Current meter device comprising: an input connector device for operatively connecting said current meter device removably to at least one adapter device, said adapter device being connectable to the power supply mains; an output connector device for operatively connecting said current meter device removably to at least one charging element, said charging element being operatively connectable to at least one device to be charged having at least one rechargeable battery; a current reader for reading the electric current flowing between the input connector device and the output connector device; and at least one switch for operatively connecting the device to be charged by the charging element to said current meter device and then to the adapter when the charging phase of said element to be charged begins, and for disconnecting the device to be charged from said current meter device when the electrical current read by the current reader is lower than a current threshold and the charging phase has finished characterized in that the current meter device further comprises a timer system to adjust the activation of the switch, in particular to delay or prevent the activation and/or deactivation of the switch, wherein the timer system consists only of a capacitor and a resistive network (R3, R5), in particular a first resistor and a second resistor and wherein the output of said timer system is maintained as if the current read is below the current threshold if one or more current pulses absorbed by the device to be charged exceed said current threshold when said device to be charged has reached the end of charging. an input connector device for operatively connecting said current meter device removably to at least one adapter device, said adapter device being connectable to the power supply mains; an output connector device for operatively connecting said current meter device removably to at least one charging element, said charging element being operatively connectable to at least one device to be charged having at least one rechargeable battery; a current reader for reading the electric current flowing between the input connector device and the output connector device; and at least one switch for operatively connecting the device to be charged by the charging element to said current meter device and then to the adapter when the charging phase of said element to be charged begins, and for disconnecting the device to be charged from said current meter device when the electrical current read by the current reader is lower than a current threshold and the charging phase has finished characterized in that the current meter device further comprises a timer system to adjust the activation of the switch, in particular to delay or prevent the activation and/or deactivation of the switch, wherein the timer system consists only of a capacitor and a resistive network (R3, R5), in particular a first resistor and a second resistor and wherein the output of said timer system is maintained as if the current read is below the current threshold if one or more current pulses absorbed by the device to be charged exceed said current threshold when said device to be charged has reached the end of charging.