Spare items are elements that are not drawn in the schematic. These devices can, if requested, be included in the bill of materials output. Any type of device can be managed as spares. Terminals, cables, contactors, motors, PLCs etc.

Spares are thus not displayed in the schematic, or the overview pages or the mounting panel. Elements contained in such pages are not regarded as spares.

Reserve items are normally managed as spare parts For this reason, it also makes no sense to assign them a device tag, since when the project is finished, all device tags that are not drawn are logged as errors.

In contrast to this, devices are logical electronic or fluid-technical (hydraulic or pneumatic) units that are identified by a device tag (DT). Unplaced devices may still occur in a project, e.g. through pre-definition, but when the project is finished, unplaced devices are regarded as errors.