Renogy 12V 20A DC to DC On-Board Battery Charger for Flooded, Gel, AGM, and Lithium, Using Multi-Stage Charging in RVs, Commercial Vehicles, Boats, Yachts, 20A

Installed in my van to charge my Temgot 460ah battery off the alternator/battery. Easy to install, easy to set for your battery type. Lights stay on so a small draw but not significant. I got the 40amp version and it's great for my use. Went on an advanture with it on washboard roads for 3 hours- still performs like a champ.

ATTENTION: This is not the "smart" one. You will need to add a cable to a fuse or alternator that sends 12V only when the Ignition is on. Without that this device won't work.I used my fuse #8 in my 2000 Ford E350 which gives 12 V when putting the Ignition to ON. In combination with having it connected to my house battery I got the green LED which indicates everything works fine and it does charge 🙂

UPDATE: I would love to say this a great charger, however I have received two of them and neither of them worked correctly. The first one was DOA when I received it. It cost me $200 to have it installed, only to have my installer tell me it was not working correctly, and pull it out. I sent that back to Amazon, but was out the $200 installation fee.Stupidly, I bought a second one because I like the company. I again paid $200 to have this installed in my RV under the passenger seat where apparently it needs to go. This one worked, so I was happy with it. It worked well, in fact, for all of three days into my vacation, then I noticed on my battery monitor that there was no charge whatsoever coming from my alternator. On vacation, 2000 miles from home, I had to drive two hours to an RV place to have this unit taken out. Removal and reconnection of my old wiring cost me $220 this time. Now I am up to $620 in installation and removal fees.I drove the rest of my vacation with the straight alternator and was fine. When I returned I called Amazon and they agreed to take back the unit even though it was past the 30 days. They said they would charge a restocking fee but that the fee would be waived once they received the unit. They now refuse to refund the 45.00 restocking fee because the unit is not in re-sellable condition, to which I can only say, Of Course not!The long and short of it is that it cost me $665 to try to make this work and as much as I like the company, it doesn't. The units I got were defective and I would not order this again from them.

Anything that I say should not be mistaken for real knowledge so read at your own risk!😁this unit is what I needed to complete my not so usual project. The customer service from these guys is superb! Michael has been so helpful in guiding me through this one of a kind project. I presented my goal and he helped me achieve it. Thanks Bro!✌️ you are it!

I installed these units to charge the 2x 600ah battery bank(s) shown above.My instalation draws power from a 250 amp engine alternator.The charging units have primary input and output hookups of solid metal with machine screws to secure the wires. They also have 2x additional wire inputs. One wire input activates the unit, it will not charge untill voltage is applied to the "D+" terminal. This allows it to fuction as a battery isolator relay, whereby it wont charge untill its told to by the activation wire. It also has a second activation wire for a 50% power mode. This knocks the charging amperage down to 30 amps, and I highly reccomend wireing this lead to a toggle switch.I installed 2x units and found that a 250 amp alternator cannot power more than one of these at idle engine speed. At highway speed and higher rpm, I can run both units at 60 amps. but at night time with all lights on in the RV, I can only run one at 60 amps and the other at 50% power without overdrawing the alternator.The installation instructions indicate that they "may draw upto" 90 amps, but upon installation i havnt seen more than 65 amps.I installed 2 of these units which is kinda crazy, i did it by isolating two battery banks with a giant diode array, in the form of a battery isolator diode set installed "upside down" on the negative terminal side. but take note that a 250 amp alternator can barely power both of them when tacked ontop of the other electrical load for the RV.Installing one unit with a common 130-150 amp alternator it would be advised to install the amperage reduction function to avoid overtaxing the alternator at low engine rpm.The units have internal cooling cans that SUCK AIR from the electrical input side, and EXPEL AIR on the electrical output side. This information is only apparent AFTER installation, so ill include it here.2 gauge cable worked fine.to install the activation leads, unscrew the tiny screw above the wiring opening, insert the wire, then tighten the screw. This information is not included in the instructions so i include it here.Since you will probibly wire the activation lead to turn the unit on whenever the engine is running, advise installing an interupt switch for that lead, or a giant battery disconnect switch for the voltage input as I did.