A test system (1, X100) for measuring gas ingredients in sampled intake and/or exhaust gas of an internal-combustion engine, the test system (1, X100) comprising: a plurality of testing devices used for the measuring, wherein each of the testing devices comprising a plurality of components, wherein each of the plurality of testing devices is configured to be operable in and switched among at least first and second operational modes in which at least one of the components of the testing device is set to operate in the first operational mode of the testing device, and set to not operate while other of the components of the testing device operate in the second operational mode of the testing device, and wherein each of the plurality of testing devices includes a local computer that calculates a measured value indicating a concentration of each ingredient in the sampled gas; a device-managing device communicably connected to the plurality of testing devices and configured to manage the plurality of testing devices, a history-information acquiring unit (46, X54) for acquiring, for each of the plurality of testing devices, operating history information indicating operating history including accumulating operating time of each the plurality of components, wherein in accumulating the operating time of each of the plurality of components, the history-information acquiring unit (46, X54) accumulates the operating time of the component only in the operational modes for which the component is set to operate and not in the operational modes for which the component is set to not operate; and an accepting unit for accepting setting data to set, for each of the plurality of testing devices, predetermined operational modes, wherein the setting data indicates whether each of the plurality of components of the testing device should operate. a plurality of testing devices used for the measuring, wherein each of the testing devices comprising a plurality of components, wherein each of the plurality of testing devices is configured to be operable in and switched among at least first and second operational modes in which at least one of the components of the testing device is set to operate in the first operational mode of the testing device, and set to not operate while other of the components of the testing device operate in the second operational mode of the testing device, and wherein each of the plurality of testing devices includes a local computer that calculates a measured value indicating a concentration of each ingredient in the sampled gas; each of the plurality of testing devices is configured to be operable in and switched among at least first and second operational modes in which at least one of the components of the testing device is set to operate in the first operational mode of the testing device, and set to not operate while other of the components of the testing device operate in the second operational mode of the testing device, and wherein each of the plurality of testing devices includes a local computer that calculates a measured value indicating a concentration of each ingredient in the sampled gas; a device-managing device communicably connected to the plurality of testing devices and configured to manage the plurality of testing devices, a history-information acquiring unit (46, X54) for acquiring, for each of the plurality of testing devices, operating history information indicating operating history including accumulating operating time of each the plurality of components, wherein in accumulating the operating time of each of the plurality of components, the history-information acquiring unit (46, X54) accumulates the operating time of the component only in the operational modes for which the component is set to operate and not in the operational modes for which the component is set to not operate; and an accepting unit for accepting setting data to set, for each of the plurality of testing devices, predetermined operational modes, wherein the setting data indicates whether each of the plurality of components of the testing device should operate.