About Tags and the Project Database • Control tags • Auxiliary tags used to perform mathematical calculations • Shared Database tags are created in a PC-based control program and then imported into IWS's tags database. For example you might create tags in SteepleChase and import them into IWS so IWS can read/write data from a SteepleChase PC-based control product. You cannot modify shared tags within IWS — you must modify the tags in the original PC-based control program, and then re-import them into the Tags database. • System Tags are predefined tags with predetermined functions that are used for IWS supervisory tasks.
For example, • Date tags hold the current date in string format • Time tags hold the current time in string format Most system tags are read-only , which means you cannot add, edit, or remove these tags from the database. To see a list of the system tags, select the Global tab in the Project Explorer , open the System Tags folder, and open the Tag List subfolder. The above figure shows a partial list of system tags. After creating a tag, you can use it anywhere within the project, and you can use the same tag for more than one object or attribute. Page 50