An instance data block is assigned to every function block call that transfers parameters. The actual parameters and the static data of the FB are saved in the instance DB. The variables declared in the FB determine the structure of the instance data block. Instance means a function block call. If, for example, a function block is called five times in the S7 user program, there are five instances of this block. Creating an Instance DB Before you create an instance data block, the corresponding FB must already exist. You specify the number of the FB when you create the instance data block. One Instance DB for Each Separate Instance If you assign several instance data blocks to a function block (FB) that controls a motor, you can use this FB to control different motors. The data for each specific motor (for example, speed, runup time, total operating time) are saved in different data blocks. The DB associated with the FB when it is called determines which motor is controlled. With this technique, only one function block is necessary for several motors