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When using manual wire-numbering, it is important that you do this in a correct manner. If the wire-numbering contains errors, those must be corrected before you can produce any meaningful wire-lists. Otherwise, you will end up with infallible flaws in the wire list, for obvious reasons.
There are several requirements, basic rules, which must be obeyed for the wire-numbering to be correct. These are described in the following.
In connection with wire-numbering, the terms “electrical node”, and especially the variation “sub-node”, are often used. These terms are specific for cadett ELSA and somewhat unusual among other electronics and electric technology.
In principle, an electrical node is several connections that are directly connected with each other so that they are on the same electrical potential. A sub-node is the same, but terminals and sockets are from a sub-node perspective treated as breaks.
Within a sub-node, all involved connection points are connected in a chain. They are so to say “sewn” together, one after the other. First, the chain begins with an outgoing wire from the first connection point. This wire ends in connection point number 2 in the chain, where it therefore constitutes the ingoing wire. From there, the wire-chain continues with a new wire to connection point number 3, and so forth until all the connection points in the node have been connected.
There are never more than two wires connected to each connection point, one ingoing and one outgoing.
There is an exception from this, namely terminals. To a terminal, it is possible to connect more than two wires. Besides, they are also separated by an internal and an external side. That is, however, a chapter of its own.
Please note that what is said above still primarily refers to the physical reality, not to the circuit diagram. Two physical wires do not need to be drawn as two lines, because they can be represented with one single line in a circuit diagram.
Each wire (electrical connection, conductor) has a unique wire-number.
This means that a connection point of a symbol, can have no wires connected, one wire connected, or two wires connected. In a circuit diagram this is always drawn as one single line, but that line can represent up to two wires.
Below, the simple basic rules which define a correctly wire-numbered sub-node are stated:
1.Connection points which are not connected to anything, should not have any wire-number symbols.
2.In the beginning of a wire-chain, there must be a connection point with one outgoing wire-number only.
3.In the end of a wire-chain, there must be a connection point with one ingoing wire-number only.
4.In all other connection points of a wire-chain, there must be both an ingoing and an outgoing wire-number, where the ingoing and outgoing wire-numbers must differ.
5.Each outgoing wire-number must have a corresponding ingoing wire-number in the chain.
6.There must never be two or more identical ingoing wire-numbers or two or more identical outgoing wire-numbers in the same chain. Expressed differently, it is forbidden to have several wires with the same wire-number in the same wire-chain.
The lines that you draw in the circuit diagram to define which symbols are connected to each other are only there to define the electrical connection. They have nothing to do with the wiring sequence. They should not have that either, since a circuit diagram primarily defines the function of a design, not the physical realisation of it. The wiring sequence is completely controlled by wire-numbers.
Here can, however, be noted that other document types can be used, such as connection diagrams, where the connection sequence is shown graphically. Such a document can be seen as a graphical wire list and should not be confused with a circuit diagram, which is a function describing document.