Diagnostic apparatus

A diagnostic apparatus that diagnoses a degree of wear of a belt that is provided in an industrial machine and transmits power, comprising:

• a control unit configured to control a diagnostic operation for driving the belt;
• wherein the diagnostic operation comprises:
• (i) issuing a command causing the belt to be driven at a plurality of position of the belt or under or a plurality of conditions and (ii) issuing a command causing one or more sensors to acquire detection value data under the plurality of conditions;
• a first tension calculation unit configured to perform, based on data obtained from the diagnostic operation, a calculation to estimate a first belt tension value that is a tension value of the belt when the belt is not worn;
• a second tension calculation unit configured to calculate a second belt tension value in a case where a tension reduction factor of the belt and a wear factor of the belt are included;
• and a third tension calculation unit configured to calculate the degree of wear of the belt based on the first belt tension value and the second belt tension value;
• wherein the third tension calculation unit calculates the degree of wear in accordance with iterations of the diagnostic operation.