MotoMaster Nautilus Battery Charger,15/10/2A

Man, oh man.. I’ve used a lot of chargers. I even bought the updated version only to have it stolen. Anyway… This thing has provided me a decade of dependable service. I ended up learning that even when applying 12 v to the posts under the hood., most of my cars have built in multi stage chargers lol so I’m basically just powering that. It’s great for that. Responds relatively quick almost as if it was a power supply. Example; if I am trying to charge the battery after a short drive and doing some mild obd scan or flashing a single module, 15a is juuuust enough, at 14.7v to allow it to work. It’ll taper down to say.. 5a with key on and fuel pump primed, etc. after 3-4min so I can scan or do whatever, then once I’m ready to flash it’ll ramp up to 15a in 1-3sec and stay there. It’ll fully charge a 110ah battery in roughly c-10hrs. It’s hard to say how much capacity these huge things really have as some 90ah batteries have longer “reserve capacity” than my larger 110-140ah ones. Anyway.. 5-8 hrs for a 50% discharg battery at 10a for 80ah and lower, or 15a and 8-10hrs to charge an h7-h8 or h9 truck battery or bmw battery. It’s similar to the Schneider electric version with the same size. I’m yet to verify if it’s the same but it’s tested by intertek.

I own this for about 5 years and it's the best.

Bought this a few years ago to charge my 4 6v lead acid batteries wired in series and parallel, and it's still going strong.

Failed after occasional and extremely light usage at the 2 year mark. Was trickle charging a garden tractor battery at 2A current. Disassembled to troubleshoot and found blown power transistor and fuse. Printed circuit soldering was clearly done by unskilled labour. Very poor...

I’ve had this for three years. It is a capable charger but not “automatic” by any means... It will hang in its “acceptance” phase indefinitely at 15 volts (while displaying 14.8) displaying 90% charge. Works fine for bulk charging at 2/10/15 amps, regulating the voltage to put out the selected amps, but you can’t walk away from it or leave it overnight and expect it to transition into “float” mode. 15 volts is simply too high for an “acceptance” voltage and will quickly boil off a flooded battery, and will damage a maintenance-free, AGM, or Gell battery. There are much better options for the money.