Black boxes are used for the grouping of components (connection points, functions or devices), where the allocation of a component to a device can occur in various ways:
- Through the graphical position within the box
- Through the acquisition of the device tag on the box
- Through the "acquisition from the left (or above)" of a component with a DT that is located there.
Elements that are outside the box and / or for which the associated device has not been entered, and / or for which no "transfer from the left (or above)" is possible, are components without device tags.
Example:A lamp without its own DT in the box becomes a lamp without a DT when it is pulled out of the box.
A lamp -H1, when inserted into the box -U1, automatically becomes the nested lamp -U1-H1 and does not become connection points of the box -U1.
A lamp in box -U1, called -H2, would be cross-referenced with the lamp -U1-H2 outside the box (assuming that nesting is enabled).
If you have not entered a device tag, then EPLAN uses the DT from the symbol lying to the left (or above, depending on the plot frame orientation) whose insertion point lies at the same height. This means: If a symbol lies within the box, then it receives the DT of the box; devices that are left (or above) outside the box are not taken into account.
Note:
If the scale is changed on schematic pages, the property texts for the black boxes are visually modified (scaled) in exactly the same way as for other components.
However, a change in the scale does not affect the property texts of the boxes on pages of the type "Panel layout": The corresponding texts remain optically unchanged.
See also