Optional slaves

The principle of optional slaves works as follows:

• All optional slaves must have been configured in the Configurator.
• But slaves marked as "optional" may be missing in the unit structure from perspective of the hardware. The master will still start.

This offers the advantage that you can create projects with devices that are available only partially in the plant. The project remains unchanged.

The following applies when using optional slaves:

• The master detects only optional slaves that are connected in terms of hardware when starting the master.
• Optional slaves that are added during ongoing operation will not be detected by the master until restart.
• Optional slaves need an explicit device identification either via ID selection with hardware DIP switch or via station alias.