App note from Murata about digital ammeter and things to consider implementing them. Link here (PDF)
There is a trend to replace older, analog-style readouts with modern digital displays. As one might expect, the conversion is not always a trivial task. This is especially true when the conversion involves older, moving-vane (“pointer” style) analog ammeters. The typical analog ammeter has only two wires to contend with, and the required shunt resistor is sometimes built-in to the meter itself. By comparison, its digital replacement may have as many as fi ve or six input terminals. The project gets even more complicated when you include the required external current shunt. Hopefully, after reading this application note, you will have the necessary information to avoid the most common pitfalls associated with digital ammeter installations.