A field device comprising: measurement circuitry for determining a value of a process variable using energy received via a two-wire current loop; loop current circuitry for controlling a loop current (I L) flowing through the current loop; voltage measurement circuitry for providing a signal indicative of a voltage (V T) received by the field device from the current loop; and a controller coupled to the measurement circuitry, the loop current circuitry, and the voltage measurement circuitry, the controller being configured to: acquire a first value of the process variable from the measurement circuitry; determine if the voltage (V T) received by the field device from the current loop is sufficient to support a first loop current representing the first value of the process variable; control, when it is determined that the voltage (V T) received by the field device from the current loop is insufficient to support the first loop current, the loop current circuitry to control the loop current (I L) to an alarm current lower than a predefined alarm threshold current; acquire a second value of the process variable from the measurement circuitry and a signal from the voltage measurement circuitry indicating a present voltage (V T) received by the field device from the current loop; determine a second loop current representing the second value of the process variable; determine, based on the signal indicating the present voltage (V T) received by the field device from the current loop and an estimation of a loop impedance (R L) of the current loop as seen by the field device, whether or not the present voltage (V T) received by the field device from the current loop is sufficient for supporting the second loop current; and control, when it is determined that the present voltage (V T) received by the field device from the current loop is sufficient for supporting the second loop current, the loop current circuitry to change the loop current (I L) from the alarm current to the second loop current. measurement circuitry for determining a value of a process variable using energy received via a two-wire current loop; loop current circuitry for controlling a loop current (I L) flowing through the current loop; voltage measurement circuitry for providing a signal indicative of a voltage (V T) received by the field device from the current loop; and a controller coupled to the measurement circuitry, the loop current circuitry, and the voltage measurement circuitry, the controller being configured to: acquire a first value of the process variable from the measurement circuitry; determine if the voltage (V T) received by the field device from the current loop is sufficient to support a first loop current representing the first value of the process variable; control, when it is determined that the voltage (V T) received by the field device from the current loop is insufficient to support the first loop current, the loop current circuitry to control the loop current (I L) to an alarm current lower than a predefined alarm threshold current; acquire a second value of the process variable from the measurement circuitry and a signal from the voltage measurement circuitry indicating a present voltage (V T) received by the field device from the current loop; determine a second loop current representing the second value of the process variable; determine, based on the signal indicating the present voltage (V T) received by the field device from the current loop and an estimation of a loop impedance (R L) of the current loop as seen by the field device, whether or not the present voltage (V T) received by the field device from the current loop is sufficient for supporting the second loop current; and control, when it is determined that the present voltage (V T) received by the field device from the current loop is sufficient for supporting the second loop current, the loop current circuitry to change the loop current (I L) from the alarm current to the second loop current. acquire a first value of the process variable from the measurement circuitry; determine if the voltage (V T) received by the field device from the current loop is sufficient to support a first loop current representing the first value of the process variable; control, when it is determined that the voltage (V T) received by the field device from the current loop is insufficient to support the first loop current, the loop current circuitry to control the loop current (I L) to an alarm current lower than a predefined alarm threshold current; acquire a second value of the process variable from the measurement circuitry and a signal from the voltage measurement circuitry indicating a present voltage (V T) received by the field device from the current loop; determine a second loop current representing the second value of the process variable; determine, based on the signal indicating the present voltage (V T) received by the field device from the current loop and an estimation of a loop impedance (R L) of the current loop as seen by the field device, whether or not the present voltage (V T) received by the field device from the current loop is sufficient for supporting the second loop current; and control, when it is determined that the present voltage (V T) received by the field device from the current loop is sufficient for supporting the second loop current, the loop current circuitry to change the loop current (I L) from the alarm current to the second loop current.