Renogy12V 30A DC to DC Charger with MPPT & Multi-Stage Charging - Smart On-Board Battery Charger for Solar/Alternator Input - Charges Lithium, AGM, Gel, Flooded Batteries in RVs, Cars, Marine

This charger works great. Will charge my starter battery once battery bank is fully charged. Also switches to alternator charging the battery bank while driving. Easy to install directions are straight forward.

Well made unit that does what it's designed to do: control, optimize, and monitor DC to DC solar panel and alternator charging of your 12 volt house battery system. This all-in-one charging controller is easy to install for a person with a basic understanding of an off grid 12 volt electrical system; the included instruction are very clear and informative. The features via the optional BT-2 bluetooth module (highly recommend) are comprehensive and make monitoring your system status via your phone a must (and a pleasure). The unit also treats your battery right via multi stage charging that will extend the life of your battery.

This Renogy DC-DC Charger has been installed now for 10 months and has been very dependable. I did install it with the recommended AWG wiring for the length, using the recommended 40A fuse and I have had zero problems. The value is definitely there with this charger. The available App is actually pretty good but seems Renogy could add in some additional configuration options. The only reason I'm giving 4-stars for the mention of additional options in the App along with the manual could be slightly better as well. The manual is good and easy to understand but there are items I'd like to understand better and having to research it online is a bit frustrating.

Put this in a VW van along with a 100 amp hour Li Ion battery in the cabin. With the Bluetooth module you know all your stats on battery voltage and charging current. Used it with both alternator and solar. Keep in mind it can do 30 amp on alternator or 30amp solar but not at the same time. If both inputs are charging, neither will go above 15 amp. Like if you have 1 amp solar charging the max charge rate is 15amps alternator + 1 amp solar = 16amps. I unplug the solar when driving so I get full 30 amp charge.

I purchased the RENOGY 12V/24V 50A DC to DC Battery Charger with MPPT on 7/16. Unfortunately, the shipping was delayed multiple times, and after reaching out to Renogy customer support, they claimed it was Amazon’s issue, not theirs. After a frustrating delay, the charger finally arrived on 8/27.This week, I installed the charger, and based on my initial experience, I believe it to be unsafe. Electronics, in general, should not exceed operating temperatures of 176°F. However, during my first test, the charge controller reached 183°F before I had to shut it down. I contacted Renogy support again, and their suggestion was to unplug it, wait for an hour, and ensure proper ventilation. I followed their instructions, but the same overheating issue occurred.I reached out again and was asked to provide screenshots of the temperature and proof of proper mounting. After submitting the requested evidence, they promised that tech support would contact me within 24-48 hours. As of now, I am still waiting for a resolution.From my experience, it seems this product is not capable of safely handling 50A of current. It appears to lack adequate heat dissipation or efficient components necessary to operate at such levels. The charger is mounted in the engine bay as intended, and all tests were done with the truck hood open to allow maximum ventilation.I will update this review once I receive further information from Renogy’s tech support. Until then, I would recommend proceeding with caution if you’re considering this charger.Update: 9/13 Still Unsafe, Returned to AmazonAfter posting my initial review, I was able to get in touch with Renogy’s tech support. We went over everything—my wiring, mounting, and the specs of both my starter and house batteries. Renogy confirmed that everything was wired correctly and within spec. However, instead of offering a replacement, they insisted on bench testing the unit to verify the fault before taking further action. Given the hassle, I decided to simply return the unit to Amazon.If you read through the user manual, it clearly states that this charger is supposed to be thermally protected. It should decrease output current once it reaches 149°F and completely shut off if the temperature hits 176°F. In my case, the unit exceeded 183°F during testing without shutting off or reducing current, which is extremely concerning.This experience has left me questioning the safety of this product. I would recommend using it with extreme caution, as it seems the built-in thermal protection is not functioning as described.

I wouldn’t want to travel without it. We use this unit, 30a dc-dc w/ mppt, to keep our batteries topped off while traveling. We have an inverter, which allows us to run our fridge in AC mode while driving down the highway. This unit gives us 30a from the alternator, the fridge using 25a and 5 amp charging the batteries. When we arrive at our destination the food is cold and the batteries are usually topped off. We also hook up a Renogy portable 200w panel and a 100w panel. These are connected in parallel, as this unit can’t handle more than 25v in PV mode. I run two 6awg wires to the PV input with Anderson connectors on each one for my portable panels. I usually get around 220-270w of power from this unit, which competes with my 510w of roof mounted panels until mid day. Also note, if you use this unit with panels and alternator, you will receive a max of 15a from the panels and 15a from the alternator. That’s just the way the unit works. If mine even fails, I will replace it immediately with the same unit. I’ve been using this setup for two years now and took a trip to Alaska and back, traveling almost every day. I’m very pleased!

So I have had this about 2 years and there has been no issues with this and my batteries or truck. This will provide 30 amps to lithium batteries, and pulls about 40 amps from the truck to get that power. I do use the solar side with some moveable panels when I need it, and it has helped keep the truck topped off when connected. I liked it so much when I sold my last rv I removed it and installed it in my new one.