PLC Subdevices

Specific PLC devices consist of multiple integrated modules, that each have their own address ranges and start addresses. Such a device can consist, for example, of an internal CPU module, an internal input / output module as well as internal counter module - however with only one part number. Such integrated modules within a PLC device can be displayed in EPLAN with PLC subdevices. To this purpose up to twelve PLC subdevices are available. The PLC subdevices are considered in the AutomationML format during a PLC data exchange. The device data for the main device and the associated PLC subdevices are maintained once per device by the manufacturer in the parts management.

Each PLC subdevice is defined by the corresponding properties ("x" in the following section designates the number of the PLC subdevice 1…12).

Required properties

PLC subdevice x: Name: Device name of the logical function unit.
PLC subdevice x: Position (slot / module): Specifies on which slot / at which position on the PLC card this PLC subdevice is located.
PLC subdevice x: Start address (inputs): Start address for the inputs of the PLC subdevice x.
PLC subdevice x: Start address (outputs): Start address for the outputs of the PLC subdevice x.

The properties PLC subdevice: Name and PLC subdevice x: Position (slot / module) identify the PLC subdevice and must be filled at the PLC box in the project. By means of the part selection these properties are filled with the values from the parts database. You use the properties PLC subdevice x: Start address (inputs) and PLC subdevice x: Start address (outputs) to specify the associated start addresses for the PLC subdevices at the PLC box.

PLC subdevices are exported if they have at least one start address or one bus port or one I/O connection point or one device identification.

At a PLC connection point (I/O connection point or bus port) specify the PLC subdevice to which the connection point belongs in the PLC subdevice: Index property. For example, the index value "3" means that the PLC connection point belongs to the PLC subdevice 3. This information is required for automatic addressing and for the PLC data exchange in the AutomationML format. The property can also be stored in the function templates of the parts and is transferred to the PLC connection points for a device selection or when inserting devices.

Note:

The properties for the start address are now available at the PLC box in the project and not in the parts management.

Optional properties

PLC subdevice x: Data length (inputs): Required length in the address space for the inputs of PLC subdevice x. The specification is in bits.
PLC subdevice x: Data length (outputs): Required length in the address space for the outputs of PLC subdevice x. The specification is in bits.

The properties for the data length are only used for check runs and for the output of the address space assignment.

The address range of the PLC subdevice is determined from the data length together with the start address. Note that there are PLC cards, for example technology modules, which are only assigned to a few inputs / outputs, but still require a larger address range than the one currently occupied. Always enter the maximum required length for the address range of the inputs or outputs here.

Special properties

The following properties only used for the device identification of PLC subdevices that are managed in the PLC configuration program as independent devices.

PLC subdevice x: PLC type designation: PLC type designation for PLC subdevice x of a PLC card.
PLC subdevice x: Device description: Index in file: Reference to the device in the device description file that is entered at the PLC box (main device) in the property Device description: File name.

Device identification / Part allocation of PLC subdevices

Identification via the main device

For PLC subdevices that are treated in the PLC configuration program as integrated devices, the Device identification and the Part allocation take place during the import of PLC configuration files, only by means of the PLC type designation or the device description file that is entered at the PLC box of the main device. In this case leave the properties PLC subdevice x: PLC type designation and PLC subdevice x: Device description: Index in file empty.

Identification via multiple PLC type designations or multiple indexes in the device description file

For PLC subdevices that are treated as independent devices in the PLC configuration program, the device identification takes place by means of the properties PLC subdevice x: PLC type designation or PLC subdevice x: Device description: Index in file.

Note:

The device identification for the main device and the associated PLC subdevices must be carried out in the same way. If, for example, a PLC type designation is specified at the PLC box, the PLC subdevices must be defined via a PLC type designation.

The PLC subdevice x: PLC type designation property has to be filled with PLC subdevices if a PLC type designation is also entered at the main device. The entry has to be carried out in exactly the same notation as in the hardware catalog of the manufacturer.

The PLC subdevice x: Device description: Index in file property has to be managed for PLC subdevices if these are expected and are identified via a device description file and the associated index. The device description file is specified at the PLC box (main device). The indexes of the device description files additionally have the specification of a preceding context in the AML file (for example M/1000). For a PLC subdevice this context must always be specified during the configuration:

D/ (Device)
R/ (Rack)
DAP/ (Device Access Point)
M/ (Module)