[m38mike]

Has anyone ever tried using two chargers simultaneously to charge one pack? Would they charge the pack twice as fast if they were the same type of charger? What kinds of problems could be encountered doing this?

I'm looking at ways to speed up the charging process, but I'm limited by the capacity of existing chargers for DIY builders. So if you can't get a charger that's twice as powerful, how about two chargers of equal power?

[Bowser330]

Originally Posted by m38mike

Has anyone ever tried using two chargers simultaneously to charge one pack? Would they charge the pack twice as fast if they were the same type of charger? What kinds of problems could be encountered doing this?

I'm looking at ways to speed up the charging process, but I'm limited by the capacity of existing chargers for DIY builders. So if you can't get a charger that's twice as powerful, how about two chargers of equal power?

I think you can, you just need the chargers to be fully isolated and they can run in parallel.

There was a thread on this earlier did you try searching?

[dtbaker]

how much juice can you pull from the wall?
newer houses might have 200amp service, but MANY older homes only have 100amp panels to serve the entire house.

I am thinking that I am going to try to design in the capability to charge direct from PV. It would be limited to daytime charging, but have the advantage of direct DC-DC (skipping 2x inversion losses) and a fairly simple charge controller for the final voltage basically treating your EV as a rolling off-grid battery pack.

for instance, the newer panels from SunPower are 320+ watts nominal... each putting out pretty close to 55volts at 6amps under direct sun. with a dozen panels (3 strings of 4), you'd have 165 volts at up to 24amps... managed with a charge controller to your desired voltage and let it rip.

financial debate would be whether the dozen panels and charge controller would cost more or less than adequate electric service to your home, coal/nuke-fired electricity, and a monster AC charger.

[m38mike]

I did a search through the forums for parallel charging and came up with several folks who have done just that, charged with two to six chargers all running at the same time, all connected in parallel to the full pack. It seems that the big watch out in doing that is that the chargers need to be isolated. I never did read what would happen to the charger or the pack or the vehicle if they were not isolated, but that seems to be the consensus - make sure they are isolated.

They apparently don't need to be programmed to the same end voltage. If they are not, then it sounds like they simply quit charging when their individual max voltage is reached. So if another charger takes the voltage higher, that's not a problem.

There were several cases of using two or more different sized chargers in parallel. So it looks like it's a doable thing. Just make sure they are isolated.

[EVSource Mikey]

Ryan used two Elcon 14A chargers in the Sterling. I can ask for more specifics on wiring if you'd like.

[GizmoEV]

Originally Posted by m38mike

They apparently don't need to be programmed to the same end voltage. If they are not, then it sounds like they simply quit charging when their individual max voltage is reached. So if another charger takes the voltage higher, that's not a problem.

I use an NG1 and an NG3 to charge my pack. Together they pump about 55A into my 20 cell LFP pack. The other day I backed the voltage down on my NG1 from 69.3V to 69.0V. When I charged my pack with both chargers the NG1 did in fact turn off before the NG3 did. Each charger is on its own circuit. the NG1 draws about 12A at 120VAC and the NG3 draws about 15A at 240VAC. Just make sure that the charger with the higher voltage doesn't over charge your pack.

When the two chargers were set to the same end voltage they didn't seem to have any issues tapering the current back. It was almost as if the other charger wasn't there. I did observe that when nearing the end of charge when the chargers had cut back on the current that if I shut off one charger the other one would see the voltage drop and increase its current.

[m38mike]

I'm going to run a EMW 10000 and an Elcon 2000 together. They are isolated, so I'm hoping there should be no problems. The EMW will get 240vac and the Elcon will get 120vac.

I appreciate all the feedback and information about running pairs of chargers. It's given me confidence to try it with the ones I have.

[ricklearned]

I didn't see this thread until now. I am running two Meanwell power supplies in parallel. I am currently wiring up a programmable voltage meter I purchased from Light Objects to turn them off. Until that is connected I preset the ending voltage and I observed the current drop as the voltage approached that point. Then I shut off the charger manually.

[brainzel]

Sometimes I charge my pack with two Zivan NG3 in parallel.
The charge end voltage is set to the same value (157,5V) and everything is OK.
So I can push up to 30 Amps into the pack.