NOCO Genius Waterproof Smart On-Board Battery Chargers

NOCO Genius Waterproof Smart On-Board Battery Chargers are group of lead acid battery chargers. They come in several versions regarding charging current (4A and 10A) and number of battery banks that can be charged at the same time (1, 2, 3, or 4 battery banks). Also, they have very important safety features like reverse polarity protection, sparks prevention, prevention of overcharging, overcurrent, open-circuits, short-circuits and overheating.

gen 4 bank 40a 1

NOCO Genius are on-board battery chargers for charging and maintaining 12 V marine starter, dual purpose or deep cycle batteries regardless of the type of the battery (Flooded, Gel Cell, AGM). They charge at either 4 A per bank (GEN Mini-Series) or 10 A per bank (GEN Series).

They are designed to be waterproof, shock and vibration resistant and to be mounted directly onto a variety of applications, like boat, internal combustion generator, electric vehicle, industrial equipment etc.

NOCO Genius chargers monitor battery status to enable safe, fast and efficient charging. Note that their charging currents are limited to 4 and 10 A, hence, the speed of charging also depends on the capacity of the battery pack and discharge level. These battery chargers can be left connected to the batteries all the times to provide maintenance charging. However, it is good practice to check the battery periodically.

For example, if you have starting and deep cycle batteries on the boat (with common ground line, but separate live/positive lines/wires), and you have the option to plug the boat into the power outlet in the port, having two bank charger, permanently connected to the batteries, will charge the batteries as soon as the boat is connected to the power outlet and will maintain the batteries while the boat is at rest, even for weeks. Similarly, any other lead acid battery, regardless of application, can be charged and maintained using these chargers - just remember maximum line currents (4 A and 10 A).

Chargers are very efficient, with efficiency around 90%. Nonetheless, they do dissipate heat and are cooled via natural convection. So, if it is possible, place the units in well ventilated area, preferably in vertical position, with air passing around the chargers. If the units get very warm/hot, check the status of your battery/batteries and if required, turn the chargers off. Sprinkling the charger with water to cool it down is possible, but not recommended - really not recommended! :) Water and electricity don't mix up very well!!!

Chargers are fully sealed and waterproof design rated at IP68.

gen 1 bank 10a 150Note: IP stands for the 'International Protection' marking, a standard drawn up by the International Electrotechnical Commission (IEC). First digit (6) means 'Protection from contact with harmful dust', while second digit (8) means 'Protected from immersion in water with a depth of more than 1 meter for longer than 30 minutes.' Manufacturer must specify exact depth and time - we couldn't find it on official NOCO site, but rest assure that these chargers can operate submerged 1m or more, for more than 30 minutes.

NOCO Genius chargers offer several very important safety features like:

- spark-proof technology and reverse polarity protection, very important for preventing fire, damage and injuries.

- provide full-charge output even with low-line voltages, with input voltages varying between 70 and 130 V and 50 to 60 Hz.

- built-in battery desulfator to recover worn-out batteries. Interesting feature which can bring old batteries to life, however, note that such batteries are never 100% reliable as new ones.

- chargers are saltwater-tested to combat corrosion and safe operation in wet conditions.

gen 2 bank 20a 150NOCO Genius chargers use several steps when charging the batteries:

- analyze and diagnose - in this phase, charger checks the battery’s initial condition, including voltage, state-
of-charge and health, to determine the status of the battery before charging.

- recovery - in this phase, if required, charger initializes the recovery desulfation process for deeply discharged or sulfated batteries by pulsing small amounts of current.

- initialize - in this phase, charger starts to 'gently' charge the battery, testing its behavior.

- bulk charge - in this phase, charger starts the bulk charging process based on the condition of the battery and tries to charge the battery to its 80% capacity.

- absorption charge brings the charge level to 90% by delivering small amounts of current to limits battery gassing.

- optimization - in this phase, charger finalizes the charging process and brings the battery to its maximum capacity.

- maintenance - in this phase, charger continuously monitors the battery to determine when a maintenance charge should be initiated. The cycle between Optimization and Maintenance is repeated indefinitely to keep the battery at full charge.

Features and Specifications of NOCO GEN Mini Battery Chargers

Features and specifications of NOCO GEN Mini battery chargers are given in the following table:

Battery Charger NOCO GENM1 NOCO GENM2 NOCO GENM3
Photo gen mini 1 bank 4a 150 gen mini 2 bank 8a 150 gen mini 3 bank 12a 150
Input Voltage AC 110-120 V, 50-60 Hz 110-120 V, 50-60 Hz  110-120 V, 50-60 Hz 
Working Voltage AC 70-130 V, 50-60 Hz 70-130 V, 50-60 Hz  70-130 V, 50-60 Hz 
Nominal Voltage DC 12 V 12 V  12 V 
Charging Voltage 14.4 V 14.4 V  14.4 V 
Efficiency ~90% ~90%  ~90% 
Charging Battery Size 20-120 Ah  20-120 Ah 20-120 Ah 
Maintaining Battery Size All sizes All sizes All sizes 
Battery Banks 1 2 3
Dimensions 6.6 x 3.8 x 2.2 inches
~16.8 x 9.7 x 5.6 cm
7.9 x 5.5 x 2.2 inches
~20 x 14 x 5.6 cm
 8.9 x 6.9 x 2.6 inches
~22.6 x 17.5 x 6.6 cm
Weight 3.3 pounds
~1.5 kg
 5.8 pounds
~2.6 kg
8.6 pounds
~3.9 kg
Cables AC - 72 inches (~183 cm)
DC - 78 inches (~198 cm)
AC - 72 inches (~183 cm)
DC - 78 inches (~198 cm)
AC - 72 inches (~183 cm)
DC - 78 inches (~198 cm)
Amazon Link NOCO GENM1 NOCO GENM2 NOCO GENM3

Note: Amazon links in the table are affiliate links.

noco genm3 cablesNOCO Genius GEN Mini Series chargers charge lead acid batteries with 4 Amp current per bank. They operate at any voltage between 70 an 130 V and 50 to 60 Hz, with minimum ripple current (less than 2%) - mains power, diesel or gas generators or anything similar.

For optimum operation, however, stable 110-120 V input voltage is preferred.

Cables are quite long, with AC cables being 72 inches (~183 cm) long and DC cables being 78 inches (~193 cm) long.

These chargers can be used to charge the batteries anywhere from 20 to 120 Ah and can maintain lead acid batteries of any size.

NOCO Genius GEN Mini Series chargers also differ in size and price - the more DC lines, the larger the price and also the price. For best offers, feel free to check Amazon links in the table above.

Features and Specifications of NOCO GEN Battery Chargers

Unlike NOCO GEN Mini Series, which provides 4 Amps per bank, NOCO GEN Series provide 10 Amps per bank, enabling faster charging. Also, they are slightly larger, heavier and tend to cost more, but they are all built to last, and in the end, they are very cost-effective chargers.

Features and specifications of NOCO GEN battery chargers are given in the following table:

Battery Charger NOCO GEN1 NOCO GEN2 NOCO GEN3 NOCO GEN4
Photo gen 1 bank 10a 150 gen 2 bank 20a 150  gen 3 bank 30a 150  gen 4 bank 40a 150 
Input Voltage AC 110-120 V, 50-60 Hz  110-120 V, 50-60 Hz  110-120 V, 50-60 Hz  110-120 V, 50-60 Hz 
Working Voltage AC  70-130 V, 50-60 Hz 70-130 V, 50-60 Hz  70-130 V, 50-60 Hz  70-130 V, 50-60 Hz 
Nominal Voltage DC  12 V 12 V  12 V  12 V 
Charging Voltage  14.4 V 14.4 V  14.4 V  14.4 V 
Efficiency ~90%  ~90%  ~90%  ~90% 
Charging Battery Size 25-230Ah  25-230Ah  25-230Ah  25-230Ah 
Maintaining Battery Size All sizes  All sizes  All sizes  All sizes 
Battery Banks 1 2 3 4
Dimensions  7 x 6 x 3.3 inches
~17.8 x 15.2 x 8.4 cm
8.5 x 6.5 x 3.3 inches
~21.6 x 16.5 x 8.4 cm
11.5 x 8.5 x 3.25 inches 
~29.2 x 21.6 x 8.3 cm
11.5 x 8.5 x 3.25 inches 
~29.2 x 21.6 x 8.3 cm
Weight 6.4 pounds
~2.9 kg
 8.7 pounds
~3.95 kg
 14.5 pounds
~6.6 kg
15.6 pounds
~7.1 kg
Cables AC - 72 inches (~183 cm)
DC - 78 inches (~198 cm)
AC - 72 inches (~183 cm)
DC - 78 inches (~198 cm)
AC - 72 inches (~183 cm)
DC - 78 inches (~198 cm)
AC - 72 inches (~183 cm)
DC - 78 inches (~198 cm)
Amazon Link NOCO GEN1 NOCO GEN2 NOCO GEN3 NOCO GEN4

Note: Amazon links in the table are affiliate links.

NOCO Genius GEN Battery Chargers are very similar to NOCO Genius GEN Mini chargers, except they charge batteries with max 10 Amps per line. Hence, they are larger, heavier and they cost little bit more.

Main difference is recommended battery size - between 25 and 230 Ah.

NOCO Genius GEN Mini and GEN Charging Times

Battery charging times depends on the discharge level, battery capacity and charging current. Charging times of 50% discharged batteries is given in the following table:

Battery Capacity (Ah) NOCO GEN Mini Series (4 Amps) Battery Capacity (Ah) NOCO GEN Series (10 Amps)
20 Ah 2.5 h 25 Ah 1.3 h
30 Ah 3.7 h 50 Ah 2.5 h
40 Ah  5 h 60 Ah 3.0 h
50 Ah  6.2 h 70 Ah 3.5 h
60 Ah  7.5 h 80 Ah 4.0 h
70 Ah  8.7 h 90 Ah 4.5 h
80 Ah  10.0 h 100 Ah 5 h
90 Ah  11.2 h 125 Ah 6.3 h
100 Ah  12.5 h 150 Ah 7.5 h
110 Ah  13.7 h 200 Ah 10 h
120 Ah  15 h 230 Ah  11.5 h

Modern lead acid batteries can be charged with larger currents than 'old wet cells', however, regular charging with such currents can in the end, shorten their operating life, too. IMHO, for the batteries up to 30-35 Ah, choose GENM (4 A) chargers, and for larger batteries choose any of them according to your personal needs and requirements.

If you charge your batteries over night and you require to fully charge the 50% discharged batteries, maximum recommended battery size for the GENM (4 A) charger is around 64 Ah and for the GEN (10 A) charger is around 160 Ah.

Note: if you discharge your batteries down to 25% (don't go below 20-25%!), and you want them to be fully charged after 8 hours of charging, than your maximum battery size for GENM (4 A) charger is around 43 Ah and for the GEN (10 A) charger is around 107 Ah.

Since bulk charge phase, absorption charge phase and optimization phase don't charge the batteries with the same current, these maximum recommended battery sizes should be taken with the reserve, or instead of charging them for 8 hours, charge them for 9-10 hours.

For more information about charging phases and other technical data, be sure to read User Guide, Datasheet and the Warranty of the chargers, before you turn them on for the first time! Better safe than sorry! :)


 Long story short - NOCO Genius GEN Mini Series and GEN Series chargers are excellent and very robust and durable lead acid battery chargers. They will do their job properly, just don't abuse them, at least not too much.

And whatever you do, it is your own responsibility. If you are not sure, ask for professional help. It is in the interest of all companies (NOCO included, of course) to develop the best possible relationship with their customers, both old and new!