This work aims to develop nine ammeters, from the combination of three boards designed in the program Eagle 7.7 Cadsoft, prototyped with up to two types of shields manufacturer Maglab. Each of these plates has one, two or three turns of current chain track, together with the type U12 and R1 shields manufactured by Maglab. In each of these nine combinations, with the aid of precision laboratory instruments, such as a source, oscilloscope and multimeter, electrical current measurements of -3A up to 3A were taken, passing through 0A (no current) and varying the current every 1 A. From the data collection, the mean, standard deviation and coefficient of variation of the measurements were calculated to determine the precision and accuracy of the nine designed multimeter and to choose the most suitable to monitor a lithium-ion battery charger, which performs the charge of a Powerizer manufacturer s 12600 mAh lithium-ion battery pack, with load current up to 6 A in direct current.