Questionable Data
When the data being reported by a piece of equipment is in doubt for any reason, it is marked as questionable so that operators using the application are aware that the equipment has to be checked and its data confirmed against the data being reported. An example of a questionable data display is shown below.
The question marks appearing in the tank's pressure value and level displays above are questionable data indicators.
Once the problem is resolved and the incoming data is confirmed as accurate, the questionable data indicator can be removed.
Once the incoming data is validated against the equipment's readings, the questionable data indicators can be removed.
Questionable data is used for commissioning purposes, when signals are being checked to ensure that they are reliable. During commissioning, all data for an application is marked as questionable. The data for each piece of physical equipment in the system is then checked. When the data reported by piece of physical equipment and the data of its corresponding VTS tag are found to match, the signal is deemed reliable and the questionable data indicator can be turned off at the discretion of an operator who is authorized to do so.
Information on marking data as questionable is provided in Questionable Data Shortcut Menu Option.
Note: The ability to mark data as questionable and to enter manual data are user privileges that may not have been assigned to you. Ask your VTS developer which user privileges you've been assigned.