A device maintenance apparatus , comprising: a communicator configured to acquire device information from a field device installed in a plant; and a display data generator configured to generate first display data for displaying a main page, the main page comprising the acquired device information , maintenance items associated with the acquired device information and a maintenance item button configured to receive determination of a maintenance item among the maintenance items associated with the acquired device information, wherein in a case in which the maintenance item button receives the determination of the maintenance item, the display data generator is configured to generate second display data for displaying a setting page of the determined maintenance item, the setting page comprises: a setting operator configured to allow for setting a test pattern, the test pattern being set to define a change of output signals output from the field device over time, the output signals output from the field device being input into a host device in a case in which the determined maintenance item is a test which makes the field device input output signals of a predetermined output level into the host device; and an execution operator configured to make the field device output the output signals based on the set test pattern, characterized in that the setting operator comprises a first setting and a second setting , the first setting being configured to allow for independently setting each output level of the output signals at each of a plurality of intervals of time, the output level of the output signals transitioning in the test pattern, the second setting being configured to allow for setting the intervals of time a communicator configured to acquire device information from a field device installed in a plant; and a display data generator configured to generate first display data for displaying a main page, the main page comprising the acquired device information , maintenance items associated with the acquired device information and a maintenance item button configured to receive determination of a maintenance item among the maintenance items associated with the acquired device information, wherein in a case in which the maintenance item button receives the determination of the maintenance item, the display data generator is configured to generate second display data for displaying a setting page of the determined maintenance item, the setting page comprises: a setting operator configured to allow for setting a test pattern, the test pattern being set to define a change of output signals output from the field device over time, the output signals output from the field device being input into a host device in a case in which the determined maintenance item is a test which makes the field device input output signals of a predetermined output level into the host device; and an execution operator configured to make the field device output the output signals based on the set test pattern, a setting operator configured to allow for setting a test pattern, the test pattern being set to define a change of output signals output from the field device over time, the output signals output from the field device being input into a host device in a case in which the determined maintenance item is a test which makes the field device input output signals of a predetermined output level into the host device; and an execution operator configured to make the field device output the output signals based on the set test pattern, characterized in that the setting operator comprises a first setting and a second setting , the first setting being configured to allow for independently setting each output level of the output signals at each of a plurality of intervals of time, the output level of the output signals transitioning in the test pattern, the second setting being configured to allow for setting the intervals of time <EOS>