An APL field switch (30, 32) for an industrial control network that enables user-selectable dynamic power allocation to a connected field device (26, 36, 40), the APL field switch (30, 32) comprising: power terminals (35, 37) and data terminals that are each configured to receive power into the APL field switch (30, 32), the data terminals being further configured to transmit data into and out of the APL field switch (30, 32); a plurality of channels, each channel comprising a port and a channel power/data line (43, 47) connecting the port to the power terminals (35, 37) and data terminals; each port of the plurality of channels being configured to be connected to a two-wire APL spur for connecting the port to an APL field device (26, 36, 40) through the APL spur, the port being associated with a default Power Class of a plurality of Power Classes; the channel power/data line (43, 47) of each channel being configured to transmit power from the power terminals (35, 37) to the channel port and to transmit data between the channel port and the data terminals, the channel power/data line (43, 47) comprising a power line segment connected to the channel port and configured to transmit electrical power received from the power terminals (35, 37) to the channel port; an adjustable power-limiting device being disposed in the power line segment, the power-limiting device being capable of being selectively operated in a plurality of respective operating states wherein when the power-limiting device is in one of the operating states of the plurality of operating states a respective maximum transmission of electrical power through the power-limiting device activates the power-limiting device and thereby limits, reduces, or stops the transmission of electrical power through the power line segment, each operating state being associated with a different Power Class; and a controller being connected to the power-limiting device of each channel of the plurality of channels, the controller comprising a computer software program incorporated in an executable non-transitory computer-readable medium for operating the controller, the controller being configured to receive a user input requesting the controller to set a Power Class of a selected port of the plurality of channels to a desired Power Class and in response to the user input issue a control signal through the connection to the power-limiting device connected to the selected port that sets the operating state of the power-limiting device to the operating state associated with the desired Power Class, whereby the user may selectively change the Power Class of each port to meet the needs of the industrial control network. power terminals (35, 37) and data terminals that are each configured to receive power into the APL field switch (30, 32), the data terminals being further configured to transmit data into and out of the APL field switch (30, 32); a plurality of channels, each channel comprising a port and a channel power/data line (43, 47) connecting the port to the power terminals (35, 37) and data terminals; each port of the plurality of channels being configured to be connected to a two-wire APL spur for connecting the port to an APL field device (26, 36, 40) through the APL spur, the port being associated with a default Power Class of a plurality of Power Classes; the channel power/data line (43, 47) of each channel being configured to transmit power from the power terminals (35, 37) to the channel port and to transmit data between the channel port and the data terminals, the channel power/data line (43, 47) comprising a power line segment connected to the channel port and configured to transmit electrical power received from the power terminals (35, 37) to the channel port; an adjustable power-limiting device being disposed in the power line segment, the power-limiting device being capable of being selectively operated in a plurality of respective operating states wherein when the power-limiting device is in one of the operating states of the plurality of operating states a respective maximum transmission of electrical power through the power-limiting device activates the power-limiting device and thereby limits, reduces, or stops the transmission of electrical power through the power line segment, each operating state being associated with a different Power Class; and a controller being connected to the power-limiting device of each channel of the plurality of channels, the controller comprising a computer software program incorporated in an executable non-transitory computer-readable medium for operating the controller, the controller being configured to receive a user input requesting the controller to set a Power Class of a selected port of the plurality of channels to a desired Power Class and in response to the user input issue a control signal through the connection to the power-limiting device connected to the selected port that sets the operating state of the power-limiting device to the operating state associated with the desired Power Class, whereby the user may selectively change the Power Class of each port to meet the needs of the industrial control network.