In this image I am testing the Smart Gauge with a 400Ah LiFeP04 battery bank. This is the only type of battery it failed to track accurately. Not a big deal as it was never designed for Li batteries and very few boat owners use Li.


I found it quite interesting that while trying to find the actual capacity of some of the used lead acid batteries the Smart Gauge was already accurate by the second cycle and I was on my third complete discharge capacity test before finding an accurate new 20 hour rating for the battery to test it at..


How accurate? It is tough to say precisely because I really don't know how much I trust the Ah counters. Suffice it to say it was most likely as accurate than the Ah counters and probably below a 3% variation in SOC. I don't have the test equipment resolution to make claims of 1% like EnerSys does, but even if under 5% this is simply OUTSTANDING!!


The SGBMU was lining up with my two Ah counters, once the banks were well calibrated to the Ah counters (arghh what a process), to under a 2% - 3% variance. In many cases the Smart Gauge beat me to the actual SOC.... The Smart Gauge found the SOC of the used batteries faster than I could doing actual physical 20 hour capacity tests. Truly amazing.


The Smart Gauge seems to work as advertised on GEL, AGM and FLA batteries in discharge mode.


What does that mean?


It means that I did see the Smart Gauge get a bit confused when the bank was being charged. It can't really track the capacity of a battery charger now can it...? However we are only talking about 10-12% variation from the Ah counters during charging, and not a huge deal when you consider how simple this battery monitoring unit is. Another issue with tracking SOC during charging is charge efficiency variations so it was much easier to do this testing on the discharge side of the equation..


As soon as the charge source was discontinued, the Smart Gauge fairly quickly identified the accurate SOC of the bank again, and was back within approx 2% - 3% of the two painstakingly calibrated Ah counters.




WHAT THE SMART GAUGE DOES:


*It tracks the voltage of the battery bank up to 1500 times per second and over time learns bank behavior, WITH NO HUMAN INTERVENTION or COMPLICATED PROGRAMING! As time goes on it gets smarter and smarter and more and more accurate. This is GOOD! Traditional battery monitors may start out close to accurate but as time goes on they lose accuracy. It may check internal impedance but I failed to witness this occurring.


*It needs a good three to four cycles for it to hone in on SOC and the longer it remains connected the smarter and more accurate it gets. I attempted 5-8 cycles on each bank beyond the capacity tests.


*It provides voltage of the HOUSE and START/AUX banks in 0.05V increments.


*It identifies SOC of the HOUSE bank irrespective of age or condition.


*For SOC readings it requires no programing beyond selecting the battery type and wiring it directly to the battery positive and negative posts of the HOUSE bank.


*It removes the guess work and tediousness of programing a traditional Ah counter.


*It is the easiest to use battery monitoring unit I have ever seen.


*Works with either 12V or 24V banks and automatically detects this when connected.


*Offers low and high voltage alarm relay trigger ports. These ports can even be used to start a generator if your vessel is so equipped.


*Requires no shunts or heavy gauge wiring. Hooks up with simple 14GA wire. No battery lugs to crimp.


*It tells you all you really want or need to know to maximize your battery banks cycle life, the state of charge. It really does not matter what your "capacity" is just that what ever it is, you are not constantly pulling the bank below 50% SOC.