It keeps my batteries in an optimal charge state on my GMC Sierra Duramax

I am happy with the slow charge because fast charging can cause some permanent capacity loss for lead acid batteries.

There is an internal fan that comes on when charging at higher current levels, the charger can get somewhat warm when working hard

There is an internal fan that comes on when charging at higher current levels, the charger can get somewhat warm when working hard

Also price is expensive without fast charge for emergency needs.

I did a trickle charge on the old battery and a power surge/interruption killed the Noco G3500 charger

Once completed, it will start a slow charging cycle to restore the battery to 100% (or as close as it can get to that)

In my opinion this charge is well worth the money I have only had it for a month and its been great

That said, some form of a 'safe' charge mode would be nice on this unit and would make it a well-rounded charger

Works great, really keeps my Optima charged up.

Upon connection the Optima 400 started analyzing the battery and later started a trickle charge/drain cycle to decrystalize the cells

Which is a problem because that system wont fully charge an Optima battery correctly and eventually the battery will fail due to improper charging

Just be aware it is not a fast charging process in the least

Device performed as stated, it took eight hours from totally dead, full charge

Well my battery holds a charge again no problem so it definitely worked!

Only drawback is 5 LED lights tell 0%, 25%, 50% 75% and 100% charged

Works well, just slow charging

Turns out that it was good as well but only about 40% charged.

Works great - charges my batteries as advertised

Keeps my Optima red top charged and maintained while my classic sits in the cold garage

I'm doing it for the first time this morning, topping off the charge on a pair of new batteries just arrived from Amazon

Nice slow trickle charge.

High quality product from Optima, charges and services batteries like its

It works great and charges quickly.

100%).- Very good charge time: 9-16 hrs at 3.5-4A for weak batteries below 75%, and 12-30hrs for deeply discharged below 50%.

it does get warm if charging in high amperage

What I like about it is that it starts charging at high current and slows down as battery gets charged

The charger comes with a nice set of clamps as well as a charging pigtail commonly used by other brands of battery maintainers

This says my red top is fully charged but they are not

Nice slow trickle charge.

This Optima specialized battery charger works great for keeping your blue top Optima batteries conditioned and charged

However the battery was so dead before it quickly lost some charge so i bought my own

Works well, just slow charging

This unit has never failed me in keeping all of them in top charge condition.

Well my battery holds a charge again no problem so it definitely worked!

works perfectly out of the box and have charged four different batteries ( 3 Optima and 1 lead acid).

Also used it to charge a wet cell, don't look for a rapid charge for a low battery.

I got ahold of Optima after obtaining a receipt and Optima sent out a new charger out at no charge- free shipping and pick up of the defective charger from my home location

Optima wants you to select a battery type every-time you power up the charger, but if no selection is made after 10 minutes, it will automatically default to a safe charging mode.2

Very smart charging system that works really well.

That includes time spent in soft-ramped conditioning mode, for the final 10-15% of full charge.- Smarter than ordinary smart: This unit has separate setting for the following battery types - High Performance AGM (Starting and Deep Cycle) as well as Regular AGM & Ordinary Flooded types (Motorcycle and Automotive/Marine), and it dynamically runs them through 6 stages of charging, on an as needed basis: Analyze, a soft-ramped mode for batteries deeply discharged below 50%, Regular Charge, Conditioning Top-off charge, maintenance Float Charge, and a once per 30 days refresh lasting 3 hrs after which it switches back to maintenance mode

It will put an intelligent charge to a battery that many other chargers will not charge (or not charge correctly), and save you batteries as a result

I am happy with the slow charge because fast charging can cause some permanent capacity loss for lead acid batteries.

I was tired of fooling around with my old charger that was 10 plus years old, with these AGM batteries its important that the proper charging protocols are taken and with this

After the last cold spell here in ohio, and likely affected by insufficient charge, starting the vehicle revealed a sluggish start

Monitors air temperature to provide the perfect charge.

I like this charger it maintains and charges very good for the cylindrical battery

I even brought my car to my dealer and they confirmed the battery had a solid charge

It is small, well designed, and has many useful charging features such as providing a pre-charge status and four modes of battery charging.

I wish this charger had a 10A rapid charge mode ... besides being significantly faster that would enable you to do things like unhook the negative lead in a car with a dead battery, and charge it for 30-60 mins in order to start it

Only this don’t have fast charge to start the engine

Not what it's all cracked up to be, brand new unit doesn't shut off when battery fully charged and unit get hot when charging yellow top battery.

Work great charge a complete dead optima battery purchased in 2001

So with this new charger I can keep my Yellow tops fully charged and happy

(They were fresh and reasonably well charged on arrival.

Not as fast charging as I hoped for but will fully charge a battery unlike most chargers

The other thing is that it uses software to run a battery through the most efficient charge cycle after it analyzes the battery status

We hooked up this charger and it immediately went into the analyze mode, began charging and once charged, reverted back to monitoring the charge.

Bad A$$.Love

The charger worked as it should for the first couple of charges, but then all of a sudden it would get stuck in 'charging' mode indefinitely no matter how long the charger was left connected to various batteries, never advancing to maintenance mode on the LCD display.

Depressing as it is a sealed battery that shouldn’t vent and prior to now has never had any issues

After a couple failed battery charger purchases, the Optima performance maintainer works as it should