Atem Power 12v DC to DC 50a Battery Charger

Excellent product and fast delivery even to outback Queensland. Thanks

Doesn’t work with smart alternator – Just doesn’t work. Replaced my existing Redarc dc dc when i changed to a lithium battery as Atem stated that it had the lithium charge algorithm and was compatible with modern smart alternators, well it isn’t and just doesn’t work. MPTT works with the solar panel but will not charge from the start battery properly. I will be buying the upgrade Redarc charger compatible with my lithium battery. Save your money and avoid this one.

Seriously flawed design – Don't waste your money on this brand of DC DC charger. They have several serious design flaws. The MPPT solar charger section will not start to charge reliably in lower light conditions where other brands such as CTEK, Renogy, Enerdrive, Victron and Redarc operate just fine. The 12 volt/vehicle driven DC DC charger part of this unit is voltage sensitive and does not work properly with a SMART alternator, which almost all modern vehicles possess. For instance, all charging ceases at 12.5 volts regardless of the IGNITION enable function. SMART alternators often completely stop charging for a period and allow the vehicle battery to fall below 12.5 volts. This charger then cuts out while you are driving. At voltages between 12.5 and about 13.8v, the voltage zone where a SMART alternator operates most of the time, the rated current output of this DC DC charger derates so you don't get the full advertised output charge current. These observations are for the Lithium battery setting. I did not check if the same problems were evident for AGM. Above about 13.8V, it charges fine so the vehicle driven ATEM DC DC charger may work OK in an older vehicle with fixed voltage alternator. I do not recommend the ATEM range of DC DC chargers. You can do much better.

Absolute junk – Supposed to be 50amp but comes hard wired with cables that are rated to 30ampnif your lucky. Shuts down every few days so when at work I come home a few days later to find it has locked up and not charging off solar and my food spoiled

Has limited use – This review is about the Atem Power 12V 50A DC to DC Dual battery charger with solar input. It is sold on eBay and other sites. People purchasing this item should be aware that for this item to charge a second battery e.g. in a caravan or camper, it HAS to be always connected to the main vehicle battery. The solar input will not work (charge) independently if you disconnect your caravan or camper from your car and think that your solar panels will charge your 'house' battery via the Atem charger whilst you free camp or drive around in your car.

It most probably works in a motorhome or boat where your main and second battery are never separated.

I installed this charger in my caravan only to discover it would not charge via the solar input. The seller has offered a refund which I accepted but I have had to pay $15 return postage. Additionally I have paid $25 for special fuses/circuit breakers which are required in the installation instructions but which I now do not need.