Scan Tool Testing and Procedures
RTD Data Parameter Display:
Data
When one of the various data tests is selected, the actual analog value as seen/used by the system is displayed.
Inputs
Input tests will display the state of the selected device as HI or LO. The display also indicates if the input changed state so that the technician can activate or deactivate any listed device and return to the display to see if it changed state. If a change of state occurred, an "X" will appear next to the HI/LO indicator, otherwise a "0" will remain displayed. The "X" will only appear once per selected input although the HI/LO indication will continue to change as the input changes. Some tests are momentary and the "X" can be used as an indication of a change.
Outputs
Output cycling can be used to determine if the output tests can be actuated regardless of the inputs and normal program instructions. Once a test in outputs has been selected, the test will display HI and LO for three seconds in each state to indicate the command and output terminal voltage.