NorthStar AGM BCI Group 27 Batteries - NSB-AGM27, NSB-AGM27F and NSB-AGM27M Batteries
NorthStar NSB-AGM27, NSB-AGM27F and NSB-AGM27M are versatile, dual purpose, BCI Group 27 batteries, designed to be durable and reliable power source for even the most demanding applications.
NortStar NSB-AGM27, NSB-AGM27F and NSB-AGM27M batteries are essentially the same battery, differing only in their terminal posts - depending on their intended use.
Updated: October 16, 2019.
NorthStar NSB-AGM27, NSB-AGM27F, NSB-AGM27M Features and Specifications
NorthStar NSB-AGM27, NSB-AGM27F and NSB-AGM27M batteries are BCI Group 27 batteries and their physical dimensions are (L x W x H) 12.4 x 6.77 x 8.74 inches (316 x 172 x 222 mm).
Note: we are really trying to verify every single bit of information before posting it on our site and to provide our honest opinion. Having that in mind, note that BCI battery standard sizes of Group 27 and Group 27F are not the same:
- Group 27 size: 12.0625 x 6.8125 x 8.875 inches, 306 x 173 x 225 mm,
- Group 27F size: 12.5 x 6.8125 x 8.9375 inches, 318 x 173 x 227 mm.
All three models fit BCI Group 27F size, but NSB-AGM27 and NSB-27M models belong, at least in theory, to the BCI Group 27F and NOT to BCI Group 27.
Personally, this is very small difference and in most situations this is not that important. But, it is nice to know. Also, it is not uncommon - we have seen larger differences in the actual battery sizes and stated BCI Groups.
NorthStar NSB-AGM27, NSB-AGM27F and NSB-AGM27M batteries are far from being lightweight - they weigh 68 pounds (~30.8 kg).
Their nominal voltage is 12 volts and their nominal 20h capacity is 92 Ah (down to 10.5 volts, or 1.75 volts per cell).
NorthStar NSB-AGM27, NSB-AGM27F and NSB-AGM27M batteries use pure lead plates in order to achieve good CCA/MCA ratings, good RC value, fast recharging, and to support large number of deep charge/discharge cycles.
These batteries are AGM (Absorbent Glass Mat) batteries, which means that diluted sulfuric acid is absorbed in the glass mat between lead plates and it is designed to be spill proof (SLA Battery - Sealed Lead Acid Battery). Thus, they can operate in any position and are almost maintenance free batteries - just be sure that there is no corrosion between terminals and cables. Also, they feature high resistance to vibration, leading to longer operational life, especially in the off-road and marine applications.
NorthStar NSB-AGM27, NSB-AGM27F and NSB-AGM27M batteries feature 930 Amps CCA (Cold Cranking Amps) rating - new, fully charged batteries are able to provide 930 Amps for 30 seconds with the voltage NOT dropping below 7.2V at 0°F (-18°C). And that is very cold weather!
Also, they feature 1080 Amps CA/MCA (Cranking Amps/Marine Cranking Amps) rating - new, fully charged batteries are able to provide 1080 Amps for 30 seconds with the voltage NOT dropping below 7.2V at 32°F (0°C).
NorthStar doesn't state their HCA (Hot Cranking Amps, max current at 80°F (27°C) for 30 seconds), but they state their PCA (Pulse Cranking Amps) of 1750 Amps, without stating the temperature and duration. In the worst case scenario, it is safe to assume 3s pulse at 80°F (27°C) or 77°F (25°C).
In any case, 1750 Amps is a lot of power!
NorthStar NSB-AGM27, NSB-AGM27F and NSB-AGM27M batteries feature internal resistance of 2.6 mΩ (measured at 77°F, 25°C ) and short circuit current of 5000 Amps.
Reserve Capacity is rated at 195 minutes - new, fully charged batteries are able to provide 25 Amps for 195 minutes without the voltage dropping below 10.5 volts (1.75 volts per cell).
According to their manufacturer, NorthStar NSB-AGM27, NSB-AGM27F and NSB-AGM27M batteries are able to withstand:
- over 900 cycles to 50% Depth of Discharge (DoD), or to 50% State of Charge (SoC),
- over 400 cycles to 80% Depth of Discharge (DoD), or to 20% State of Charge (SoC).
Note that these batteries come with 3-year warranty, which is not so common for AGM SLA batteries.
NorthStar NSB-AGM27 and NSB-AGM27F Batteries
NorthStar NSB-AGM27 and NSB-AGM27F batteries are two very similar models. They both feature SAE automotive posts, with NSB-AGM27 having positive post on the left side (observed from the front), while NSB-AGM27F features positive post on the right side (observed from the front).
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NorthStar NSB-AGM27 and NSB-AGM27F are automotive batteries, intended as dual purpose batteries in the single battery automotive electric systems.
As such, they offer strong starting currents, but they are also able to provide energy while the main engine is turned off to electric and electronic system commonly found in the cars, trucks, RV and similar vehicles, like alarms, GPS, audio system, winches, lights, DC/DC and DC/AC converters and similar.
Also, NorthStar NSB-AGM27 and NSB-AGM27F are used in the off-the-grid applications where their deep cycle performances are required.
In the security and UPS systems, medical applications, and similar, NorthStar NSB-AGM27 and NSB-AGM27F can be used as standby batteries, being ready to provide required energy at the moment notice, regardless of the load.
NorthStar NSB-AGM27M Marine Battery
NorthStar NSB-AGM27M features two types of posts: SAE automotive posts and marine posts, with the positive posts being on the left side, when the battery is observed from the front.
NorthStar NSB-AGM27M can be used in any application like NorthStar NSB-AGM27 battery, as long as the pair of marine posts don't interfere with the cables.
NorthStar NSB-AGM27M can be also used in:
- the boats/yachts with a single battery electric system - for starting the main engine(s) and for powering the systems while the main engine(s) are off.
- the boats/yachts with a two battery electric system - as starting battery, it can start even large diesel engines easily, and as deep cycle battery, it tolerates large number of charging/discharging cycles and can be quickly recharged using onboard alternator(s) or some intelligent AGM battery charger.
- as electric trolling motor battery - it can supply 25 Amps for 195 minutes (3 hours and 15 minutes). If larger capacity is required, two or more batteries can be connected in parallel.
Long Story Short: if you are looking for a good and reliable, dual purpose group 27 battery, consider one of these and choose according to your needs.
NorthStar NSB-AGM27, NSB-AGM27F and NSB-AGM27M batteries are not cheap batteries, but they have excellent performances and come with not-so-common 3-year warranty.
For more reviews and recommendations, check these Amazon links:
- NorthStar NSB-AGM27F Battery
- NorthStar NSB-AGM-27M Battery
Links open in the new windows.