<< Click to Display Table of Contents >> Navigation:  Dynamic OnLine I > The lists > Cable list > Calculation of a cable core list > Which direction does a cable core have?

The previous section discussed which cores each cable are considered having. When this has been defined, a direction must also be given to them. In the cable core list, each cable core is shown in a row of its own. The starting point of the cable core is shown to the left and the ending point to the right (“from” and “to”).

 

It might seem a bit strange that a cable has a direction. In a pure electrical regard, that is of course hardly the case. But, if you think about what would happen if the cable cores were shown in arbitrary directions, one by one, you will probably realise that a consistent direction is very important, both when connecting the cable and when later maintaining it, as well as when searching for errors. All cable cores of a cable must be presented with “the same” direction. To accomplish that, an unambiguous definition of the direction is necessary.

 

The four points below defines how cadett ELSA does precisely that.

 

•The first assumption is that all cores in a cable have the same direction as the first core. Since each cable core is detected separately in the circuit diagram, all cable cores need to be synchronised with the first one, meaning to be turned in the same direction as the first one happens to have. To accomplish this, each cable core is investigated and when needed, turned around. To find out whether a cable core needs to be turned around or not, the connection points from which the cable cores come are first compared. Secondly, the other side is compared, the side to which the cable is connected. The comparison is done on plant, location, and complete item designation for devices, terminal group name for terminals and connector name for connectors. The cores are therefore kept together primarily on the “from side”, and secondarily on the “to side”. When needed, the two connections point of a cable core are switched, to get the same direction as earlier cores in the same cable.

 

•Then two questions remain, namely which direction the first core should have, and what will happen if a cable core has nothing at all in common with the previous core, neither on the "from side", nor on the "to side". (This means that plant, location, and complete item designation are all different on both sides of the cable). The answer is the same in both cases, namely that the graphical appearance in the circuit diagram will decide. The position of the connection point on the “from side” is compared to the position of the connection point on the “to side”. This is done in such a manner that a lower sheet number is considered to come earlier, and that the direction within a drawing sheet is defined as from the top and down, and from the left to the right.

 

•The picky one then wonders, of course, what happens if the cable core goes obliquely down to the left, meaning that it goes forward in the vertical direction but backwards in the horizontal. The answer is that the biggest distance wins.

 

•Of course, the almost pathologically detail-oriented is not content with that but wonders what happens if the distances are equal, meaning if the direction in the circuit diagram is exactly 225 degrees, calculated from connection point to connection point. The answer is that the vertical direction wins.