Patent attributes
A measurement instrument reads information on the guarantee number-of-measurements issued depending on the payment of purchased consumables from a magnetic card (21), stores the information in a guarantee number of measurements storage unit (31), stores the actual number of measurements in a number of measurements storage unit (32), stores the remainder of subtraction of the actual number of measurements stored in the number of measurements storage unit (32) from the guarantee number of measurements stored in the guarantee number of measurements storage unit (31) in a remainder storage unit (33). When the remainder reaches a predetermined value, the measurement instrument outputs a message to invite to purchase a new magnetic card to a display unit (4).
