlow Wave 2)
The input on the Bluetti AC200Max’s display just flashes 830 Watts and then 000 Watts, using the 56vdc/20amp regulator
Is there any chance I can call you because texting can take weeks instead of a phone call that can take 5 minutes?
My name is Louie and my phone # is 704-254-1588 , text me before calling so I will pick up the phone to defeat any telemarketers.
Thank You

Have you got PV selected as the input setting?

Yes I had the setting on “PV”

Can you send me a link for the wire going from the main battery to back battery (15Ft)
wire type and size I should purchase?
Thank You

I don’t have a link, but you would be better off locating the step up converter close to the battery and then running the stepped up voltage back to your Bluetti. You can use much thinner wire with the stepped up voltage over the longer runs. I would test the system temporarily connecting the components in the desired manner before you mount anything so you can modify the install if needed.

Hello Scott:
Could the wire (4awg CCA-type Jumper Cables 15’) I’m using be the problem?

could be if they are just clamps or the wire is not decent quality.

I think it’s time to get back to basics. First of all, do you have a “smart” alternator? I have an older truck (2001) that has a maximum 150 amps rating when the alternator is at maximum output. At idle, it generates around 100A. After around 2015, car manufacturers started making “smart” alternators that control the amperage based on the car’s (van’s) electrical requirements. That means amperage can be all over the place. Second, you will never get more charging amperage than what is output from your alternator. If your alternator is putting out a maximum of 135A (12v) that’s a theoretical limit of 1620 watts (135A x 12v). You have to subtract from that your vehicle’s requirements, namely ignition, charging, sound system, air conditioning, fans, lights, etc., etc. The rule of thumb is that the vehicle AT IDLE (which will always be lower than the theoretical alternator maximum amperage) must allocate 50% of available amperage to the vehicle’s requirements. Sitting at a stoplight with your AC at full blast and your sound system cranked up, you might only have 40A available for charging, and that’s 40A x 12 = 480 watts.

CCA cable is not designed for heavy electrical loads for a long period of time. They’re designed for short bursts of a heavy load for a few seconds to jump a battery. I installed 2 AWG marine-grade pure copper conducting cables for the run from my starter battery to the truck bed. At the truck bed, the cables are connected to a Renogy DC to DC 40A charger, which, in turn, charge a 200AH LIFPO battery. From the 200AH battery, I can easily top off my Bluetti AC200 MAX and run a 5000 BTU AC window unit (Energy Star) all night.

I found an Auto Sound Installer that will cut the proper length of Pure Copper wire (and put terminal ends on them), so I can bench test this and see what happens. I plan on doing this sometime next week. I’ll let y’all know my results of the testing.
Thank You

Excellent! The professional custom audio technicians know how to manage 12v-48v DC vehicle wiring from A-Z. Let them know what you’re trying to do and I’m sure they’ll give you some good advice.