Seriously, welcome to my world. Looks like someone spilled spaghetti in the battery compartment... OUCH!!!


Believe it or not there is a shunt for a traditional Ah/Coulomb counter at the bottom of this picture. It is smack dab in the middle with the two brass squares. It was so grossly mis-wired there was no chance in hell it could even be close to accurate.


Traditional Ah counters rely on shunts to measure amperage flowing into or out of the bank. In reality a shunt does not measure amperage, it measures voltage drop at the mV level. The Ah counter transposes this into displayed amperage or Ah's consumed or replaced...


The shunt in this image is a typical 500A X 50mV shunt that comes with many Ah counters. This nomenclature simply means that at 500A of current there will be a 50mV drop between the first brass square and the second brass square. A sense wire on each of the brass squares measures the mV drop or difference. Every point in between 0A and 500A has a known calibrated value the battery monitor transposes to current.


Think of a shunt as the electric meter for your house. If you climbed the pole and ran an extension cord directly to the live wires, and then began running your fridge on it, the electric company could not charge you for the fridge use because their meter could not see this use.


Any time a wire sneaks in front of a shunt, a sneaker wire, it essentially does the same thing, it bypasses the battery monitor. With sneaker wires bypassing the Ah counter it can't see it, so it can't record it. Wiring shunts is not difficult but I see about 70% +/- of them wired incorrectly, even by pro's.. With an improperly wired shunt nothing you do to program the Ah counter will help save you.


Thankfully Smart Gauge uses no shunt, it is a shunt-less design. This means there are no large gauge battery lugs to crimp, no large gauge jumper wires to make up, and there is no complicated programing beyond selecting the battery type. This makes the Smart Gauge a DIY's dream battery monitor. Easy, simple, never needs programing and stays accurate despite temperature, battery age/condition or a nuclear holocaust. Just seeing if you are still paying attention...


I almost hate mentioning this product here because I trouble shoot a lot of Ah counters but when I see a good product I like to pass it onto my readers..... (wink)