Project Module > Project parameters (detailed description) > Item designations 3 tab

Figure 405: Composition of item designations for terminals and connectors

The Terminals and connectors device type is quite different from conventional devices. Among the differences are the fact that the terminal number is a part of the item designation for terminals, while connection point numbers for conventional devices are not.

Another important difference, is that the composition of item designations for terminals and connectors is separated from conventional devices, PLC and Cables. This means that a terminal help symbol can never interact with for example a conventional main symbol. Terminal help symbols only interact with terminal main symbols. Even if the item designations would be identical, symbols for different device types of can never interact with each other.

In the Terminals and connectors section, you specify how the item designations for these devices are assembled.

The following parts are available for the composition of terminals and connectors:

•Plant

•Location

•Circuit

•Function

•Terminal group

•Terminal number

A complete description of those parts are found in a table below.

How you edit the composition is described in the Editing compositions for item designations topic.

In the lower part of the Terminals and connectors section, you find a check-box named Synchronise separator character with conventional devices. Please refer to the separate sub-topic for a description of that.

In the table below, you will find explanations for all available parts in the composition of item designations for terminals and connectors.

Part	Description
Plant	The Plant part is used for the "function aspect" according to IEC1346, and "function oriented high level designation" according to IEC750. Plant/function is a way of dividing the design according to function, regardless of the location of individual components. Function (plant) is specified in the upper left corner of the drawing frame according to IEC1082, or in the title field according to older standards, in a boundary box, in the plant attribute (ANLAGEI), or as part of the content of the terminal group name attribute (BEZ).
Location	The Location part is used for the "location aspect" according to IEC1346, and "physical location" according to IEC750. Locations is a way of dividing the design according to location, regardless of the function of individual components. Location is specified in the upper left corner of the drawing frame according to IEC1082, or in the title field according to older standards, in a boundary box, in the location attribute (ORT), or as part of the content of the terminal group attribute (BEZ).
Circuit	The Circuit part has two typical uses: •The "circuit" aspect in its instrument context. •The high level "product" aspect according to IEC1346. Product is a way of dividing the design according to how a system is implemented and assembled. "The (product) structure shows the partitioning of a system into single objects with regard to the product aspect independently of where the product is located and which function it fulfils" (IEC81346-12) Circuit/product may be specified in the upper left corner of the drawing frame according to IEC1082, in a boundary box, in the circuit attribute (CIRCUIT), or as part of the content of the terminal group attribute (BEZ). The circuit/product aspect in cadett ELSA is equivalent with plant/function and location in that it may have levels in exactly the same way.
Function	The Function must not be confused with the function aspect (plant), which is something else. Function was originally used in item designation standards older than IEC1346 and IEC750. It was used for a "letter as a characteristic of an individual functional group". However, the original use hardly matters any longer. What does matter, is that over the years, the function has been widely utilised for a number of other purposes, as for instance an additional character after the counting number in item designations for conventional devices, if such is desired, for example to allow multiple item designations with the same counting number. Function may be specified in a boundary box, in the FUNKTION attribute, or as part of the content of the terminal group attribute (BEZ). This function is often used for special purposes, such as special requirements for internal company standards. Please note that Function can not be specified in multiple levels, like plant, location and circuit.
Terminal group	Terminal group refers to the complete item designation of terminals with plant, location, circuit, function and terminal number omitted. The complete item designation of a terminal with terminal number omitted is generally referred to as the "terminal group name". The "terminal group" part of the composition of terminal item designations, refers to the short form of the terminal group name, meaning where plant, location and other parts that can be defined by the surroundings are left out. A typical example is a terminal with complete item designation =A1+S1-X1:1. The complete terminal group name is then =A1+S1-X1. The short form of the terminal group name is -X1. The "terminal group" part of the item designation composition refers to that, to -X1 in the example. The terminal group is specified in the terminal group attribute (BEZ), where it can be specified with or without plant, location and circuit.
Terminal number	The Terminal number is the number of a particular terminal within a terminal group, or the number of a single pin/socket in a connector. The terminal number can contain both digits and letters. Example: In a terminal with complete item designation =A1+S1-X1:1, the terminal number is :1 or 1 depending on how you want to see it. (A typical German interpretation is that the terminal number is ":1". A typical Scandinavian interpretation is that the terminal number is "1"). The terminal number is normally specified in the terminal number attribute (BEZ1), but it can also be specified as part of the content of the terminal group name attribute (BEZ).